Vernalization of Green Plants of a Winter Wheat

Abstract

SPRING cereals differ from winter cereals in their ability to initiate ears immediately under a favourable day-length, without cold treatment of the seed. Unvernalized winter cereals will eventually initiate ears, but even under the most favourable conditions this has not been found to occur until 6–8 weeks after planting¹. ‘Vernalization’ or cold treatment of the just-sprouted seed before planting will eliminate this period of delay before ear initiation, and field studies certainly suggest that the growing plant is also capable of responding to cold treatment during this period^2–5. However, direct evidence of the response of the green plant of the winter cereal to cold treatment is scanty. (Possibly Gunar and Krastina⁶ have evidence on this point, but this is not clear from the abstract available to me.)