Effect of Post-emergence Closed Herbicide Spraying on Wheat Growth and Weed Control
MENG Zili
ZHU Qian
NI Xuefeng
WANG Qi
LYU Xialei
YAN Xiangquan
ZHU Wei
Abstract：To investigate the effects of post-emergence spraying of closed herbicides on wheat growth and weeds,Zhoumai 22 was used as the experimental material.Nine spraying treatments were set up including pyroxasulfone doses of 125(T1),250(T2),500(T3),1 000(T4)and 2 000(T5),and flufenacet doses of 184.5(T6),369(T7),738(T8),and 1 476(T9)(g a.i./hm2),and one blank control.The effects of different herbicides on wheat photosynthetic characteristics,chlorophyll SPAD values,photosynthetically active radiation(IPAR),leaf area index(LAI)and fresh weight,and the chemical control effect of pyroxasulfone on weeds were studied.The results showed that the net photosynthetic rate of leaves under T1 and T6 treatments was higher than that of the control,and the transpiration rate of all 9 treatments was lower than that of the control.The values of T6 and T1 treatments were larger,and the stomatal conductance was highest under T1 treatment.The intercellular CO2 concentration was highest under T9 treatment,and the value was lowest under.T1 treatment.There was a statistically significant difference between T1 treatment and control after 11 days of herbicide application.Under T1,T2,T3,T6 and T7 treatments,wheat IPAR and LAI were higher than those of the control,with the highest values under T1 treatment,which increased by 18.37％and 37.77％respectively,followed by T2 treatment.There was no significant effect on wheat plant height and fresh weight at doses of 125 and 250 g a.i./hm2(T1 and T2)of pyroxasulfone.When the dose is greater than 250 g a.i./hm2,inhibitory symptoms will occur,and the height and fresh weight of wheat plants will be inhibited by different doses of flufenacet.It can be seen that T1 and T2 treatments have little effect on the growth and development of wheat.The control effects of T4,T5 and T9 treatments on the fresh weight of the tested weeds were all higher than 95％,while the control effects of T1 and T6 treatments on wild oats were not significant.Considering the safety of wheat growth and the cost of medication,among the six treatments(T2,T3,T4,T5,T8 and T9)with a fresh weight control effect of＞50％to 95％on Aegilops tauschii and wild oats,and a fresh weight control effect of over 95％on other tested weeds,T2 treatment is recommended for post-emergence spraying in wheat fields.
Keywords：WheatHerbicidePhotosynthetic characteristicPhotosynthetically active radiationWeedChemical control effect
Publication Date：2024-08-28
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：7( 40-46 )