Study On The Germplasm Identification And Physiological Mechanism Of Herbicide Resistance Of Maize Inbred Lines Before Seedling Stage

This research studys the identification of herbicide resistance in maize seedlings and its physiological mechanism of resistance in view of herbicide phytotoxicity problem before maize seedlings in the field production recent years.This research adopts the field experiment,71 maize inbred lines as materials,set up 5 kinds of treatment:acetochlor + 2,4-D + atrazine,acetochlor,2,4-D,atrazine,water.Measure its morphological and physiological 17 single parameter in the maize seedling for the comprehensive evaluation of the herbicide resistance and maize herbicide resistance physiological mechanism research.Shennong 52134(T1654)as resistance type material,Shennong 52100(T1650),Shennong 52084(T1646),Shennong H357(T1666)as sensitive materials,set up 5 kinds of treatment:acetochlor+2,4-D+ atrazine,acetochlor,2,4-D,atrazine,water.Measure related physiological indicators for maize herbicide resistance physiological mechanism research to resistance materials and sensitive materials.The research main conclusion as follows:1.According to herbicide-resistance coefficient of all indexes,the 17 single indexes were transformed into 6 independent comprehensive components through principal component analysis,The membership function method and cluster analysis were employed to divided the 71 maize inbred lines into 4 types.7 maize inbred lines were the resistance type.25 maize inbred lines were the medium resistance type.38 maize inbred lines were the low sensitive type.1 maize inbred lines was the sensitive type.Based on the stepwise regression analysis,9 indexes closely related to the herbicide-resistance,including chlorophyll value,aboveground dry weight and underground part dry weight,total root length,root number of bifurcate,soluble sugar content,MDA content,SOD activity,POD activity.And the optimal regression equation was established:D=0.323+0.087X3+0.061X4+0.054X5+0.072X6+0.079X11+0.027 X13+0.012X,4-0.037X15+0.023X16(F=899.295,P=0.0000,R2=0.993)?2.By comparing the respective processing and comparison,found that resistance materials and sensitive materials of soluble sugar content,MDA content,SOD activity,POD activity and proline content,the chloroplast pigment content were higher than control treatment;Through the comparison of resistant materials and sensitive material,found that the physiological indicators of herbicide sensitive materials under processing in the five sampling period is generally higher than resistant materials;As the change of sampling time,the physiological indicators vary along with the change of time,MDA content,SOD activity,POD enzyme activity and proline content performance was decreased,soluble sugar content and the chlorophyll content in rising trend.