Pre-harvest sprouting in wheat. I. Influence of cultivar, rainfall and temperature during grain ripening

Abstract

Tolerance to pre-harvest sprouting, measured by the response of grain in intact harvested ears to a standard wetting treatment, varied substantially from season to season and in all trials declined with time after harvest ripeness. The major factor associated with the observed variation in tolerance at harvest and the decline after harvest ripeness appeared to be the level of grain germinability. Statistical analyses of meteorological data relating to the 10- and 20-day periods prior to harvest and the period from harvest to wetting treatment, indicated that most of the seasonal variation in tolerance could be explained in terms of the amount of rain during the 20-day period prior to harvest. The potential to use this relationship to develop an early warning system for wheat growers together with implications for wheat breeding and cultivar improvement programs are discussed.