Influence of the Environment during Seed Development on the Morphology and Growth Rate of Soybean Seedlings

Abstract

We have examined the effect of the temperature at which soybean plants produced seeds on the morphology and growth rate of plants produced from those seeds. We germinated Fiskeby V seeds at 20 C, then randomly assigned plants to either an 18 C or 25 C controlled environment chamber until they had produced mature seeds. Characteristics of the seedlots produced at 18 and 25 C were then compared in controlled environment chambers with three different thermal regimes and, also, in field trials. Mean seed size and emergence rate did not differ between seedlots. When grown at 25 C in a controlled environment, and when grown in the field, plants grown from the 25 C-grown seedlot had greater axillary stem weight than the 18 C-grown seedlot, at each of three growth stages. Total leaf area and dry weight were greater for the 25 C-grown seedlot than for the 18 C-grown seedlot at one growth stage, when grown in the controlled environment at 25 C and in the field. The results indicated that environment of the parent plants had an effect on the morphology and growth rate of the subsequent generation and indicate that caution should be used in inferring genetic differences between parent populations from morphological differences in the progeny.