FLOOD TOLERANCE OF NEWLY DEVELOPED SEMI-DEEP LOWLAND RICE VARIETY (VARSHADHAN) DURING SEED GERMINATION AND SEEDLING STAGE

Abstract

In this study, newly developed rice cultivar (Varshadhan) was evaluated for flood tolerance during seed germination and seedling stage in the presence and absence of SUB1. Under flooding, the rate of seed germination was 100 per cent in both SUB1 and non-SUB1 line of Varshadhanas in the normal condition. And also, we noted that there was no significant difference in growth promotion in terms of shoot and root between SUB1 and non-SUB1 line under flooding. In the gene expression analysis, expression of RAmy3C, Adh1 and Adh2 genes was continuously induced up to 72 h in both rice lines under normal and flooding condition. Furthermore, in another screening for flood tolerance at seedling stage, higher survival rate was noted in Sub1 line and lower rate in non-Sub1 line. In gene expression analysis also, expression of Sub1A gene was induced strongly in SUB1 line but not in non-SUB1 line. Thus, Varshadhan rice cultivar with SUB1 has played significant role in flood tolerance during seed germination as well as seedling stage. Therefore, this cultivar will be suitable in rice growing areas where farmers facing flooding during seed germination and seedling stage.