Effects Of Different Cultivation Measures On Herbicide Reduction Of Allelopathic Rice

In order to study whether water managements and planting densities of allelopathic rice could reduce the herbicide application.Field experiments of early and late season were conducted in the village of Zahngcun(the year of 2016)and Xiaogangcun(the year of 2017)Xinhui area,Jiangmen City.The rice materials,three Allelopathic rices such as Allelopathy rice No.3,Hualiangyou 78(hybrid composition),N Liangyou 201(hybrid composition)and three common conventional rices such as Yuxiangyouzhan,Baixiangzhan,Wushansimiao,were treated under two different water managements(WN,paddy field drainage during rice booting stage,WS,continuous irrigation during rice booting stage),and two different planting densities(DN,local conventional planting density,DH,high planting density).And then investigated their yields,qualities,and the occurrence of weeds after reducing the application of herbicide.The result showed as follows:(1)After reducing 50% herbicide under the treat of continuous irrigation during the booting stage,the effect on the plant height of allelopathic rice was not significant,however it was significantly on the conventional rice Wushansimiao at the peak time of tillering and the effect gradually decreased with rices growing.The treatment could decrease the tillers of Allelopathy rice No.3 at the early tillering stage under the conditions of 50% herbicide reduction,and the effect gradually decreased with rices growing.Under the condition of 50% herbicide reduction,High planting density has no significant effect on the plant height.But it could significantly reduce the per plant tiller numbers of allelopathic rice which were similar to 100% herbicide,and with the rices growing,the difference was more obvious.(2)After 50% reduction of herbicide,the treat of continuous irrigation during the booting stage and high planting density could effectively control the occurrence of weeds.There was no weed in the whole growth period in the test area,and in the blank control area 50% herbicide reduction in conjunction with continuous irrigation during the booting stage had obvious control effect on weeds after transplanting rice plants for 75 days.No weeds occurred after 50 days of transplanting,and after transplanting 75 days,the weed biomass was also less.50% herbicide reduction in combination with continuous irrigation during the booting stage could effectively inhibit the occurrence of gramineous weeds and other weeds,and the inhibition of gramineous weeds is even more obviously.(3)After 50% reduction of herbicide,high planting density increased the number of effective panicles in rice but reduced the number of grains per spike,which was similar to the treatment of 100% herbicide.But the effect of the compositions of rice yield was not significant under the treat of continuous irrigation during the booting stage compared to 100% herbicide.In general,reducing the application of 50% herbicide with high planting density and continuous irrigation during the booting stage had the effect of stabilizing or increasing yield of Allelopathy rice No.3.(4)After 50% herbicide reduction,the result of continuous irrigation during the booting stage could significantly increase the milled rice rate of Allelopathy rice No.3,and significantly reduced the chalky rice rate and chalkiness degree.And significantly increased the chalky rice rate of N Liangyou 201,reduced its chalkiness size and chalkiness degree.The treatment of high planting density was similar to the 100% herbicide,which could increase the chalkiness degree,chalky rice rate and chalkiness size of allelopathic rice.