Research On Screening Identification And Resistant Mechanism To Glyphosate-resistance In Wild Soybean Resources

Field weed is one of the main causes in agricultural production and economicbenefits all the time. It is difficult to develop an efficient, safe and environmentalherbicide. Furthermore, the herbicide-resistant crops could reduce the application ofchemicals so as to protect the environment and improve crop production. Glyphosateis one of the most widely used herbicide, which has the advantages of high efficiency,low toxicity, and destructive broad-spectrum. Glyphosate-resistant crops couldobtain higher economy as well as social value.425wild soybean materials in greenhouse were conducted forglyphosate-resistant screening and physiological and biochemical measurements todetermine the mechanism of resistance, which would provide a theoretical basis andexperimental materials for further cultivation and herbicide-resistant soybeanbreeding in this research. The results showed that the obvious differences existed inthe wild soybean materials on glyphosate resistance. It deduced that there mightpossess the natural resistance genes in these wild soybeans.Thirty five wild soybean materials of better resistant were screened byobserving survival and injury symptoms, which sprained glyphosate diluted600times. To elucidate the physiological mechanism of the resistance，photosyntheticpigments contents, shikimate accumulation MDA content and gultathione Stransferases (GSTs) activities between glyphosate-resistant and sensitive wildsoybeans were basically identified before glyphosate treatment for sensitive line2012-89and resistant line2011-32. Under varied glyphosate concentrationtreatments，photosynthetic pigment contents and shikimate accumulations remainedstable. MDA contents indicated a downward trend after the first rise and GSTsactivities significantly enhanced for resistant soybean line2011-32．However, in line2012-89, both shikimate accumulation and photosynthetic pigments contentssignificantly increased while MDA contents showed an increased trend and GSTsactivities minor changes. The results supported that the shikimate accumulations, and photosynthetic pigments contents expressed stable, and the enhancement ofMDA contents and GSTs activities might be the main physiological responses forglyphosate resistance in wild soybeans.The resistant and sensitive materials of wild soybean for were conductedgermination test screening indoor. Germination rate of resistant materials was higherthan that of sensitive materials. It could germinate with yellowing withered spots andnone of lateral root, which had injury symptoms in the dilution of glyphosateconcentrations20times. However, Sensitive materials could not germinate normally.To some extent, the germination test indoor could be used to identify betterscreening glyphosate-resistant wild soybean materials. The further research shouldbe focused on the resistance mechanism by spraying glyphosate after cultivation.