Amanda de Oliveira Silva, Small Grains Extension Specialist
Pre-harvest sprouting is the onset of grain germination while still on the wheat head. Once wheat reaches physiological maturity, it can initiate germination if exposed to ideal moisture and warm temperatures for a few days. This is the case in some areas of Oklahoma that have received rainfall for several days after wheat has ripened. Genetics and environmental conditions are responsible for the differences in susceptibility to sprouting. Thus, wheat varieties differ in their resistance to sprouting (i.e., some are more prone to sprouting than others).
The occurrence of pre-harvest sprouting damage in the state has been low to moderate so far. But, due to the number of questions/calls I have received with the same concern in the past days, I thought I would share a few thoughts.
Can I use sprout-damaged wheat for seed?
It depends on several factors, but more importantly, is the level of sprout damage that has occurred. Grains that are swollen and with split seed coat, without visible root or shoot emerging from the seed, might still be viable to be used as seed. In this case, a germination test is warranted after harvest and before planting. Suppose the grain shows broken seed coat with visible roots and/or coleoptile. In that case, it should not be kept for seed because they will likely have reduced viability or not be viable at all (Picture 1).
Will pre-harvest sprouting damage affect quality?
The extent to which pre-harvest sprouting grain will affect quality depends on the level of damage. Grain germination causes the production of alpha amylase, an enzyme that breaks down starch. As the level of sprout damage increases, this enzyme also increases, leading to an impairment of grain quality. Sprouted damaged grain can negatively impact wheat flour and baking quality by affecting mixability, crumb strength, loaf volume, etc.
Contact your local county Extension office.
Gary Strickland, Jackson County Extension Director and SWREC Regional Agronomy Specialist
Glen Calvert , Extension Educator Ag/4H at Washita County