STUDIES ON THE PHYSIOLOGY-OF SEED GERMINATION IN PHASEOLUS VULGARIS L

Abstract

The physiology of seed germination and subsequent growth of seedlings have been studied in kidney bean (Phaseolus vulgaris L.). Application ofNaCl salinity was done as a tool to clarify further insights on the mechanisms achieved under normal conditions and their possible modificaiton under salinity stress. Germination potential of five kidney bean cultivars was evaluated and Giza 3 was selected for further experiments. Depression of growth under salinization of soil could be mainly attributed to retardation of photosynthetic performance, decrease of the activity levels of auxins, gibberellins and cytokinins as well as to enhancement of growth inhibitors, particularly abscisic acid (ABA). Consequently, further work was performed to show the effect of exogenous application of ABA and the growth retardant cycocel (CCC), known as an antigibberellin, on the protein patterns of kidney beans in absence and prevalence ofNaCl salinity. This might be assumed to indicate the extent to which the regulation of gene expression is involved in the control of seed germination and seedling growth under stress conditions.