Beckmannia Syzigachne Competitive Characteristics And Green Control In Rice-Stubble-Wheat Field Under Rice Straw Returning

In this study,the rice-stubble wheat field in Jiangsu Province was taken as the research object,studies under the rice straw light spin returning,deep buried returning,and cover returning three ways Beckmannia syzigachne to wheat photo synthetic physiological characteristics and yield effect at wheat different stages.Use whole plant bioassays conducted to measure the effects of mesosulfuron-methyl on different Beckmannia syzigachne regions in chlorophyll content,chlorophyll fluorescence parameters and Rubisco enzyme activity;And add selected 9 additives to 30 g/L mesosulfuron-methyl for liquid contact angle,drying time,surface tension,maximum holding capacity and Beckmannia syzigachne fresh weight control effect.The aim of this study was to explore the green prevention and control methods of Beckmannia syzigachne.Results show that:(1)No Beckmannia syzigachne,compared with no straw returning,three kinds of straw returned mode can improve the wheat yield 5.39%～23.18%,and under the deep buried returning to wheat yield increase is most obvious.Exist Beckmannia syzigachne,the wheat photosynthesis is restrained in the whole growth period,and yield decreased.However,compared without straw mulching,the three straw mulching methods increased the photosynthetic parameters of wheat by 0.48%～55.56%in the whole growing period,and the wheat yield increased by 31.85%～45.15%,the wheat yield increased the most under the condition of straw light spin returning.(2)Under mesosulfuron-methyl stress,there were differences in susceptibility to mesosulfuron-methyl among different regions.After mesosulfuron-methyl 36 g a.i./hm2 dose treatment 10 d,Rubisco activity of Huaian leaf was significant reduced 48.14%,under 9～36 g a.i./hm2 doses,chlorophyll content declined significantly 26.43～47.75%,the biggest photochemical efficiency significantly by 1.13%～2.13%.And Rubisco activity of Gaochun Beckmannia syzigachne leaf compared with the corresponding controls was decreased significantly slower,under 9～36 g a.i./hm2 dose treatment,chlorophyll content decreased significantly by 15.37%～32.59%.Whole plant biological activity determination results show that Huaian Beckmannia syzigachne fresh quality ED90 was 32.745 g a.i./hm2,Gaochun Beckmannia syzigachne ED90 is the biggest 69.116 g a.i./hm2,significantly more than the recommended dose of mesosulfuron-methyl;(3)Add selected adjuvants to mesosulfuron-methyl control Beckmannia syzigachne all have synergistic effect.Under 50%recommended dose of mesosulfuron-methyl(4.5 g a.i./hm2),add the selected adjuvants to mesosulfuron-methyl for Beckmannia syzigachne control effect can be increased by 8.71%一 26.12%;At 75%of the recommended dose(6.75 g a.i./hm2),the control effect was increased by 6.26%～28.13%.At 100%recommended dose(9 g a.i./hm2),the effect was increased by 12.19%～46.34%.Instrument analysis results showed that the fatty alcohol 2 significantly reduced the mesosulfuron-methyl contact angle and surface tension of liquids,improve its holding allowance in Beckmannia syzigachne surface,reduce the drying time of the liquid at the same time.Above all,(1)Under Beckmannia syzigachne competition condition,straw returned can improve wheat photosynthetic capacity,increase the matter accumulation,reducing the loss of production.(2)The Gaochun Beckmannia syzigachne to mesosulfuron-methyl was not sensitivity(3)Add appropriate adjuvant to mesosulfuron-methyl can improve the control effect of Beckmannia syzigachne,help reduce mesosulfuron-methyl usage,perfecting the governance of resistance Beckmannia syzigachne species;As a result,the Beckmannia syzigachne of high stress areas,the appropriate choice straw light spin returning,to reduce weed competition lead to crop failures,at the same time as the dynamic changes of the weed community,can be appropriately used straw deep buried returning,improve the efficiency of weed control;Harm serious region can rotate the Beckmannia syzigachne straw counters-field way can achieve certain control effect of grass,rotation use of herbicides,adding additives to reduce the dosage of herbicide in the herbicide.