Dame Agatha Mary Clarissa Christie, Lady Mallowan, DBE (née Miller; 15 September 1890– 12 January 1976) was an English writer. She is known for her 66 detective novels and 14 short story collections, particularly those revolving around her fictional detectives Hercule Poirot and Miss Marple. Christie also wrote the world's longest-running play, a murder mystery, The Mousetrap,[2] and, under the pen name Mary Westmacott, six romances. In 1971 she was appointed a Dame Commander of the Order of the British Empire (DBE) for her contribution to literature.[3]
Christie was born into a wealthy upper-middle-class family in Torquay, Devon. Before marrying and starting a family in London, she had served in a Devon hospital during the First World War, tending to troops coming back from the trenches. She was initially an unsuccessful writer with six consecutive rejections,[4] but this changed when The Mysterious Affair at Styles, featuring Hercule Poirot, was published in 1920.[5] During the Second World War, she worked as a pharmacy assistant at University College Hospital, London, acquiring a good knowledge of poisons which feature in many of her novels.
Guinness World Records lists Christie as the best-selling novelist of all time. Her novels have sold roughly 2 billion copies, and her estate claims that her works come third in the rankings of the world's most-widely published books,[6] behind only Shakespeare's works and the Bible. According to Index Translationum, she remains the most-translated individual author, having been translated into at least 103 languages.[7] And Then There Were None is Christie's best-selling novel, with 100 million sales to date, making it the world's best-selling mystery ever, and one of the best-selling books of all time.[8] Christie's stage play The Mousetrap holds the world record for longest initial run. It opened at the Ambassadors Theatre in the West End on 25 November 1952, and as of September 2018 is still running after more than 27,000 performances.[9][10]
In 1955, Christie was the first recipient of the Mystery Writers of America's highest honour, the Grand Master Award. Later the same year, Witness for the Prosecution received an Edgar Award by the MWA for Best Play.[11]
In 2013, The Murder of Roger Ackroyd was voted the best crime novel ever by 600 fellow writers of the Crime Writers' Association.[12] On 15 September 2015, coinciding with her 125th birthday, And Then There Were None was named the "World's Favourite Christie" in a vote sponsored by the author's estate.[13] Most of her books and short stories have been adapted for television, radio, video games and comics, and more than thirty feature films have been based on her work.
Life and career
Childhood and adolescence: 1890–1910
Agatha Mary Clarissa Miller was born on 15 September 1890 into a wealthy upper-middle-class family in Torquay, Devon.[14]:1 She was the youngest of three children born to Frederick Alvah Miller, an affluent American stockbroker, and his British-born wife Clara Miller née Boehmer.[14]:2–4
Agatha's mother Clara had been born in Belfast in 1854 to Captain Frederick Boehmer and Mary Ann West as the couple's only daughter. Boehmer was killed in a riding accident while stationed on Jersey in April 1863, leaving his widow to raise the children alone on a meagre income. In that same year, 1863, Mary Ann's sister Margaret married a wealthy American, Nathaniel Frary Miller, and the couple settled in Southbourne, West Sussex. Their marriage was childless, but Nathaniel had a son, Frederick, from a previous marriage. Frederick had been sent to Switzerland for his education. Since Mary Ann was virtually penniless and her sister Margaret was wealthy but childless, they arranged that Clara should be raised by her aunt and uncle. It was at the Miller's residence that Clara met Frederick, her aunt's step-son. She and Frederick soon developed a romantic relationship and were married in April 1878.[14]:4–5[14]:2–4
The couple's first child, Margaret Frary Miller (1879–1950), was born in Torquay, where the couple were renting lodgings. Their second child, Louis Montant (1880–1929), was born in the U.S. state of New York, while Frederick was on a business trip. When Frederick's father Nathaniel died, he left his daughter-in-law Clara £2000; she used this money to purchase a villa in Torquay named "Ashfield" in which to raise her family. It was here that her third and final child, Agatha, was born.[14]:6–7

Christie described her childhood as "very happy".[15]:3 She was surrounded by a series of strong and independent women from an early age.[14]:14 Her time was spent alternating between her home in Devon, her step-grandmother and aunt's house in Ealing, West London, and parts of Southern Europe, where her family would holiday during the winter.[14]:15, 24
Agatha was raised in a household with various esoteric beliefs and, like her siblings, believed that her mother Clara was a psychic with the ability of second sight.[14]:13 Agatha's sister Margaret had been sent to Roedean in Sussex for her education, but their mother insisted that Agatha receive a home education. As a result, her parents were responsible for teaching her to read and write and to master basic arithmetic, a subject she particularly enjoyed. They also taught her music, and she learned to play both the piano and the mandolin.[14]:20–21 According to biographer Laura Thomson, Clara believed that Agatha should not learn to read until she was eight. However, thanks to her own curiosity, Agatha taught herself to read much earlier.[16] One of the earliest known photographs of Christie depicts her as a little girl with her first dog, whom she called George Washington.[17]
Christie was a voracious reader from an early age. Among her earliest memories were those of reading the children's books written by Mrs Molesworth, including The Adventures of Herr Baby (1881), Christmas Tree Land (1897), and The Magic Nuts (1898). She also read the work of Edith Nesbit, including The Story of the Treasure Seekers (1899), The Phoenix and the Carpet (1903), and The Railway Children (1906). When a little older, she moved on to reading the surreal verse of Edward Lear and Lewis Carroll.[14]:18–19 In April 1901, at age 10, she wrote her first poem, "The cowslip".[17]
She spent much of her childhood apart from other children, although she devoted much time to her pets. She eventually made friends with a group of other girls in Torquay, noting that "one of the highlights of my existence" was her appearance with them in a youth production of Gilbert and Sullivan's The Yeomen of the Guard, in which she played the hero, Colonel Fairfax.[14]:23–27 This was her last operatic role for, as she later wrote, "an experience that you really enjoyed should never be repeated".[18]:125
Her father was often ill, suffering from a series of heart attacks. His death in November 1901, aged 55, left the family in an uncertain economic situation. Clara and Agatha continued to live together in their Torquay home, Madge had moved to Abney Hall in Cheadle, Cheshire, with her new husband, and Monty had joined the army and been sent to South Africa to fight in the Boer War. Agatha later claimed that her father's death, occurring when she was 11 years old, marked the end of her childhood.[14]:32–34 In 1902, she was sent to receive a formal education at Miss Guyer's Girls School in Torquay but found it difficult to adjust to the disciplined atmosphere. In 1905, she was sent to Paris where she was educated in three pensions– Mademoiselle Cabernet's, Les Marroniers, and then Miss Dryden's– the last of which served primarily as a finishing school.[14]:22–23, 37
Early literary attempts and the First World War: 1910–19
Christie returned to England in 1910 to find that her mother Clara was ill. They decided to spend time together in the warmer climate of Cairo, then a regular tourist destination for wealthy Britons; they stayed for three months at the Gezirah Palace Hotel. Christie attended many social functions in search of a husband. She visited ancient Egyptian monuments such as the Great Pyramid of Giza, but did not exhibit the great interest in archaeology and Egyptology that became prominent in her later years.,[14]:40–41
Returning to Britain, she continued her social activities, writing and performing in amateur theatricals. She also helped put on a play called The BlueBeard of Unhappiness with female friends. Her writing extended to both poetry and music. Some early works saw publication, but she decided against focusing on writing or music as future professions.[14]:45–46
Christie wrote her first short story, The House of Beauty (an early version of her later-published story The House of Dreams,[19]) while recovering in bed from an undisclosed illness. This was about 6,000 words on the topic of "madness and dreams", a subject of fascination for her. Biographer Janet Morgan commented that, despite "infelicities of style", the story was nevertheless "compelling".[14]:48–49
Other stories followed, most of them illustrating her interest in spiritualism and the paranormal. These included "The Call of Wings" and "The Little Lonely God". Magazines rejected all her early submissions, made under pseudonyms, although some were revised and published later, often with new titles.[14]:49–50
Christie then set her first novel, Snow Upon the Desert, in Cairo and drew from her recent experiences in that city, writing under the pseudonym Monosyllaba. She was perturbed when the various publishers she contacted all declined.[14]:50–51 Clara suggested that her daughter ask for advice from a family friend and neighbour, the writer Eden Philpotts, who obliged her enquiry, encouraged her writing, and sent her an introduction to his own literary agent, Hughes Massie, who rejected Snow Upon the Desert and suggested a second novel.[14]:51–52 She continued searching for a husband, and entered into short-lived relationships with four separate men and an engagement with another. She then met Archibald Christie (1889–1962)[20] at a dance given by Lord and Lady Clifford at Ugbrooke, about 12 miles (19 kilometres) from Torquay. Archie was born in India, the son of a barrister in the Indian Civil Service. He was an army officer who was seconded to the Royal Flying Corps in April 1913. The couple quickly fell in love. Upon learning that he would be stationed in Farnborough, Archie proposed marriage, and Agatha accepted.[14]:54–63
With the outbreak of World War I in August 1914, Archie was sent to France to fight the German forces. They married on the afternoon of Christmas Eve 1914 at Emmanuel Church, Clifton, Bristol, which was close to the home of his parents, while Archie was on home leave.[21] Rising through the ranks, he was eventually stationed back to Britain in September 1918 as a colonel in the Air Ministry. Agatha involved herself in the war effort. After joining the Voluntary Aid Detachment in 1914, she attended to wounded soldiers at a hospital in Torquay as an unpaid nurse.[22] Responsible for aiding the doctors and maintaining morale, she performed 3,400 hours of unpaid work between October 1914 and December 1916. On qualifying as an "apothecaries' assistant" in 1917 and working as a dispenser, she earned £16 a year until the end of her service in September 1918. After the war, Agatha and Archie Christie settled in a flat at 5 Northwick Terrace in St. John's Wood, northwest London.[14]:64–74
First novels and Poirot: 1919–23
Christie had long been a fan of detective novels, having enjoyed  Wilkie Collins's The Woman in White and The Moonstone, as well as Sir Arthur Conan Doyle's early Sherlock Holmes stories. She wrote her own detective novel, The Mysterious Affair at Styles, featuring Hercule Poirot, a former Belgian police officer noted for his twirly large "magnificent moustaches" and egg-shaped head. Poirot had taken refuge in Britain after Germany invaded Belgium. Christie's inspiration for the character stemmed from real Belgian refugees who were living in Torquay and the Belgian soldiers whom she helped to treat as a volunteer nurse in Torquay during the First World War.[14]:75–79 She began working on The Mysterious Affair at Styles in 1916, writing most of it on Dartmoor.[17] Her original manuscript was rejected by such publishing companies as Hodder and Stoughton and Methuen. After keeping the submission for several months, John Lane at The Bodley Head offered to accept it, provided that Christie change the ending. She did so, and signed a contract which she later felt was exploitative.[14]:79, 81–82 It was finally published in 1920.[17]
Christie, meanwhile, settled into married life, giving birth to her only child, Rosalind Margaret Hicks, in August 1919 at Ashfield, where the couple spent much of their time, having few friends in London.[14]:79 Archie left the Air Force at the end of the war and started working in the City financial sector at a relatively low salary, though they still employed a maid.[14]:80–81 Her second novel, The Secret Adversary (1922), featured a new detective couple Tommy and Tuppence, again published by The Bodley Head. It earned her £50. A third novel again featured Poirot, Murder on the Links (1923), as did short stories commissioned by Bruce Ingram, editor of The Sketch magazine.[14]:83 In order to tour the world promoting the British Empire Exhibition, the couple left their daughter Rosalind with Agatha's mother and sister. They travelled to South Africa, Australia, New Zealand, and Hawaii.[14]:86–103 [23] They learned to surf prone in South Africa; then, in Waikiki, they were among the first Britons to surf standing up.[24]
Disappearance

In late 1926, Archie asked Agatha for a divorce. He had fallen in love with Nancy Neele, who had been a friend of Major Belcher, director of the British Empire Mission, on the promotional tour a few years earlier. On 3 December 1926, the Christies quarrelled, and Archie left their house, which they named Styles,[25] in Sunningdale, Berkshire, to spend the weekend with his mistress in Godalming, Surrey. That same evening, around 9:45 pm, Christie disappeared from her home, leaving behind a letter for her secretary saying that she was going to Yorkshire. Her car, a Morris Cowley, was later found at Newlands Corner, perched above a chalk quarry, with an expired driving licence and clothes.[26][25]
Her disappearance caused an outcry from the public. The Home Secretary, William Joynson-Hicks, pressured police, and a newspaper offered a £100 reward. Over a thousand police officers, 15,000 volunteers, and several aeroplanes scoured the rural landscape. Sir Arthur Conan Doyle even gave a spirit medium one of Christie's gloves to find the missing woman. Dorothy L. Sayers visited the house in Surrey, later using the scenario in her book Unnatural Death.[27] Christie's disappearance was featured on the front page of The New York Times. Despite the extensive manhunt, she was not found for 10 days.[27][28][29][30] On 14 December 1926, she was found at the Swan Hydropathic Hotel (now the Old Swan Hotel[lower-alpha 1]) in Harrogate, Yorkshire, registered as Mrs Teresa Neele (the surname of her husband's lover) from Cape Town.
Christie's autobiography makes no reference to her disappearance.[18][27] Two doctors diagnosed her as suffering from amnesia (see fugue state), yet opinion remains divided as to why she disappeared. Her biographer Laura Thompson suggested that Christie let this out in the six novels that she wrote between 1930 and 1956 under the nom de plume Mary Westmacott, in a style quite different from her regular detective stories.[17] She was known to be in a depressed state from literary overwork, her mother's death earlier that year, and her husband's infidelity. Public reaction at the time was largely negative, supposing a publicity stunt or an attempt to frame her husband for murder.[32][lower-alpha 2]
The 1979 Michael Apted film Agatha features a disclaimer in the opening credits stating that what follows is an imaginary solution to an authentic mystery. The film starred Vanessa Redgrave and Timothy Dalton as Agatha and Archie, and depicts Christie planning suicide in such a way as to frame her husband's mistress for her "murder". An American reporter, played by Dustin Hoffman, follows her closely and stops the plan. Christie's heirs unsuccessfully sued to prevent the film's distribution.[33] The author Jared Cade interviewed numerous witnesses and relatives for his sympathetic biography Agatha Christie and the Eleven Missing Days, revised in 2011.[34] He provided substantial evidence to suggest that she planned the event to embarrass her husband, never anticipating the resulting escalated melodrama.[35]
The Christies divorced in 1928, and Archie married Nancy Neele. Agatha retained custody of their daughter Rosalind and the Christie name for her writing. During their marriage, she published six novels, a collection of short stories, and a number of short stories in magazines.[36]
Second marriage and later life

In 1928, Christie left England for Istanbul and subsequently for Baghdad on the Orient Express.  Late in this trip, in 1930, she met a young archaeologist 13 years her junior,[37] Max Mallowan, whom she married in September 1930. Their marriage was happy and lasted until Christie's death in 1976.[38] In a 1977 interview, Mallowan recounted his first meeting with Christie, when he took her and a group of tourists on a tour of his expedition site in Iraq.[39]

Christie frequently used settings that were familiar to her for her stories. She often accompanied Mallowan on his archaeological expeditions, and her travels with him contributed background to several of her novels set in the Middle East.[39] Other novels (such as And Then There Were None) were set in and around Torquay, where she was raised. Christie's 1934 novel Murder on the Orient Express was written in the Pera Palace Hotel in Istanbul, Turkey, the southern terminus of the railway. The hotel maintains Christie's room as a memorial to the author.[40]
The Greenway Estate in Devon, acquired by the couple as a summer residence in 1938, is now in the care of the National Trust. Christie often stayed at Abney Hall, Cheshire, owned by her brother-in-law, James Watts, basing at least two stories there: a short story "The Adventure of the Christmas Pudding" in the story collection of the same name, and the novel After the Funeral. "Abney became Agatha's greatest inspiration for country-house life, with all its servants and grandeur being woven into her plots. The descriptions of the fictional Chimneys, Stoneygates, and other houses in her stories are mostly Abney in various forms."[41]
During the Second World War, Christie worked in the pharmacy at University College Hospital, London, where she acquired a knowledge of poisons that she put to good use in her post-war crime novels. For example, the use of thallium as a poison was suggested to her by UCH Chief Pharmacist Harold Davis (later appointed Chief Pharmacist at the UK Ministry of Health), and in The Pale Horse, published in 1961, she employed it to dispatch a series of victims, the first clue to the murder method coming from the victims' loss of hair. So accurate was her description of thallium poisoning that on at least one occasion it helped solve a case that was baffling doctors.[42][43]

Christie lived in Chelsea, first in Cresswell Place and later in Sheffield Terrace. Both properties are now marked by blue plaques. In 1934, she and Max Mallowan purchased Winterbrook House in Winterbrook, a hamlet adjoining the small market town of Wallingford, then within the bounds of Cholsey and in Berkshire.[44]
This was their main residence for the rest of their lives and the place where Christie did most of her writing. This house, too, bears a blue plaque. Christie led a quiet life despite being known in the town of Wallingford,[1] where she was for many years President of the local amateur dramatic society.[45]

Around 1941–42, the British intelligence agency MI5 investigated Christie after a character called Major Bletchley appeared in her 1941 thriller N or M?, which was about a hunt for a pair of deadly fifth columnists in wartime England.[46] MI5 was afraid that Christie had a spy in Britain's top-secret codebreaking centre, Bletchley Park. The agency's fears were allayed when Christie told her friend, the codebreaker Dilly Knox, "I was stuck there on my way by train from Oxford to London and took revenge by giving the name to one of my least lovable characters."[46]
In honour of her many literary works, she was appointed Commander of the Order of the British Empire (CBE) in the 1956 New Year Honours.[47] The next year, she became the President of the Detection Club.[48] In the 1971 New Year Honours, she was promoted to Dame Commander of the Order of the British Empire (DBE).[49] three years after her husband had been knighted for his archaeological work in 1968.[50] They were one of the few married couples where both partners were honoured in their own right. From 1968, owing to her husband's knighthood, Christie could also be styled Lady Mallowan.
From 1971 to 1974, Christie's health began to fail, although she continued to write. Recently, using experimental tools of textual analysis, Canadian researchers have suggested that Christie may have begun to suffer from Alzheimer's disease or other dementia.[51][52][53][54]
Death

Dame Agatha Christie died on 12 January 1976 at age 85 from natural causes at her home Winterbrook House which was located in Winterbrook, Wallingford, Oxfordshire.[1] At the time of her death Winterbrook was still a part of the parish of Cholsey. She is buried in the nearby churchyard of St Mary's, Cholsey, having chosen the plot for their final resting place with her husband Sir Max some ten years before she died. The simple funeral service was attended by about 20 newspaper and TV reporters, some having travelled from as far away as South America. Thirty wreaths adorned Dame Agatha's grave, including one from the cast of her long-running play The Mousetrap and one sent 'on behalf of the multitude of grateful readers' by the Ulverscroft Large Print Book Publishers.[55]
She was survived by her only child, Rosalind Hicks (1919–2004), and only grandson, Mathew Prichard. Her husband, Max, died in 1978, aged 74, after having remarried in 1977. He was interred next to Agatha Christie.
 Agatha Christie's estate and subsequent ownership of works
Christie had set up a private company, Agatha Christie Limited, to hold the rights to her works, and around 1959 she had transferred her 278-acre home, Greenway Estate, to her daughter Rosalind.[56] In 1968, when Christie was almost 80 years old, she sold a 51% stake in Agatha Christie Limited (and therefore the works it owned) to Booker Books (better known as Booker Author's Division), a subsidiary of the British food and transport conglomerate Booker-McConnell (now Booker Group), the founder of the Booker Prize for literature, which later increased its stake to 64%. Agatha Christie Limited remains the owner of the worldwide rights for over 80 of Christie's novels and short stories, 19 plays, and nearly 40 TV films.[57]
After Christie's death in 1976, her remaining 36% share of the company was inherited by her daughter, Rosalind Hicks, who passionately preserved her mother's works, image, and legacy until her own death 28 years later.[56] The family's share of the company allowed them to appoint 50% of the board and the chairman, and thereby to retain a veto over new treatments, updated versions, and republications of her works.[56][58]
In 1993, Hicks founded the Agatha Christie Society and became its first president.[56] In 2004 her obituary in The Telegraph commented that Hicks had been "determined to remain true to her mother's vision and to protect the integrity of her creations" and disapproved of "merchandising" activities.[56] Upon Hicks's death on 28 October 2004, both the Society and the Greenway Estate passed to Christie's grandson, Mathew Prichard.  After his parents' deaths, Prichard donated Greenway and its contents to the National Trust.[56][59] The Society is now chaired and managed by Agatha Christie's great-grandson James Prichard.[60]
Christie's family and family trusts, including James Prichard, continue to own the remaining 36% stake in Agatha Christie Limited,[57] and remain associated with the company. James Prichard became the company's chairman in October 2015.[61] The development of Christie's work continues apace.[62] Mathew Prichard in his own right holds the copyright to some of his grandmother's later literary works (including The Mousetrap).[63]
In 1998, Booker sold a number of its non-food assets to focus on its core business.[58] As part of that, its shares in Agatha Christie Limited (at the time earning £2.1m annual revenue[58]) were sold for £10m to Chorion,[58] a major international media company whose portfolio of well-known authors' works also included the literary estates of Enid Blyton and Dennis Wheatley. In February 2012, some years after a management buyout, Chorion found itself in financial difficulties, and began to sell off its literary assets on the market.[57] The process included the sale of Chorion's 64% stake in Agatha Christie Limited to Acorn Media U.K.[64] In 2014, RLJ Entertainment Inc. acquired Acorn Media U.K., renamed it Acorn Media Enterprises, and incorporated it as the RLJE UK development arm.[65] RLJ Entertainment Inc. was founded by American entrepreneur Robert L. Johnson.
In 2014, media reports stated that the BBC had acquired exclusive TV rights to Christie's works in the UK (previously associated with ITV) and made plans with Acorn's co-operation to air new productions for the 125th anniversary of Christie's birth in 2015.[66] As part of that deal, the BBC broadcast Partners In Crime[67] and And Then There Were None,[68] both in 2015. Subsequent productions have included The Witness for the Prosecution[69] but plans to televise Ordeal by Innocence at Christmas 2017 were delayed due to controversy surrounding one of the cast members.[70] The three-part adaptation aired in April 2018.[71] A three-part adaptation of The A.B.C. Murders starring John Malkovich and Rupert Grint began filming in June 2018 for later broadcast.[72]
Writings

Works of fiction
Hercule Poirot and Miss Marple

Christie's first book, The Mysterious Affair at Styles, was published in 1920 and introduced the detective Hercule Poirot, who became a long-running character in Christie's works, appearing in 33 novels and 54 short stories.[73]
Miss Jane Marple, introduced in the short-story collection The Thirteen Problems in 1927, was based on Christie's grandmother and her "Ealing cronies".[74] Both Jane and Gran "always expected the worst of everyone and everything, and were, with almost frightening accuracy, usually proved right."[15]:422 Marple appeared in 12 novels and 20 stories.
During the Second World War, Christie wrote two novels, Curtain and Sleeping Murder, intended as the last cases of these two great detectives, Hercule Poirot and Miss Marple. Both books were sealed in a bank vault for over thirty years and were released for publication by Christie only at the end of her life, when she realised that she could not write any more novels. These publications came on the heels of the success of the film version of Murder on the Orient Express in 1974.
Christie became increasingly tired of Poirot, much as Sir Arthur Conan Doyle had grown weary of his character Sherlock Holmes. By the end of the 1930s, Christie wrote in her diary that she was finding Poirot "insufferable", and by the 1960s she felt that he was "an egocentric creep".[75]
However, unlike Conan Doyle, Christie resisted the temptation to kill her detective off while he was still popular. She saw herself as an entertainer whose job was to produce what the public liked, and the public liked Poirot.[76] She did marry off Poirot's companion Captain Hastings in an attempt to trim her cast commitments.[15]:268
In contrast, Christie was fond of Miss Marple. However, the Belgian detective's titles outnumber the Marple titles more than two to one. This is largely because Christie wrote numerous Poirot novels early in her career, while The Murder at the Vicarage remained the sole Marple novel until the 1940s. Christie never wrote a novel or short story featuring both Poirot and Miss Marple. In a recording discovered and released in 2008, Christie revealed the reason for this: "Hercule Poirot, a complete egoist, would not like being taught his business or having suggestions made to him by an elderly spinster lady. Hercule Poirot – a professional sleuth – would not be at home at all in Miss Marple's world.".[74]
Poirot is the only fictional character to date to be given an obituary in The New York Times, following the publication of Curtain. It appeared on the front page of the paper on 6 August 1975.[77]
Following the great success of Curtain, Christie gave permission for the release of Sleeping Murder sometime in 1976 but died in January 1976 before the book could be released. This may explain some of the inconsistencies compared to the rest of the Marple series—for example, Colonel Arthur Bantry, husband of Miss Marple's friend Dolly, is still alive and well in Sleeping Murder although he is noted as having died in books published earlier. It may be that Christie simply did not have time to revise the manuscript before she died.[78]
In 2013, the Christie family gave their "full backing" to the release of a new Poirot story, The Monogram Murders, which was written by British author Sophie Hannah.[79] Hannah later released a second Poirot mystery, Closed Casket, in 2016.[80]
Formula and plot devices

Christie's reputation as "The Queen of Crime" was built upon the large number of classic motifs that she introduced, or for which she provided the most famous example. Christie built these tropes into what is now considered classic mystery structure: a murder is committed, there are multiple suspects who are all concealing secrets, and the detective gradually uncovers these secrets over the course of the story, discovering the most shocking twists towards the end. Culprits in Christie's mysteries have included children, policemen, narrators, already deceased individuals, and sometimes comprise no known suspects (And Then There Were None) or all of the suspects (Murder on the Orient Express).
At the end, in a Christie hallmark, the detective usually gathers the surviving suspects into one room, explains the course of their deductive reasoning, and reveals the guilty party, although there are exceptions in which it is left to the guilty party to explain all (such as And Then There Were None and Endless Night).[81][82]
Christie allows some culprits to escape earthly justice for a variety of reasons, such as the passage of time (retrospective cases), in which the most important characters have already died, or by active prescription. Such cases include The Witness for the Prosecution, Murder on the Orient Express, The Man in the Brown Suit, Elephants Can Remember, and The Unexpected Guest. There are instances in which a killer is not brought to justice in the legal sense but does die as a direct result of their plot, sometimes by their own hand at the direction or with the collusion of the detective (usually Hercule Poirot). This occurs in The Murder of Roger Ackroyd, Death on the Nile, Dumb Witness, Crooked House, The Hollow, The Mirror Crack'd from Side to Side, Cat Among the Pigeons, Peril at End House, Nemesis, Appointment with Death, The Secret Adversary, and Curtain. In the last of these (Curtain), no fewer than three culprits die during the course of the story.
In The A.B.C. Murders, the murderer has killed four innocent people and attempted to frame an unstable man for the crimes. Hercule Poirot, however, prevents this easy way out, ensuring a trial and hanging. In And Then There Were None, the killer's own death is intrinsic to the plot; the red herring is when and how the killer actually died. However, stage, film, and television productions of some of these mysteries were traditionally sanitized with the culprits not evading some form of justice, for a variety of reasons– e.g., censors, plot clarity, and Christie's own changing tastes. (When Christie adapted Witness for the Prosecution into a stage play, she lengthened the ending so that the murderer was also killed; this format was followed in screen versions, including the Billy Wilder film from 1957.) In Death Comes as the End, set in ancient Egypt, the culprit is killed by one of the few surviving characters before he can claim another victim.
In some stories, the question remains unresolved of whether formal justice will ever be delivered, such as Five Little Pigs and Endless Night. According to P. D. James, Christie often, but not always, made the unlikeliest character the guilty party. Savvy readers could sometimes identify the culprit by simply identifying the least likely suspect.[83]
On an edition of Desert Island Discs in 2007, Brian Aldiss claimed that Christie had told him that she wrote her books up to the last chapter, then decided who the most unlikely suspect was, after which she would go back and make the necessary changes to "frame" that person.[84] However, John Curran's Agatha Christie: The Secret Notebooks describes different working methods for every book in Christie's bibliography, contradicting the claim by Aldiss.
Titles
Christie's mature novels, from 1940 onwards, often have titles drawn from literature.
Four are from Shakespeare:
Sad Cypress from a song in Twelfth Night: "Come away, come away, death / And in sad cypress let me be laid".
By the Pricking of My Thumbs from Act 4, Scene 1 of Macbeth: "By the pricking of my thumbs / Something wicked this way comes".
There is a Tide... (later Taken at the Flood) from Brutus' speech in Julius Caesar: "There is a tide in the affairs of men / Which, taken at the flood, leads on to fortune".
Absent in the Spring from Sonnet 98: "From you have I been absent in the spring..."
Three are from the Bible:
Evil Under the Sun from Ecclesiastes 5:13 (and restated in 6:1): "There is a sore evil which I have seen under the sun, namely, riches kept for the owners thereof to their hurt".
The Burden from Jesus' words: "Take my yoke upon you, and learn of me... For my yoke is easy, and my burden is light." (Matthew: 11: 29–30).
The Pale Horse from the Revelation of St John (6:8): "I looked, and there before me was a pale horse! Its rider was named Death ...".
Another six are from other works of literature:
The Mirror Crack'd from Side to Side from Tennyson's "The Lady of Shallot": "Out flew the web, and floated wide/The mirror cracked from side to side/'The curse is come upon me," cried/The Lady of Shalott"
The Moving Finger from verse 51 of Edward FitzGerald's translation of the Rubáiyát of Omar Khayyám: "The Moving Finger writes; and, having writ/Moves on..." This, in turn, refers to the Biblical account of Belshazzar's feast (Daniel, chapter 5), which is the origin of the expression "the writing on the wall".
The Rose and the Yew Tree from Section V of "Little Gidding" from T. S. Eliot's Four Quartets: "The moment of the rose and the moment of the yew-tree/Are of equal duration".
Postern of Fate from the poem "Gates of Damascus" by James Elroy Flecker: "Postern of Fate, the Desert Gate, Disaster's Cavern, Fort of Fear/The Portal of Bagdad am I..."
Endless Night from William Blake's Auguries of Innocence: "Some are born to sweet delight / Some are born to endless night".
N or M? from the Catechism in the Book of Common Prayer which asks, "What is your Christian name? Answer N. or M."[85] The "N. or M." stands for the Latin, "nomen vel nomina", meaning "name or names". It is an accident of typography that "nomina" came to be represented by "m".
In such cases, the original context of the title is usually printed as an epigraph.[86] Similarly, the title of Christie's autobiographical travel book Come, Tell Me How You Live is a quote from verse three of the White Knight's poem, "Haddocks' Eyes" from chapter eight of Through the Looking-Glass by Lewis Carroll,[87] and is a play on the word "tell", an archaeological mound.[88]
The title of The Mousetrap is purportedly an allusion to Shakespeare's play Hamlet, in which "The Mousetrap" is Hamlet's answer to Claudius's inquiry about the name of the play whose prologue and first scene he and his court have just watched (III, ii).[89]
Seven stories are built around words from well known children's nursery rhymes: And Then There Were None (from "Ten Little Indians"), One, Two, Buckle My Shoe (from "One, Two, Buckle My Shoe"), Five Little Pigs (from "This Little Piggy"), Crooked House (from "There Was a Crooked Man"), A Pocket Full of Rye (from "Sing a Song of Sixpence"), Hickory Dickory Dock (from "Hickory Dickory Dock"), and Three Blind Mice (from "Three Blind Mice"). Similarly, the novel Mrs McGinty's Dead is named after a children's game that is explained in the course of the novel.
Character stereotypes
Christie occasionally inserted stereotyped descriptions of characters into her work, particularly before the end of the Second World War (when such attitudes were more commonly expressed publicly), and particularly in regard to Italians, Jews, non-Europeans, and sometimes Americans, the last usually as impossibly naïve or uninformed. For example, she described "Hebraic men with hook-noses wearing rather flamboyant jewellery" in the first editions of the collection The Mysterious Mr Quin (1930), in the short story "The Soul of the Croupier"; in later editions, the passage was edited to describe "sallow men" wearing same.
In The Hollow, published as late as 1946, one of the more unsympathetic characters is "a Whitechapel Jewess with dyed hair and a voice like a corncrake... a small woman with a thick nose, henna red and a disagreeable voice". To contrast with the more stereotyped descriptions, Christie sometimes showed "foreigners" as victims or potential victims at the hands of English malefactors, such as, respectively, Olga Seminoff (Hallowe'en Party) and Katrina Reiger (in the short story "How Does Your Garden Grow?"). Jewish characters are often seen as un-English (such as Oliver Manders in Three Act Tragedy), but they are rarely the culprits.[90]
Often, she is affectionate or teasing with her prejudices. After four years of war-torn London, Christie hoped to return some day to Syria, which she described as "gentle fertile country and its simple people, who know how to laugh and how to enjoy life; who are idle and gay, and who have dignity, good manners, and a great sense of humour, and to whom death is not terrible."[15]:187
She had trouble with an incompetent Swiss French nursery helper (Marcelle) for toddler Rosalind, and as a result she decided, "Scottish preferred... good with the young. The French were hopeless disciplinarians... Germans good and methodical, but it was not German that I really wanted Rosalind to learn. The Irish were gay but made trouble in the house; the English were of all kinds."[15]:327
Non-fiction writings
Christie published relatively few non-fiction works:
Come, Tell Me How You Live, about working on an archaeological dig, drawn from her life with second husband Max Mallowan
The Grand Tour: Around the World with the Queen of Mystery, a collection of correspondence from her 1922 Grand Tour of the British empire, including South Africa, Australia, New Zealand, and Canada
Agatha Christie: An Autobiography, published posthumously in 1977
Critical reception and legacy
Often referred to as the "Queen of Crime" or "Queen of Mystery", Agatha Christie is the world's best-selling mystery writer and is considered a master of suspense, plotting, and characterisation.[91][92][93] Some critics, however, have regarded Christie's plotting as superior to her skill with other literary elements. Novelist Raymond Chandler criticised her in his essay "The Simple Art of Murder", and American literary critic Edmund Wilson was dismissive of Christie and the detective fiction genre generally in his New Yorker essay, "Who Cares Who Killed Roger Ackroyd?"[94]
In honour of the 125th anniversary of her birth, 25 contemporary mystery writers and one publisher revealed their views on Christie's works. Many of the authors read Christie's novels first, before other mystery writers, in English or in their native language, influencing their own writing, and nearly all still view her as the "Queen of Crime", and creator of the plot twists used by mystery authors. Nearly all had one or more favourites among Christie's mysteries, and find her books good to read now, nearly 100 years after her first novel was published. Several of the authors would be very pleased to have their own novels in print in 100 years. Just one of the 25 authors held with Edmund Wilson's views.[95] Harper Collins also published a souvenir magazine Shocking Real Murders: Behind Her Classic Mysteries.[96]
The Guinness Book of World Records lists Christie as the best-selling novelist of all time. Her novels have sold roughly 2 billion copies, and her estate claims that her works come third in the rankings of the world's most-widely published books,[6] behind only Shakespeare's works and the Bible. Half of the sales are of English language editions, and the other half in translation.[97] According to Index Translationum, she remains the most-translated individual author– having been translated into at least 103 languages.[7] And Then There Were None is Christie's best-selling novel, with 100 million sales to date, making it the world's best-selling mystery ever, and one of the best-selling books of all time.[8]
In 2012, Christie was among the British cultural icons selected by artist Sir Peter Blake to appear in a new version of his most famous artwork– the Beatles' Sgt. Pepper's Lonely Hearts Club Band album cover– to celebrate the British cultural figures of his life that he most admires.[98][99]
Interests and influences
Archaeology

The lure of the past came up to grab me. To see a dagger slowly appearing, with its gold glint, through the sand was romantic. The carefulness of lifting pots and objects from the soil filled me with a longing to be an archaeologist myself.
—[14]:389[15]

Christie had a lifelong interest in archaeology. She met her second husband, Sir Max Mallowan, a distinguished archaeologist, on a trip to the excavation site at Ur in 1930. But her fame as an author far surpassed his fame in archaeology.[100] Prior to meeting Mallowan, Christie had not had any extensive brushes with archaeology, but once the two married, they made sure to only go to sites where they could work together. Christie accompanied Mallowan on countless archaeological trips, spending 3–4 months at a time in Syria and Iraq at excavation sites at Ur, Nineveh, Tell Arpachiyah, Chagar Bazar, Tell Brak, and Nimrud. She wrote novels and short stories, but also contributed work to the archaeological sites, more specifically to the archaeological restoration and labelling of ancient exhibits, including tasks such as cleaning and conserving delicate ivory pieces, reconstructing pottery, developing photos from early excavations which later led to taking photographs of the site and its findings, and taking field notes.[101]
Christie would always pay for her own board and lodging and her travel expenses so as to not influence the funding of the archaeological excavations, and she also supported excavations as an anonymous sponsor.[101] During their time in the Middle East, there was also a large amount of time spent travelling to and from Mallowan's sites. Their extensive travelling had a strong influence on her writing, as some type of transportation often plays a part in her murderer's schemes. The large amount of travel was reused in novels such as Murder on the Orient Express, as well as suggesting the idea of archaeology as an adventure itself.[102]
After the Second World War, she chronicled her time in Syria with fondness in Come Tell Me How You Live. Anecdotes, memories, funny episodes are strung in a rough timeline, with more emphasis on eccentric characters and lovely scenery than on factual accuracy.[15]:1985 From 8 November 2001 to 24 March 2002, The British Museum had an exhibit named Agatha Christie and Archaeology: Mystery in Mesopotamia, which presented the life of Agatha Christie and the influences of archaeology in her life and works.[101]
Use of archaeology in her writing
Many of the settings for Christie's books were directly inspired by the many archaeological field seasons spent in the Middle East on the sites managed by her husband Max. The extent of her time spent at the many locations featured in her books is apparent from the extreme detail in which she describes them. One such site featured in her work is the temple site of Abu Simbel, depicted in Death on the Nile. Also there is the great detail in which she describes life at the dig site in Murder in Mesopotamia. Among the characters in her books, Christie has often given prominence to the archaeologists and experts in Middle Eastern cultures and artefacts. Most notable are the characters of Dr. Eric Leidner in Murder in Mesopotamia and Signor Richetti in Death on the Nile, while many minor characters were archaeologists in They Came to Baghdad.
Some of Christie's best known novels with heavy archaeological influences are:
Murder in Mesopotamia (1936)– the most archaeologically influenced of all her novels, as it is set in the Middle East at an archaeological dig site and associated expedition house. The main characters include archaeologist Dr. Eric Leidner, his wife, many specialists and assistants, and the men working on the site. The novel is noted most for its careful description of the dig site and house, which showed that the author had spent much of her time in very similar situations. The characters in this book in particular are also based on archaeologists whom Christie knew from her personal experiences on excavation sites.
Death on the Nile (1937)– takes place on a tour boat on the Nile. Many archaeological sites are visited along the way and one of the main characters, Signor Richetti, is an archaeologist.
Appointment with Death (1938)– set in Jerusalem and its surrounding area. The death itself occurs at an old cave site in Petra and offers some very descriptive details of sites which Christie herself could have visited in order to write the book.
They Came to Baghdad (1951)– inspired by Christie's own trips to Baghdad with Mallowan, and involves an archaeologist as the heroine's love interest.
Portrayals in fiction
Christie has been portrayed on a number of occasions in film and television. Several biographical programmes have been made, such as BBC television's Agatha Christie: A Life in Pictures (2004; in which she was portrayed by Olivia Williams, Anna Massey, and Bonnie Wright, at different stages in her life), and in Season 3, Episode 1 of ITV Perspectives: "The Mystery of Agatha Christie" (2013), hosted by David Suchet, who plays Hercule Poirot on television.[103]
Christie has also been portrayed fictionally. Some of these portrayals have explored and offered accounts of Christie's disappearance in 1926, including the film Agatha (1979) (with Vanessa Redgrave, in which she sneaks away to plan revenge against her husband), and the Doctor Who episode "The Unicorn and the Wasp" (17 May 2008), with Fenella Woolgar, in which her disappearance is the result of her suffering a temporary breakdown owing to a brief psychic link being formed between her and an alien wasp called the Vespiform. Others, such as Hungarian film, Kojak Budapesten (1980; not to be confused with the 1986 comedy by the same name) create their own scenarios involving Christie's criminal skill. In the TV play, Murder by the Book (1986), Christie herself (Dame Peggy Ashcroft) murdered one of her fictional-turned-real characters, Poirot. The heroine of Liar-Soft's visual novel Shikkoku no Sharnoth: What a Beautiful Tomorrow (2008), Mary Clarissa Christie, is based on the real-life Christie. Christie features as a character in Gaylord Larsen's Dorothy and Agatha and The London Blitz Murders by Max Allan Collins.[104][105] A fictionalized account of Christie's disappearance is the central theme of a Korean musical, Agatha.[106] A young Agatha Christie is depicted in the Spanish historical television series Grand Hotel (2011). Aiding the local detectives, Agatha finds inspiration to write her new novel.
See also

Agatha Christie: A Life in Pictures (her life story in a 2004 BBC drama)
Abney Hall (home to her brother-in-law; several books use Abney as their setting)
Greenway Estate (Christie's former home in Devon. The house and grounds are now in the possession of the National Trust and open to the public)
Agatha Christie indult (an oecumenical request to which Christie was signatory seeking permission for the occasional use of the Tridentine (Latin) mass in England and Wales)
Agatha Award
Agatha Christie Award (Japan)
Agatha Christie (video game series)
Notes

Sources

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Library resources about
 Agatha Christie
By Agatha Christie

No URL found. Please specify a URL here or add one to Wikidata.
 on IMDb
 at Project Gutenberg
 at Internet Archive
 at Open Library
 blue plaque at Cholsey
 in The Guardian

, a fan site
 at the Imperial War Museum


Rusts are plant diseases caused by pathogenic fungi of the order Pucciniales (previously also known as Uredinales).
An estimated 168 rust genera and approximately 7,000 species, more than half of which belong to the genus Puccinia, are currently accepted.[1] Rust fungi are highly specialized plant pathogens with several unique features. Taken as a group, rust fungi are diverse and affect many kinds of plants. However, each species has a very narrow range of hosts and cannot be transmitted to non-host plants. In addition, most rust fungi cannot be grown easily in pure culture.
A single species of rust fungi may be able to infect two different plant hosts in different stages of its life cycle, and may produce up to five morphologically and cytologically distinct spore-producing structures viz., spermogonia, aecia, uredinia, telia, and basidia in successive stages of reproduction.[2]  Each spore type is very host specific, and can typically infect only one kind of plant.
Rust fungi are obligate plant pathogens that only infect living plants. Infections begin when a spore lands on the plant surface, germinates, and invades its host. Infection is limited to plant parts such as leaves, petioles, tender shoots, stem, fruits, etc.[1] Plants with severe rust infection may appear stunted, chlorotic (yellowed), or may display signs of infection such as rust fruiting bodies. Rust fungi grow intracellularly, and make spore-producing fruiting bodies within or, more often, on the surfaces of affected plant parts.[1]  Some rust species form perennial systemic infections that may cause plant deformities such as growth retardation, witch's broom, stem canker, galls, or hypertrophy of affected plant parts.
Rusts get their name because they are most commonly observed as deposits of powdery rust-coloured or brown spores on plant surfaces. The Roman agricultural festival Robigalia (April 25) has ancient origins in combating wheat rust.[3]
Impacts
Rusts are considered among the most harmful pathogens to agriculture, horticulture and forestry. Rust fungi are major concerns and limiting factors for successful cultivation of agricultural and forestry crops.  White pine blister rust, wheat stem rust, soybean and coffee rust are examples of notoriously damaging, economically important rusts.[1]
Life cycle
All rusts are obligate parasites, meaning that they require a living host to complete their life cycle. They generally do not kill the host plant but can severely reduce growth and yield.[4] Cereal crops can be devastated in one season and trees that get infected in the main stem within their first five years by the rust Cronartium quercuum often die.[5]

Rusts can produce up to five spore types from corresponding fruiting body types during their life cycle, depending on the species. Roman numerals have traditionally been used to refer to these morphological types.
0-Pycniospores (Spermatia) from Pycnidia. These serve mainly as haploid gametes in heterothallic rusts.
I-Aeciospores from Aecia. These serve mainly as non-repeating, dikaryotic, asexual spores, and go on to infect the primary host.
II-Urediniospores from Uredia (Uredinia). These serve as repeating dikaryotic vegetative spores. These spores are referred to as the repeating stage because they can cause auto-infection on the primary host, re-infecting the same host from which the spores were produced. They are often profuse, red/orange, and a prominent sign of rust disease.
III-Teliospores from Telia. These dikaryotic spores are often the survival/overwintering stage of life cycle. Later they germinate to produce basidia.
IV-Basidiospores from Teliospores. These haploid spores often infect the alternate host in Spring.[6][7] although these are rarely observed outside of the laboratory.
Rust fungi are often categorized by their life cycle. Three basic types of life cycles are recognized based on the number of spore states as macrocyclic, demicyclic, and microcyclic.[1] The macrocyclic life cycle has all spore states, the demicyclic lacks the uredinial state, and the microcyclic cycle lacks the basidial, pycnial, and the aecial states, thus possess only uredinia and telia.  Spermagonia may be absent from each type but especially the microcyclic life cycle.  In macrocyclic and demicyclic life cycles, the rust may be either host alternating (heteroecious), i.e., the aecial state is on one kind of plant but the telial state on a different and unrelated plant, or non-host alternating (autoecious), i.e., the aecial and telial states on the same kind of plant.[1] Heteroecious rust fungi require two unrelated hosts to complete their life cycle, with the primary host being infected by aeciospores and the alternate host being infected with basidiospores. This can be contrasted with an autoecious fungus which can complete its life cycle on a single host species.[6] Understanding the life cycles of rust fungi allows for proper disease management.[8]
Host plant-rust fungus relationship
There are definite patterns of relationship with host plant groups and the rust fungi that parasitize them.  Some genera of rust fungi, especially Puccinia and Uromyces, comprise species that are capable of parasitizing plants of many families.  Other rust genera appear to be restricted to certain plant groups.  Host restriction may, in heteroecious species, apply to both phases of life cycle or to only one phase.[1]
Infection process
The fungi produce asexual spores which disperse by wind, water or by insect vectors[9] spreading the infection.
Rust fungi are biotrophs, taking nutrients from living cells. When airborne spores settle on a plant, weak hydrophobic interactions are formed with the cutin on the plant cell surface, securing it. By a process not fully understood, the production of mucous like substances called 'adhesins', initially stick the spore to the plant surface.[10]

Once attached, the spore germinates by growing a germ tube and eventually locates a stoma by a touch responsive process known as thigmotropism. This involves growing towards a ridge between the epidermal cells, followed by a perpendicular growth which end at the stoma.[11] Inside the stoma, the hyphae tips flatten out to form structures known as appressoria that lock to the cell walls.[12] It is thought that the whole process is mediated by a mechano-sensitive calcium ion channel, located within the germ tube tip, which produces electric currents that stretch the cell membranes, changing gene expression and forming the appresorium.[13]
Then a peg grows into the plant's mesophyll cells. The peg produces specialised hyphal tips, known as haustoria. These spread around the plant cells without invading the membranes. The plant cell membranes invaginate around the main haustorial body forming a space known as the extra-haustorial matrix. An iron and phosphorus rich neck band bridges the plant and fungal membranes in the space between the cells for water flow, known as the apoplast, thus preventing the nutrients reaching the plant's cells. The haustorium contains amino acid and hexose sugar transporters and H+-ATPases which are used for active transport of nutrients from the plant nourishing the fungus.[14] It continues growing until spore growth occurs. The process repeats every 10 – 14 days, producing numerous spores, carried by wind to new hosts.
Common rust fungi in agriculture
[6][8][15]
Cronartium ribicola (White pine blister rust); the primary host are currants, and white pines the secondary. Heterocyclic and macrocyclic
Gymnosporangium juniperi-virginianae (Cedar-apple rust); Juniperus virginiana is the primary (telial) host and apple, pear or hawthorn is the secondary (aecial) host. Heteroecious and demicyclic
Hemileia vastatrix (Coffee rust); Primary host is coffee plant; unknown alternate host. Heteroecious
Phakopsora meibomiae and P. pachyrhizi (Soybean rust); Primary host is soybean and various legumes. Unknown alternate host. Heteroecious
Puccinia coronata (Crown Rust of Oats and Ryegrass); Oats are the primary host; Rhamnus spp. (Buckthorn) is alternate host. Heteroecious and macrocyclic
Puccinia graminis (Stem rust of wheat and Kentucky bluegrass, or black rust of cereals); Primary hosts include: Kentucky bluegrass, barley, and wheat; Common barberry is the alternate host. Heteroecious and macrocyclic
Puccinia hemerocallidis (Daylily rust); Daylily is primary host; Patrina sp is alternate host. Heteroecious and macrocyclic
Puccinia persistens subsp. triticina causes wheat rust in grains. It is also known as 'brown or red rust'.
Puccinia sorghi causes common rust in corn[16]
Puccinia striiformis causes 'Yellow rust' in cereals.
Uromyces appendiculatus causes a rust of beans.
Uromyces phaseoli (Bean rust); Primary host: bean. Autoecious and macrocyclic
Puccinia melanocephala causes 'Brown rust' in sugarcane.
Puccinia kuehnii causes 'Orange rust' in sugarcane.
Management of rust fungi diseases
The control methods of rust fungus diseases depend largely on the life cycle of the particular pathogen. The following are examples of disease management plans used to control macrocyclic and demicyclic diseases:
Macrocyclic Disease: Developing a management plan for this type of disease depends largely on whether the repeating stage (urediniospores) occur on the economically important host plant or the alternate host. For example, the repeating stage in white pine blister rust disease does not occur on white pines but on the alternate host, Ribes spp. During August and September Ribes spp. give rise to teliospores which infect white pines. Removal of the alternate host disrupts the life cycle of the rust fungi Cronartium ribicola, preventing the formation of basidiospores which infect the primary host. Although spores from white pines cannot infect other white pines, survival spores may overwinter on infected pines and reinfect Ribes spp. the following season. Infected tissue is removed from white pines and strict quarantines of Ribes spp. are maintained in high risk areas.[6][17]
Puccinia graminis is a macrocyclic heteroecious fungus that causes wheat stem rust disease. The repeating stage in this fungus occurs on wheat and not the alternate host, barberry. The repeating stage allows the disease to persist in wheat even though the alternate host may be removed. Planting resistant crops is the ideal form of disease prevention, however, mutations can give rise to new strains of fungi that can overcome plant resistance. Although the disease cannot be stopped by removal of the alternate host, the life cycle is disrupted and the rate of mutation is decreased because of reduced genetic recombination. This allows resistance bred crops to remain effective for a longer period of time.[6][18]
Demicyclic Disease: Because there is no repeating stage in the life cycle of demicyclic fungi, removal of the primary or the alternate host will disrupt the disease cycle. This method, however, is not highly effective in managing all demicyclic diseases. Cedar-apple rust disease, for example, can persist despite removal of one of the hosts since spores can be disseminated from long distances. The severity of Cedar-apple rust disease can be managed by removal of basidiospore producing galls from junipers or the application of protective fungicides to junipers.[19]
Home control
Rust is very hard to treat. Fungicides such as Mancozeb or Triforine may help but may never eradicate the disease. Some organic preventative solutions are available and sulphur powder is known to stop germination. High standards of hygiene and good soil drainage and careful watering may minimise problems. Any appearance of rust must be immediately dealt with by removing and burning all affected leaves. Composting, or leaving infected vegetation on the ground will spread the disease.
Commercial control
In large plantations in USA, fungicides are applied by air. The process is expensive and fungicide application is best reserved for seasons when foliar diseases are severe. Research indicates, the higher the foliar disease severity, the greater the return from the use of fungicides.[20] There are a variety of preventative methods that can also be employed.
Symptoms of rust disease are correlated to relatively high moisture. The avoidance of overhead watering at night, using drip irrigation, reducing crop density, and using fans to circulate air flow will lower the relative moisture and decrease the severity of rust infection.
The use of rust resistant plants
Crop rotation can break the disease cycle because many rusts are host specific.
Inspect all imported plants and cuttings for symptoms. It is important to continuously observe these plants because rust diseases have a latent period (plant has the disease but shows no symptoms).
Many crops, such as wheat, are replanted with disease-free seed.[4][18]
Host plants affected
Rusts are often named after the host species that they infect. For example; Puccinia xanthii infects the flowering plant cocklebur (Xanthium). It is probable that most plant species are affected by some species of rust. Recently, a total of 95 rust fungi belonging to 25 genera associated with 117 forest plant species belonging to 80 host genera under 43 host families were reported from the Western Ghats, Kerala, India.[1] Rust fungi include:

Aecidium
Cerotelium
Chaconia
Coleosporium
Crossopsora
Didymopsorella
Hamspora
Hapalophragmidium
Hemileia
Kernkampella
Kuehneola
Kweilingia
Macabuna
Maravalia
Melampsora
Olivea
Physopella
Puccinia
Ravenelia
Uraecium
Uredo
Uredopeltis
Uromyces
Xenostele
Zaghouania

Rust infected host genera include:[1]

Acacia
Acalypha
Ageratina
Albizia
Arundinaria
Bambusa
Bidens
Blepharis
Bombax
Bridelia
Callicarpa
Canarium
Canthium
Catunaragam
Cinnamomum
Cissus
Cleistanthus
Clerodendron
Coffea
Coix
Cosmostigma
Crotalaria
Dalbergia
Dendrocalamus
Derris
Diospyros
Dipterocanthus
Elaeagnus
Elephantopus
Elettaria
Eragrostis
Euphorbia
Ficus
Flacourtia
Grewia
Holarrhena
Holoptelia
Hypericum
Ichnocarpus
Ischaemum
Jasminum
Justicia
Loesneriella
Luvunga
Meiogyne
Meliosma
Mimusops
Morus
Neolitzea
Ocimum
Olea
Oxalis
Pavetta
Persicaria
Phyllanthus
Plectranthus
Plumeria
Pongamia
Premna
Protasparagus
Rubus
Salix
Spondia
Strobilanthes
Strychnos
Tabernaemontana
Terminalia
Toddalia
Trichosanthes
Vernonia
Vigna
Wrightia
Xanthophyllum
Xylia
Ziziphus

Some of the better known hosts include:

Arisaema triphyllum, Jack-in-the-pulpit
Avena sativa, Oats
Berberis vulgaris, Common barberry
Vicia faba - Broad beans
Coffea arabica - Coffee
Crataegus monogyna - Hawthorn
Chrysanthemum
Cydonia - Quince
Euphorbia maculata, Spotted Spurge
Fuchsia spp,
Garlic
Hordeum vulgare, Barley
Juniperus virginiana, Red Cedar (Juniper apple disease)

Juniperus communis - Juniper
Allium ampeloprasum - Leek
Malus – Apple
Mentha piperita - Peppermint
Mespilus - Medlar
Onion
Pelargonium
Primula veris
Primula vulgaris
Pyrus - Pear
Rosa spp, Roses
Triticum spp., Wheat
Oxalis spp., Oxalis
Secale cereale, Rye
Senecio vulgaris -Common groundsel
Xanthium canadense Cocklebur

Hyperparasites of rusts
In the family Sphaeropsidaceae of Sphaeropsidales fungi, species of the genus Darluca are hyperparasites on rusts.[21]
See also

Stem rust
Wheat leaf rust
Leaf rust (barley)
Fungus
Smut (fungus)
Soybean rust
Rust (programming language) - named after the Rust fungus
Gallery

Rust fungus on a leaf, under low magnification.
Urediniospores of a rust fungus.
 Diagram representing the infection process of rust fungi
Rust fungus, Puccinia urticata on the surface of a nettle leaf

[1]


Information Technology in India is an industry consisting of two major components: IT services and business process outsourcing (BPO).[1] The sector has increased its contribution to India's GDP from 1.2% in 1998 to 7.7% in 2017.[2] According to NASSCOM, the sector aggregated revenues of US$160 billion in 2017,[3][4] with export revenue standing at US$99 billion and domestic revenue at US$48 billion, growing by over 13%. The United States accounts for two-thirds of India's IT services exports.[5]
History

India's IT Services industry was born in Mumbai in 1967 with the establishment of the Tata Group in partnership with Burroughs.[6] The first software export zone, SEEPZ – the precursor to the modern-day IT park – was established in Mumbai in 1973. More than 80 percent of the country's software exports were from SEEPZ in the 1980s.[7]
The Indian economy underwent major economic reforms in 1991, leading to a new era of globalization and international economic integration, and annual economic growth of over 6% from 1993–2002.  The new administration under Sri Atal Bihari Vajpayee (Posthumus) (who was Prime Minister from 1998–2004) placed the development of Information Technology among its top five priorities and formed the Indian National Task Force on Information Technology and Software Development.
Wolcott & Goodman (2003) report on the role of the Indian National Task Force on Information Technology and Software Development:
Within 90 days of its establishment, the Task Force produced an extensive background report on the state of technology in India and an IT Action Plan with 108 recommendations. The Task Force could act quickly because it built upon the experience and frustrations of state governments, central government agencies, universities, and the software industry. Much of what it proposed was also consistent with the thinking and recommendanotions of international bodies like the World Trade Organization (WTO), International Telecommunications Union (ITU), and World Bank. In addition, the Task Force incorporated the experiences of Singapore and other nations, which implemented similar programs. It was less a task of invention than of sparking action on a consensus that had already evolved within the networking community and government.

Regulated VSAT links became visible in 1994.[8] Desai (2006) describes the steps taken to relax regulations on linking in 1991:
In 1991 the Department of Electronics broke this impasse, creating a corporation called Software Technology Parks of India (STPI) that, being owned by the government, could provide VSAT communications without breaching its monopoly. STPI set up software technology parks in different cities, each of which provided satellite links to be used by firms; the local link was a wireless radio link. In 1993 the government began to allow individual companies their own dedicated links, which allowed work done in India to be transmitted abroad directly. Indian firms soon convinced their American customers that a satellite link was as reliable as a team of programmers working in the clients’ office.

Videsh Sanchar Nigam Limited (VSNL) introduced Gateway Electronic Mail Service in 1991, the 64 kbit/s leased line service in 1992, and commercial Internet access on a visible scale in 1992. Election results were displayed via National Informatics Centre's NICNET.
"The New Telecommunications Policy, 1999" (NTP 1999) helped further liberalise India's telecommunications sector. The Information Technology Act, 2000 created legal procedures for electronic transactions and e-commerce.
A joint EU-India group of scholars was formed on 23 November 2001 to further promote joint research and development. On 25 June 2002, India and the European Union agreed to bilateral cooperation in the field of science and technology. India holds observer status at CERN, while a joint India-EU Software Education and Development Center will be located in Bangalore.[9]
Contemporary situation
In the contemporary world economy India is the largest exporter of IT. Exports dominate the Indian IT industry and constitute about 79% of the industry's total revenue. However, the domestic market is also significant, with robust revenue growth.[2] The industry’s share of total Indian exports (merchandise plus services) increased from less than 4% in FY1998 to about 25% in FY2012. The technologically-inclined services sector in India accounts for 40% of the country's GDP and 30% of export earnings as of 2006, while employing only 25% of its workforce, according to Sharma (2006).  According to Gartner, the "Top Five Indian IT Services Providers" are Tata Consultancy Services, Infosys, Cognizant, Wipro, and HCL Technologies.[10][11]
Major information technology hubs
Bangalore
Bangalore is known as the Silicon Valley of India.[12][13] Notable tech park are Electronics City Phase I & II, ITPL, Bagmane Tech Park, Embassy Golf Links, Manyata Tech Park, Global Village Tech Park, Embassy TechVillage
Hyderabad
Hyderabad – also known as the HITEC City or Cyberabad – is a major global information technology hub, and the largest bioinformatics hub in India.[14][15] Hyderabad has emerged as the second largest city in the country for software exports pipping competitors Chennai and Pune.[16][17][18] Notable tech and pharma parks are HITEC City, Genome Valley, and Hyderabad Pharma City
Kolkata
Kolkata is also one of the leading Indian and international IT services and outsourcing exporters.
Pune
Pune is one of the leading Indian and international IT services and outsourcing exporters. The next biggest IT park of India (Rajiv Gandhi IT Park at Hinjawadi) is expected to scale up to phase 7.
Chennai
Chennai has a good IT infrastructure with dedicated expressway nicknamed as IT expressways, and many other IT parks promoted by both government agency (Elcot) Electronics Corporation of Tamil Nadu and private entities.
Mumbai and Navi Mumbai
Mumbai and Navi Mumbai have major IT parks.
National Capital Region
The National Capital Region includes Delhi, Gurgaon and Noida.
Employment generation
India's growing stature in the Information Age enabled it to form close ties with both the United States and the European Union. However, the recent global financial crises have deeply impacted Indian IT companies as well as global companies. As a result, hiring has dropped sharply, and employees are looking at different sectors like financial services, telecommunications, and manufacturing, which have been growing phenomenally over the last few years.[19]
With fundamental structural changes visible everywhere in the IT services due to Cloud computing, proliferation of Social media, Big data, Analytics all leading to digital services and digital economy, many of the leading companies in India's IT sector reported lower headcounts in their financial results.[20]
See also
Electronics and semiconductor manufacturing industry in India
Supercomputing in India
List of Indian IT companies
List of public listed software companies of India
PARAM

Sources

Which country in the world has the largest information technology industry?