LIMITS TO RETENTION OF FERTILIZED FLOWERS IN FABA BEANS (VICIA-FABA L)

Factors affecting the retention of faba bean flowers and their develop ment into pods werde investigated. Racemes were scored for the date of anthesis of the first flower, and at maturity, the number of pods tha t developed. These data were correlated with meteorological data. The primary determinant of whether a flower would be retained was the weat her during the 4 days from anthesis: incident light and rainfall accou nted for over 55 % of the variation in the retention of flowers within a genotype. The results help to validate the model that the availabil ity of assimilate at the time of pod setting is critical for the devel opment of adequate yield. In some environments, such as the winter-rai ny Mediterranean climate, available light at flowering may be a major yield-limiting factor.