Genotype and environment effects on sunflower nectar and their relationships to crop pollination
Keywords:floral rewards, plant-pollinator interactions, nectar, pollen, pollinator exclusion, bees
Whether caused by genotype (G) or environment (E), floral trait variation has consequences for plants and their pollinators. Cultivated sunflower is a model system to explore floral trait variation; though sunflowers are bred to self-pollinate, benefits of pollination by bees remain substantial. To better understand sunflower-pollinator interactions, experiments were conducted to: (i) examine genotype and environment effects on nectar quantity and quality under controlled conditions, and (ii) assess effects of bags used for pollinator exclusion on nectar quantity, quality and bee foraging in a field environment. Contrasting temperature treatments (28°C, 21°C, 28°C / 16°C) reveal environment effects or G × E interactions for nectar volume (µl / floret), concentration (°Brix), and sugar composition (% sucrose). Bags used to exclude sunflower pollinators resulted in nectar volumes greater than plants with unrestricted access for bees (= open-pollination), and in ≈ 5-fold increased visitation by wild bees after bags were removed. Differences in bee visits to plants that were previously bagged versus plants never bagged decreased over the 2 h following bag removal. Though genetic variation in sunflower nectar is affected by the environment and G × E interactions, improving pollination via plant breeding still appears feasible. Future research on intraspecific variation in pollen rewards could be helpful, especially because pollen has received little research compared to nectar. For research with nectar or pollen, it seems desirable to measure floral rewards with methods that don’t rely on pollinator exclusion (bags or cages), which should provide more realistic data on what pollinators experience while foraging.
Atlagić J, Joksimović J, Sakac Z, Miklic V, Dusanić N (2003) Mode of inheritance and heritability of disc flower corolla length and nectar content in sunflower. Genetika 35: 59–65. https://doi.org/10.2298/GENSR0301059A
Bailes EJ, Patrick JG, Glover BJ (2018) An analysis of the energetic reward offered by field bean (Vicia faba) flowers: Nectar, pollen and operative force. Ecology and Evolution 8: 3161–3171. https://doi.org/10.1002/ece3.3851
Bertazzini M, Forlani G (2016) Intraspecific variability of floral nectar volume and composition in rapeseed (Brassica napus L. Var. oleifera). Frontiers in Plant Science 7: 288. https://doi.org/10.3389/fpls.2016.00288
Burkle L, Irwin R (2009a) The effects of nutrient addition on floral characters and pollination in two subalpine plants, Ipomopsis aggregata and Linum lewisii. Plant Ecology 203: 83–98. https://www.jstor.org/stable/40305717
Burkle L, Irwin R (2009b) Nectar sugar limits larval growth of solitary bees (Hymenoptera: Megachilidae). Environmental Entomology 38: 1293–1300. https://doi.org/10.1603/022.038.0441
Chabert S, Sénéchal C, Fougeroux A, Pousse J, Richard F, Nozières E, Geist O, Guillemard V, Leylavergne S, Malard C, Benoist A, Carré G, Caumes E, Cenier C, Treil A, Danflous S, Vaissière BE (2020) Effect of environmental conditions and genotype on nectar secretion in sunflower (Helianthus annuus L.). Oilseeds & Fats Crops and Lipids 27: 51. https://doi.org/10.1051/ocl/2020040
Clark D, Whitney H, Sutton G, Robert D (2013) Detection and learning of floral electric fields by bumblebees. Science 340: 66–69. https://doi.org/10.1126/science.1230883
Cnaani J, Thomson JD, Papaj DR (2006) Flower choice and learning in foraging bumblebees: effects of variation in nectar volume and concentration. Ethology 112: 278–85. https://doi.org/10.1111/j.1439-0310.2006.01174.x
Elliott SE (2009) Surplus nectar available for subalpine bumble bee colony growth. Environmental Entomology 38: 1680–1689. https://doi.org/10.1603/022.038.0621
Erickson EH (1975) Variability of floral characteristics influences honey bee visitation to soybean blossoms. Crop Science 15: 767–771. https://doi.org/10.2135/cropsci1975.0011183X001500060008x
Gervais A, Fournier V, Bélisle M (2020) Agricultural landscape composition affects the development and life expectancy of colonies of Bombus impatiens. Ecosphere 11: e03142. https://doi.org/10.1002/ecs2.3142
Gillespie S, Long R, Williams N (2015) Indirect effects of field management on pollination service and seed set in hybrid onion seed production. Journal of Economic Entomology 108: 2511–2517. https://doi.org/10.1093/jee/tov225
Jakobsen HB, Kristjánsson K (1994) Influence of temperature and floret age on nectar secretion in Trifolium repens L. Annals of Botany 74: 327–334. https://www.jstor.org/stable/42765453
Kim W, Gilet T, Bush, JWM (2011) Optimal concentrations in nectar feeding. Proceedings of the National Academy of Sciences of the United States of America 108: 16618–16621. https://doi.org/10.1073/pnas.1108642108
Klinkhamer, P. G. L., & van der Veen-van Wijk, C. A. M. (1999) Genetic variation in floral traits of Echium vulgare. Oikos 85: 515–522. https://doi.org/10.2307/3546700
Konzmann S, Lunau K (2014) Divergent rules for pollen and nectar foraging bumblebees – a laboratory study with artificial flowers offering diluted nectar substitute and pollen surrogate. PLoS ONE 9: e91900. https://doi.org/10.1371/journal.pone.0091900
Leiss KA, Klinkhamer PGL (2005) Genotype by environment interactions in the nectar production of Echium vulgare. Functional Ecology 19: 454–459. https://doi.org/10.1111/j.1365-2435.2005.00986.x
Mallinger RE, Prasifka JR (2017a) Bee visitation rates to cultivated sunflowers increase with the amount and accessibility of nectar sugars. Journal of Applied Entomology 141: 561–573. https://doi.org/10.1111/jen.12375
Mallinger RE, Prasifka JR (2017b) Benefits of insect pollination to confection sunflowers differ across plant genotypes. Crop Science 57: 3264–3272. https://doi.org/10.2135/cropsci2017.03.0148
McGoey BV, Janik R, Stinchcombe, JR (2017) Individual chambers for controlling crosses in wind-pollinated plants. Methods in Ecology and Evolution 8: 887–891.
Mitchell RJ (2004) Heritability of nectar traits: why do we know so little? Ecology 85: 1527–1533. https://doi.org/10.1890/03-0388
Nicholls E, Hempel de Ibarra N (2017) Assessment of pollen rewards by foraging bees. Functional Ecology 31: 76–87. https://doi.org/10.1111/1365-2435.12778
Pamminger T, Becker R, Himmelreich S, Schneider CW, Bergtold M (2019) The nectar report: quantitative review of nectar sugar concentrations offered by bee visited flowers in agricultural and non-agricultural landscapes. PeerJ 7: e6329. https://doi.org/10.7717/peerj.6329
Parachnowitsch AL, Manson JS, Sletvold N (2019) Evolutionary ecology of nectar. Annals of Botany 123” 247–261. https://doi.org/10.1093/aob/mcy132.
Pelletie, L, McNeil JN (2003) The effect of food supplementation on reproductive success in bumblebee field colonies. Oikos 103: 688–694. https://www.jstor.org/stable/3548155
Portlas ZM, Tetlie JR, Prischmann-Voldseth D, Hulke BS, Prasifka JR (2018) Variation in floret size explains differences in wild bee visitation to cultivated sunflowers. Plant Genetic Resources 16: 498-503. https://doi.org/10.1017/S1479262118000072
Prasifka JR, Mallinger RE, Portlas ZM, Hulke BS, Fugate KK, Paradis T, Hampton ME, Carter CJ (2018) Using nectar-related traits to enhance crop-pollinator interactions. Frontiers in Plant Science 9: 812. https://doi.org/10.3389/fpls.2018.00812
Real LA, Rathcke BJ (1991) Individual variation in nectar production and its effect on fitness in Kalmia latifolia. Ecology 72: 149–155. https://www.jstor.org/stable/1938910
Rering CC, Franco JG, Yeater KM, Mallinger RE (2020) Drought stress alters floral volatiles and reduces floral rewards, pollinator activity, and seed set in a global plant. Ecosphere 11: e03254. https://doi.org/10.1002/ecs2.3254
SAS Institute Inc (2014) SAS OnDemand for Academics: User's Guide. Cary, NC, U.S.A.: SAS Institute Inc.
Teuber LR, Barnes DK (1979) Environmental and genetic influences on alfalfa nectar. Crop Science 19: 874–878. https://doi.org/10.2135/cropsci1979.0011183X001900060031x
Vogler DW, Peretz S, Stephenson AG (1999) Floral plasticity in an iteroparous plant: the interactive effects of genotype, environment, and ontogeny in Campanula rapunculoides (Campanulaceae). American Journal of Botany 86: 482–494. https://doi.org/10.2307/2656809
von Arx M, Goyret J, Davidowitz G, Raguso RA (2012) Floral humidity as a reliable sensory cue for profitability assessment by nectar-foraging hawkmoths. Proceedings of the National Academy of Sciences of the United States of America 109: 9471–9476. https://doi.org/10.1073/pnas.1121624109
Waller GD (1972) Evaluating responses of honey bees to sugar solutions using an artificial-flower feeder. Annals of the Entomological Society of America 65: 857–862. https://doi.org/10.1093/aesa/65.4.857
Wyatt R, Broyles SB, Derda GS (1992) Environmental influences on nectar production in milkweeds (Asclepias syriaca and A. exaltata). American Journal of Botany 79: 636–642. https://www.jstor.org/stable/2444879
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