Heat Stable Proteins and Desiccation Tolerance in Recalcitrant and Orthodox Seeds

Abstract

During development ofpeanut seeds, a set oflow molecular weight polypeptides was identified most ofwhich were heat-stable. For wampee seeds, only one band ofheat-stable proteins could be checked out by SDS-PAGE. It had a molecular weight of 20 kDaand constituted 1% ofthe total proteins. By Western blot analysis, wampee seed axes can express dehydrin-like proteins (at 67-88 days (d) after anthesis) but the level was very low. Stachyose and sucrose increased and maltose declined with the acquisition ofdesiccation tolerance during embryogenesis ofpeanut seed. Following the development of wampee seed, glucose and maltose decreased gradually, while fructose, sucrose and stachyose increased markedly. It may be assumed that the heat-stable and low molecular weight polypeptides synergize with soluble sugars in the acquisition ofdesiccation tolerance in peanut seed though not in wampee seed.