|Tom Pouce Blanc and Tom Pouce Barbu Rogue, two Triticum
aestivum sources of very short straw
Institute of Plant Breeding (I.v.P.), Wageningen, The Netherlands
Two varieties named Tom Pouce Blanc (TPB) and Tom Pouce Barbu Rouge (TPBR) occur in the I.v.P.-wheat collection. They were received by Dr. J.G.Th. HERMSEN from Dr. P. MARTIN, Vilmorin-Andrieux, Massy-Palaiseau, France in 1960. The main feature of these varieties is their very short straw. This character could be used for breeding shortstraw wheat cultivars.
The varieties should not be confused with a Tom Pouce variety mentioned by the N.I.A.B. (1963) and which came from Maison F. Lepeuple in Bersee, France.
A picture of both varieties is given in a figure on the cover, while some of the main characteristics are given in Table 1. Although they are winter wheats they can be grown as transitory wheats. Their big flag leaves are very prominent and this characteristic could also be introduced in modern cultivars.
The ears are of normal length. A normal ear of TPB had 24 spikelets and 41 grains. In general these grains are shrivelled. Seed emergence is low.
Some outcrossing occurs but any illegitimate F1 plant is easily recognized by its length.
The poor seed emergence and the outcrossing may result from the shortness of the plants. The grains developing in the ears can easily be infected by Septoria spores in rain splash, while pollen grains may drop from surrounding tall plants into the florets.
Neither variety carries a dominant gene for hybrid necrosis (ZEVEN 1968) so no necrotic F1's plants will occur.
According to Dr. P. MARTIN (1960) TPB was found in the old English variety Hybrid Carter G. TPBR probably originated from outcrossing in TPB. The origin of Hybrid Carter G is not known to me.