Effect of dominant weeds on wheat growth characteristics under different planting densities and fertilization treatments
[Objective]This study,with an investigation of the effects of planting density,fertilization,and neighboring weed species identity on wheat growth,is aimed to provide scientific guidance for wheat cultivation.[Method]With wheat(Triticum aestivum)and two dominant weed species[wild oat(Avena fatua)and barnyard grass(Echinochloa crus-galli)]selected as target species,a competition experiment was conducted between pairs of wheat and weeds,by setting four planting densities(4,8,12 and 16 plants·pot-1),four wheat-weed planting ratios(25％:75％,50％:50％,75％:25％and 100％:0),as well as with or without nitrogen addition.After growing for about six months,the total biomass,plant height,leaf and root functional traits of wheat were measured.[Result](1)In monoculture or mixtures with weed species,individual wheat's biomass decreased with the increase of planting density and the proportion of wheat(P＜0.05)(i.e.,the occurrence of negative density dependence).(2)For individual wheat plants grown in monoculture,fertilization significantly increased their biomass and leaf area(P＜0.05)while for those grown in mixture with wild oats or barnyard grass,fertilization had the trend to increase the biomass,root length and root surface area,which did not depend on weed species identity.(3)The interaction effects of planting density,proportion,and fertilization significantly affected wheat root length and area,but demonstrated no effects on other traits.[Conclusion]Fertilization enhanced wheat's aboveground traits in monoculture and belowground traits in mixed cropping,with consistent negative density dependence in both systems.This indicates that agricultural management outcomes are influenced by weed interactions.[Ch,4 fig.1 tab.38 ref.]
万方数据
维普
