Artificial pre-harvest sprouting chamber with moderate humidity better simulates field sprouting for soft winter wheat

Pre-harvest sprouting, germination of the seed on the spike, causes reduced grain quality and marketability in US wheat. Methods devised to induce and study pre-harvest sprouting vary significantly from one another in procedure, induction time, and/or measurement, and often fail to accurately reflect natural sprouting, which varies over years and locations. An artificial sprouting chamber and protocol with a shorter exposure time and relative humidity more relevant to field conditions was significantly correlated (<i>p</i> < 0.01) with natural pre-harvest sprouting over three years for ten wheat varieties measured by alpha amylase activity. The alpha amylase activities of ten wheat varieties tested under the developed artificial sprouting chamber and protocol were significantly correlated (<i>p</i> = 0.001) with those subjected to overhead irrigated field sprouting tests over three years. Four pairs of the ten varieties were genetically related but showed significantly different sprouting and alpha amylase activity. These varietal pairs may prove useful in studying the genetics of pre-harvest sprouting. While the study was performed in wheat, other susceptible crops such as rice, barley, rye, and sorghum could be tested using this method.