Effects Of Waterlogging Stress On Growth And Yield Formation Of Sesame

Waterlogging is the first stress factor which seriously endangering world sesame production, waterlogging at early blooming and full blooming will significantly affect sesame’s each organs built, thereby affecting the final yield. Thence, Ensure early blooming and full blooming impact on morphological and physiological traits of sesame, for solving famers due to waterlogging caused the problem of sesame yield significant decrease has important theoretical significance and application prospects.The pot experiment was conducted with two different waterlogging tolerant varieties of sesame (nonwaterlogging tolerant variety Zhengzhi 13 and waterlogging tolerant variety Zheng 98N09) as research materials, at early blooming and full blooming were waterlogging 12h、24h and 36h. Under waterlogging, masuring different waterlogging tolerant varieties of sesame’s ecological indicators, such as plant height, leaf age, leaf area index, chlorophyll content of leaf, dry matter accumulation etc. Statisticsing different waterlogging tolerant varieties of sesame’s yield traits, such as capsules, grains per capsules, 1000-grains weight, yield etc.The results were as follows:(1) After waterlogging 12h、24h、36h at early blooming and full blooming, The result showed that all of the waterlogging treatment was lower than that of control, which consists of plant height, leaf age, leaf area index, chlorophyll content of leaf, dry matter accumulation. Waterlogging treatment reached significant level (P<0.05). With the waterlogging time prolonging, every ecological indicators gradually decreased.After waterlogging 36h at early blooming, the waterlogging index of plant height, le-af age, leaf area index, chlorophyll content of leaf, dry matter accumulation of nonwaterl-ogging tolerant variety Zhengzhi 13 and waterlogging tolerant variety Zheng 98N09 we- re respcticely 29.51% and 23.73%,32.35% and 26.87%,87.59% and 84.91%,42.16% and 33.83%,76.92% and 68.30%; After waterlogging 36h at full blooming, the waterlogg- ing Index of them were respcticely 6.90% and 5.79%,21.33% and 17.91%,86.17% and 78.27%,39.23% and 38.13%。Waterlogging at early blooming and full blooming will affect the normal growth of sesame, With the waterlogging time prolonging, the impact increased. The sensitivity of different varieties of sesame to waterlogging stress is non waterlogging tolerant variety> waterlogging tolerant variety.(2) Waterlogging at early blooming and full blooming will reduce above-ground dry matter accumulation, With the waterlogging time prolonging, aboveground nitrogen accumulation gradually decreased. Early blooming waterlogging will increase the nitrogen content of stem and grain, instead reduce the nitrogen content of leaf; Full blooming waterlogging will increase the nitrogen content of stem, instead reduce the nitrogen content of leaf and grain. Meanwhile affected by waterlogging, reducing the nitrogen accumulation of leaf and grain, nitrogen accumulation of stem was increased after waterlogging 12h and 24h; But then decreased sharply, nitrogen accumulation of stem was significantly increased after waterlogging 36h;(3) With early blooming and full blooming waterlogging time prolonging, three sesame yield components have decreased continuously to varying degrees which lead to the decline of sesame production. Waterlogging 36 hours on sesame yield components has significantly affected. After waterlogging 36h at early blooming, the capsules, grains per capsules and 1000-grains weight of nonwaterlogging tolerant variety Zhengzhi 13 have decreased to 61.1%,94.3% and 90.9% of control. And the Capsules, Grains per capsules and 1000-grains weight of waterlogging tolerant variety Zheng 98N09 have decreased to 72.5%,94.6% and 92.4% of control. After waterlogging 36h at early blooming, the capsules, grains per capsules and 1000-grains weight of Zhengzhi 13 have decreased to 83.5%,84.9% and 90.4% of control. And the capsules, grains per capsules and 1000-grains weight of Zheng 98N09 have decreased to 86.5%,87.2% and 91.8% of control. After waterlogging 36h at early blooming, the yield per plant of nonwaterlogging tolerant variety Zhengzhi 13 and waterlogging tolerant variety Zheng 98N09 have decreased to 53.7% and 63.5% of control. After waterlogging 36h at early blooming, the yield per plant of nonwaterlogging tolerant variety Zhengzhi 13 and waterlogging tolerant variety Zheng 98N09 have decreased to 53.7% and 63.5% of control.there are significant differences in the early blooming waterlogging and full blooming flowering waterlogging on the three sesame yield components. After the early blooming waterlogging, three components are affected by waterlogging. The influence degree in order is capsules>1000-grains weight>grains per capsules. After the full blooming waterlogging, three components are affected by waterlogging too. The degree of influence in order is 1000-grains weight> capsules> grains per capsules.