Relationship of Soybean Germination and Vigor Tests to Field Performance1

Abstract

AbstractA number of soybean (Glycine max (L.) Merr.) seed vigor tests are available through seed testing laboratories for use by seed producers and farmers. In order to determine if these tests provide more information on field performance than the standard warm germination test, seed lots differing in quality were planted in different field environments at a constant seeding rate (350,000 seeds/ha) and evaluated for percent emergence, final stand at maturity, and grain yield. Several germination tests, including the warm germination test (also evaluated for percent strong seedlings and percent diseased seeds), cold test, accelerated aging test, and tetrazolium test were conducted by seed analysts and statistically correlated with field performance.Experiments were conducted on Cisne silt loam (Mollic Albaqualf) at Brownstown, Ill. and Proctor silty clay loam (Typic Argiudoll) at Urbana, Ill. When the same seed lots were planted at different planting dates and locations, field performance differed markedly depending on seedbed conditions. Stress seedbed conditions were difficult to predict in advance. For example, at one location poorer emergence was observed with a warm, dry seedbed than with a cold, moist seedbed. A greater number of laboratory tests correlated with field emergence in favorable seedbed environments than in unfavorable environments. The cold test showed a consistent high correlation with field emergence and final stand. In general, reduction in yield was associated with a loss in stand. The cold test was the most effective germination test for identifying seed lots that would perform well in the field and should provide more assistance than the standard warm germination test in identifying problem seed lots.