标题：EFFECT OF RHIZOBIUM. NANO SILICA AND ASCORBIC ACID ON MORPHO-PHYSIOLOGICAL CHARACTERS ANDGENE EXPRESSION OF POX AND PPO IN FABA BEAN
(VICIA FABA L.) UNDER SALINITY STRESS CONDITIONS
摘要：Faba bean (Vicia faba L.) is one of the greatest important leguminous plants used for human nutri- tion in Egypt, which is the fourth important legumi- nous crop in the world after dry bean, dry peas and chickpea. Salt stress affects all major processes and metabolism in plants, so these experiments were car-ried out in 2018/2019 and 2019/2020 to study the in- fluence of ascorbic acid (200 and 300 mg/L), Rhizo-bium and nano silica (2 and 3 mM) on the physiolog-ical. biochemical parameters and gene expression of peroxidase (POX) as well as polyphenol oxidase (PPO) in faba bean plants under salinity conditions (0, 2000 and 4000 ppm) on Giza 3 cultivar. The re- sults showed that salinity stress adversely affect var- ious morphological and physiological characters in- cluding stem height, number of leaves, number ofbranches, chlorophyll content and relative water content as well as yield components, whereas elec- trolyte leakage increased in salt-stressed plants. The application of ascorbic acid (200 mg/L), Rhizobium and nano silica (2 mM) markedly improved growth parameters, physiological characteristics and yield components of stressed plants compared with un- treated stressed plants. A significant reduction in electrolyte leakage was also recorded for all treat- ments. It was also observed from the results that the gene expression of peroxidase (POX) and polyphe- nol oxidase (PPO) was high in plants treated with nano silica, ascorbic acid and Rhizobium, however, there was a decrease in the gene expression in the stressed untreated plants. Our results revealed the important role of nano silica, ascorbic acid and Rhi- zobium in enhancing faba bean growth and tolerance to salinity stress.
