Study On The Survival Competition Among Transgenic Drought Resistent Soybean,C₄ Weed Amaranthus Retroflexus L. And C₃ Weed Abutilon Theophrasti Medic

Under the background of global climate change,the impact of drought is expanding,drought has become the bottleneck problem of increasing the yield for soybean.The cultivation of transgenic drought resistant soybean has important practical significance to solve the production problem of soybean yield and quality reduction caused by drought.Weeds are an important part of the farmland ecosystem,and compete with crops for natural resources such as light,water and nutrients.Study on the competitive relationship between DREB3 transgenic drought resistant soybean and weeds,the competitive relationship between receptor Dongnong50 and weeds aimed to provide basic data for environmental safety evaluation of transgenic drought resistant soybean.C₃ weed?Abutilon theophrasti Medic?and C₄ weed?Amaranthus retroflexus L.?as experimental materials,study the competitive relationship between soybean and weeds in light,water,photosynthetic characteristics and nutrient content.The main results were as follows:1.Under drought stress and sufficient water condition,compared with the soybean,weed has a significant competitive advantage in biomass,soil water content,light intensity and nutrient content.Among them,C₄ weed?Amaranthus retroflexus L.?had more depressing influence on the biomass of soybean,had more depressing influence on moisture content of where belowde the surface 15 cm.Effect of soybean on light intensity at different heights,C₃ weed?Abutilon theophrasti Medic?had greater effects than C₄ weed?Amaranthus retroflexus L.?.2.Under drought stress and sufficient water condition,soybean has little effects for weed on biomass,soil water content,light intensity and nutrient content.Soybean did not have the competitive advantage.3.Under drought stress and sufficient water condition,compared with the C₄ weed?Amaranthus retroflexus L.?,C₃ weed?Abutilon theophrasti Medic?has greater biomass in root and shoot.C₄ weed?Amaranthus retroflexus L.?has higher content in N,P and K.Photosynthetic rate of Amaranthus retroflexus L.was significantly higher than that of Abutilon theophrasti Medic.And it has obvious competitive advantage for underground nutrients.Compared with C₃ weed?Abutilon theophrasti Medic?,C₄ weed?Amaranthus retroflexus L.?can better adapt to drought conditions.4.Under drought stress and weed competition,root and shoot dry weight,photosynthetic rate and the contents of N,P,K were significantly decreased for soybean.There was nodifference in root and shoot dry weight,photosynthetic rate and the contents of N,P for C₄ weed under adequate water conditin.C₃ weed no significant difference in photosynthetic rate and the contents of N,P.5.Under drought stress,compared with C₃ weed?Abutilon theophrasti Medic?and C₄ weed?Amaranthus retroflexus L.?,transgenic drought resistant soybean showed no competitive advantage on plant growth,photosynthetic rate,and nutrient.Transgenic drought resistant soybean does not have the characteristics of weeds.