Abstract:

A pot experiment with controlling water treatments (CWT) for the two cultivars, Shangyu 397 and Suijing 3 at －30 kPa to －35 kPa and －60 kPa to －65 kPa of soil water potential（SWP） monitored by soil negative pressure water potential tester was carried out during tillering period, panicle formation period, 1–10 days after heading, 11–20 days after heading, 21–30 days after heading, 1-30 days after heading, respectively. The results showed that the yield of two cultivars was decreased significantly before heading stages, especially at panicle formation stage by lower SWP, but no longer obvious decrease was observed when SWP continued to be decreased .The yield lower of Shangyu 397 was greater than that of Suijing 3 at tillering stage, however that was in reverse at panicle formation stage. The effect of CWT on grain quality of the two cultivars was greater at panicle formation stage than at other stages, with the lowest comprehensive index embodied quality. Water sensitive stage of yield and quality was panicle differentiation stage. Comparing drought resistance coefficient and comprehensive index of the two cultivars, the effect of CWT after heading stages on quality was greater than that on yield.

Key words: Rice, Soil moisture, Yield, Drought-resistance index, Quality, Comprehensive index embodied quality