interactive effect of water stress and each of ABA, alar and proline on certain metabolic activities in red radish plants

ABSTRACT

The interactions between each of ABA; 2 ppm [growth inhibitor], alar; 500 ppm [growth retardant] and proline; 100 ppm [amino acid] and water stress were undertaken in a trial to find out the best means in overcoming the injurious effect of soil drought on red radish plant. Under drought condition, the different treatments mentioned above caused remarkable increases in soluble sugars [reducing sugars and sucrose], polysaccharides, total sugars, 2-oxo-acids, amino-N, total soluble-N, total-N and protein-N above those of the untreated stressed plants, except that ABA-treated leaves contained less amounts of sucrose, at the later two ages, as compared with the untreated stressed ones. Moreover, foliar spraying of the stressed plants with both alar and proline resulted in the accumulation of each of P, Mg, Ca, Fe, B and Cu, with the exception that alar reduced the Cu values below the control amounts. In response to ABA treatment, P, Fe and B levels were elevated while Mg, Ca and Cu levels were decreased as being compared with those of the stressed untreated plants. Alar was found to be, the most effective applied chemicals for alleviating the adverse effect of drought on most of the metabolic activities of red radish plant