EFFECTS OF OZONE STRESS ON YIELD FORMATION AND DRY MATTER ACCUMULATION OF RICE UNDER DIFFERENT SOURCE-SINK PROCESSES

摘要

To further investigate the effects of ozone stress on yield and dry matter production in rice in the perspective of different densities and the source-sink relations, Shanyou 63 and Ilyou 084 were chosen as test materials relying on advanced paddy ozone FACE (Free Air Gas Concentration Enrichment) technology platform. The results indicated that high concentrations of ozone reduced sharply panicles per unit area of Shanyou 63, sipkelet number per panicle of Ilyou 084, spikelets per unit area, seed setting rate, 1000-grain weight, yield, dry matter accumulation in maturity period of both two varieties; however, it had no significant effect on panicles per unit area of Ilyou 084, sipkelet number per panicle of Shanyou 63, and harvest index of the two varieties, suggesting ozone and source-sink process had a significant influence on the yield and dry matter accumulation in maturity. These results demonstrated that under high concentrations of O-3, dropped rice production was mainly associated with dramatic decline of spikelets per unit area and seed setting rate; ozone stress on rice escaped from the density adjustment; constraints of photosynthesis source resulting from clipping treatment exacerbated ozone stress on rice biomass and ultimately lead to the loss of production.