Assessing the Effects of Soil Moisture on Germination in Winter Wheat.

Drought is a major challenge in wheat production globally and in Nebraska, particularly during germination. Rapid germination is important for satisfactory stands whereas delayed germination may lead to winter injury and lower yield.  Laboratory experiments were conducted at the University of Nebraska-Lincoln (UNL) to compare germination of five Nebraska-grown wheat cultivars under different soil water conditions.  The cultivars, Anton, Nuplains, Pronghorn, Trego, and Wesley were selected because of their presumed differences in water use efficiency (WUE).  A soil moisture release curve was determined for a silt loam soil to select water treatment levels. The experimental design was 3 water treatments X 5 cultivars factorial that was replicated four times. Seeds and the water treatments were incubated at 21^o C, and germination was measured on the fifth and twelfth day after incubation.  Germination differed significantly among cultivars and water treatments.  A significant interaction was found between cultivars and water treatment (p<0.05).  Anton followed by Wesley showed the highest germination under the highest water stress condition (-1700 kPa). Although, Anton may be a more drought tolerant cultivar, it has a low tolerance to pre harvest sprouting in humid conditions.  However, Wesley may be the best cultivar among those tested because of its high germination under water stress conditions and high tolerance to pre harvest sprouting. Since drought may become more prevalent, and wheat is often grown on soils that have a low water holding capacity, this inexpensive approach can be used to screen wheat genotypes that will lead to the development of drought tolerant wheat cultivars.