INFLUENCE OF ANTIOXIDANTS PRE-SOWING ON BIOCHEMICAL AND SEED VIGOR OF SOME RICE (Oryza sativa, L.) VARIETIES UNDER SALINITY

Abstract

A new protein bands and Esterase banding pattern could be used as a biochemical marker for selecting tolerant rice cultivars to be grown under salt conditions, and, treatment rice seed with ascorbic and salicylic acids greatly alleviate the harmful effect of salt stress on rice plant. In this study, three ric cultivars (Giza 177, Sakha 103 and Sakha 104) were selected to determine the interactive effects of salinity (0.4 and 10 ds/m) ,ascorbic and salicylic acids on Esterase isoenzymes , pattern protein synthesis and seed vigor. Laboratory experiment was conducted at Seed Technology Research Department during 2010 year. The results revealed that one new band (Est 3 isoenzyme) was detected of both Giza 177 and Sakha 103 cultivars (untreated seed) under salt stress. Salinity treatments induced synthetic 3 and 2 new protein bands of Giza 177 and Sakha 103 (untreated seed), respectively. No new bands were obtained of Sakha 104 (untreated seed). Protein with molecular weight of 49 KD could play an important role in triggering a system to tolerate sever stress of salinity. Treatments of seeds of Giza 177 and Sakha 103 cultivars with salicylic or ascorbic acid induced one Esterase3 isoenzymes (RF 0.9). Three unique bands were observed under salinity with molecular weight 86, 93 and 132 KD of (Giza 177 + salicylic), (Sakha 103 +Ascorbic) and (Sakha 104+Ascorbic), respectively. It could be summarized that only under saline conditions, Pre-sowing rice seed of Sakha 104 cultivar with Ascorbic produced the highest germination percentage, speed germination index, germination rate and seedling dry weight and the lowest mean germination time as well as time 50 % germinated seed compared with other two cultivars under study.