Abstract:

The physiological mechanism of drought resistance in the north super japonica rice 'Shennong265' were observed, this study takes the super rice 'Shennong265', and 'Fengjin' which is famous for good quality and taste for materials, with the method of pots cultivating in three levels of soil water potential controlled artificially, well watered (w), moderate water deficit (m), and severe water deficit (s). By varying degrees of water treatment in the grain filling stage to compares the differences of the physiological response. Results showed that, compared with 'Fengjin', moderate stress, in 'Shennong265' the content of chlorophyll was higher 5.03%, the content of soluble protein, soluble sugar and endogenous hormone (IAA+GA3+ZR)/ABA ratio were lower 32.4%, 11.41% and 33.33% than 'Fengjin'. Severe stress, in 'Shennong265' the content of chlorophyll and soluble protein were higher 6.38% and 20.2%, the content of soluble sugar and endogenous hormone (IAA+GA3+ZR)/ABA ratio were lower 51.5% and 25%. The results showed that, 'Shennong265' had strong osmotic adjustment ability, severe stress, soluble protein may play a major role, at the same time, 'Shennong265' increased the content of ABA in the relatively high level of (IAA+GA3+ZR), which not only enhancing the ability of adapt to the drought, also delaying the aging, and make it with stronger ability of resistance drought.