Study On The Difference Of Resource Utilization In Different Evolution Types Of Soybean

Competition is a common phenomenon in farmland.In this study,wild soybeans,semi-wild soybeans and cultivated soybeans with different degrees of evolution were used as the research objects.The effects of mixed soybeans with different degrees of evolution on photosynthetic physiology,sugar metabolism,nitrogen metabolism and grain yield of soybeans were studied.Referring to the research method of competition in plant ecology,the changes of competitive ability among soybeans with different degrees of evolution were analyzed.The results were as follows:In the initial flowering stage（R1）and initial pod stage（R3）,the mixed planting increased the net photosynthetic rate and leaf area per plant of semi-wild soybean,and decreased the net photosynthetic rate and leaf area per plant of wild soybean.When cultivated soybean was mixed with semi-wild soybean,the net photosynthetic rate and leaf area per plant of cultivated soybean decreased;when mixed with wild soybean,net photosynthetic rate and leaf area per plant of cultivated soybean increased.Therefore,the photosynthetic capacity of three kinds of soybeans with different evolutionary degrees was:semi-wild soybean>cultivated soybean>wild soybean.In the R1 and R3 periods,the mixes increased leaf sucrose and starch contents,leaf sucrose phosphate synthase（SPS）,sucrose synthase（SS）,acid convertase（AI）,and neutral convertase（NI）activities in semi-wild soybean and decreased leaf sucrose and starch contents,leaf SPS,SS,AI,and NI activities in wild soybean.The leaf sucrose and starch contents,leaf SPS,SS,AI and NI activities of cultivated soybean decreased when the cultivated soybean was mixed with semi-wild soybean,while the leaf sucrose and starch contents,leaf SPS,SS,AI and NI activities of cultivated soybean increased when the cultivated soybean was mixed with wild soybean.This indicates that the mixed planting increased the carbon metabolizing enzyme activity and photosynthetic product content of semi-wild soybean and decreased the carbon metabolizing enzyme activity and photosynthetic product content of wild soybean,and the carbon metabolizing enzyme activity and photosynthetic product content of cultivated soybean depended on the type of mixed planting soybean.In both R1 and R3 periods,the mixed planting increased leaf NR and GS activity and nutrient（N,P,K）content of semi-wild soybean and decreased leaf NR and GS activity and nutrient（N,P,K）content of wild soybean.The leaf NR and GS activities and nutrient（N,P,K）contents of cultivated soybean decreased when mixed with semi-wild soybean,while the leaf NR and GS activities and nutrient（N,P,K）contents of cultivated soybean increased when mixed with wild soybean,indicating that the mixed planting pattern promoted the leaf N-metabolizing enzyme activities and nutrient uptake of semi-wild soybean and inhibited the leaf N-metabolizing enzyme activities and nutrient uptake of wild soybean.The nitrogen metabolism and nutrient uptake capacity of the three evolved soybean species were as follows:semi-wild soybean>cultivated soybean>wild soybean.In the R1,R3 and R7 periods,mixed planting increased the yield per plant and grain number of semi-wild soybean,and decreased the yield per plant and grain number of wild soybean.When cultivated soybean was mixed with semi-wild soybean,the yield per plant and grain number of cultivated soybean decreased;when mixed with wild soybean,the yield per plant and grain number of cultivated soybean increased.In the mixed mode,dry matter accumulation per plant of semi-wild soybean and cultivated soybean increased,and dry matter accumulation per plant of wild soybean decreased at R1,R3 and R7.The Harvest Index（HI）showed that the harvest index of semi-wild soybean increased,the harvest index of wild soybean and cultivated soybean decreased under the mixed cropping pattern,and the decrease of wild soybean was significantly higher than that of cultivated soybean.The above results showed that the mixed cropping pattern promoted the biomass accumulation,yield characteristics and harvest index of semi-wild soybean,inhibited the biomass accumulation,yield characteristics and harvest index of wild soybean,and the influence on the biomass accumulation and yield of cultivated soybean mainly depended on the adjacent plant species,but the harvest index decreased.Therefore,the nutrient absorption and yield characteristics of three kinds of evolution degree soybean were:semi-wild soybean>cultivated soybean>wild soybean.The competitiveness indexes of three evolutionary soybeans were analyzed,and the results showed that the Relative Yield（RY）of wild soybean was less than 1,the Relative Yield（RY）of semi-wild soybean was more than 1;when cultivated soybean and wild soybean were mixed,the Relative Yield（RY）of cultivated soybean was more than 1,when cultivated soybean and semi-wild soybean were mixed,the Relative Yield（RY）of cultivated soybean was less than 1.Aggressivity（AG）of cultivated soybean to wild soybean,semi-wild soybean to wild soybean and semi-wild soybean to cultivated soybean is always greater than 0,AG_BZ>AG_ZY>AG_BY;Competition Ratio（CR）always greater than 1,CR_ZY>CR_BZ>CR_B.The Relative Severity of Competirion（RSC）and Relative Competition Intensity（RCI）of wild soybean were higher than that of cultivated soybean,namely RSC_YZ-Y>RSC_YZ-Z and RCI_YZ-Y>RCI_YZ-Z;wild soybean and semi-wild soybean were mixed,RSC_YB-Y>RSC_YB-B and RCI_YB-Y>RCI_YB-B;semi-wild soybean and cultivated soybean mixed,RSC_BZ-B<RSC_BZ-Z和RCI_BZ-B<RCI_BZ-Z.Therefore,the competitive ability of three kinds of evolution degree of soybean is different,and the competitive ability level is:semi-wild soybean>cultivated soybean>wild soybean.