GREENHOUSE AND FIELD-EVALUATION OF POD DEHISCENCE IN SOYBEAN

A greenhouse procedure to evaluate differences among soybean [Glycine max (L.) Merr.] genotypes for pod dehiscence (shattering) susceptibili ty permits evaluation under controlled environments. Suitable environm ental conditions do not always exist in the field. The objectives of t his study were to develop a greenhouse method to screen for shattering susceptibility and to compare genotypes for shattering resistance und er both greenhouse and field conditions. Eight genotypes were evaluate d in both the field and the greenhouse. A split-plot treatment design in the greenhouse included watering plants after physiological maturit y versus no watering after maturity as a whole-plot factor, with genot ypes assigned to split plots. In the greenhouse, shattering susceptibi lity was not reduced by watering after physiological maturity. The gen otypes most susceptible to shattering were identified on the basis of the greenhouse and field evaluation. Among the specific genotypes eval uated, the earliest maturing genotypes were not the most susceptible t o shattering.