Proline Accumulation Due to Stress at Different Stages of Growth in Five Sorghum Genotypes

Free proline accumulation in leaves under stress induced at different growth stages in two hybrids and their parents of sorghum was studied. It was observed that the magnitude of proline accumulation was high when stress was induced at initial vegetative phase and decreased when at the other stages. Further, relative ranking of the genotypes in proline accumulation varied with the stage at which stress was imposed. Since drought may occur at any stage of the growth period, if estimation of proline is to be used as a screening test, stage at which this is to be done becomes important.