Plant growth, metabolism and adaptation in relation to stress conditions. XX. comparative effects of salinity on growth, metabolism and yield of three different bean plants

ABSTRACT

The effects of increasing NaCl concentrations [up to 1.5 percent being equivalent to 255 mM] on growth, yield and chemical composition of three different bean plants [Glycine max var. Crowford, Phaseolus vulgaris var. Giza 3 and Phaseolus vulgaris var. Contender] have been studied. Thus, all growth, development and yield parameters appeared to remain unaltered, accelerated or, in most cases, suppressed with particular significance. These changes appeared to be dependent on [1] the concentration of NaCl, [2] the plant tested and 3 the stage of plant growth and development. Teatrnent of the three bean plants with various salinity levels led to marked changes in the total amounts and in the relative composition of carbohydrate and nitrogen pools in shoots and the yield of beans. Variable changes were also obtained for the contents of oil as well as for the constituent saturated and unsaturated fatty acids. Moreover, the results of seed protein fractionation showed marked changes in the composition of polypeptides with a wide range of molecular weights. In conclusion, the following sequence of plants soybean > kidney bean > bush bean appears to be displayed with respect to the degree of tolerance to salinity