استجابة نبات الفاصوليا (Phaseolus vulgaris cv) للإجهاد الملحي في مراحل امتصاص الماء والإنبات ونمو البادرات

Abstract

Salinity stress plays the main environmental limitation to crop productivity in the arid and semi-arid regions of the world. Water uptake which is an important issue of seeds germination and for metabolic processes is effected by water salinity. In this study the effect of water salinity on: water uptake, germination, and seedling growth of bean plant (Phaseoulus vulgaris cv) was evaluated. Seeds of bean were sown in petri dishes (for germination stage) and in pots (for seedling stage). Seeds were treated with three different concentrations of salinity (0, 100, and 120mM NaCl) with completely randomized design in four replications. The present study demonstrated that salinity adversely affected water uptake percentage, seeds germination and seedling growth. Results revealed that salinity decreased water uptake percentage, decreased germination and seedling growth parameters, particularly at high salinity level. The results indicated that the highest water uptake percentage, highest germination percentage, mean daily germination, and germination speed were found in 0 mM NaCl and the lowest water uptake percentage, germination percentage, mean daily germination, and germination speed were found in 120 mM NaCl. Also the results illustrated that plant height changed between 33-16 cm, number of branches changed between 10-4 branch Plant-1, number of leave changed between 26-9 leaf plant-1, plant fresh weigh changed between 23-8 g, and plant dry weigh changed between 7-2 g in beans between 0-120 mM NaCl salt concentrations. The results indicated that seed germination and seedling establishment were inhibited due to the decrease of water potential, which results in the decline in water uptake by seeds, and seed germination was prevented by high level of salinity stress.