Functional Evaluation of Seed Coating Agents Used for Controlling Wheat Fusarium Crown Rot
Fusarium crown rot has been becoming a most destructive soil-borne disease across main producing areas of wheat in Huang-Huai Plain,severely threating security supply of food grain in China.Resistant varieties to Fusarium crown rot are now rarely available,and the disease control is mainly by applying chemical pesticide.Seed coating is an effective method for Fusarium crown rot.The seed coating agents available for wheat Fusarium crown rot were comprehensively evaluated for their disease control effectiveness and yield incensement,laying a basis for reasonable deployment of chemical pesticides.A highly susceptible Zhengmai 1354 to Fusarium crown rot was selected as the wheat variety tested in this study.The seeds were coated with coating agents and dried before planting.The pathogen inocula were prepared with a highly virulent strain PY20-20 of Fusarium pseudograminearum on millet grain medium.During two consecutive growth seasons,artificial inoculation was conducted by mixing equal amount of treated seeds and inocula together and sowing in a field nursery.The disease progress of wheat plants at each testing plot was rated and recorded at jointing and milking stages,respectively.The disease index(DI)of treatments with nine coating agents at different wheat growth stages was scored.After being harvested,grain yield of each plot was assessed.Their effects on Fusarium crown rot control and yield increase were evaluated along with wheat yield related traits considered.The results showed that DI values of Fusarium crown rot were all less than 1.0 after treatments at jointing stage,being significantly lower than the monk DI value of 5.07.In the agents tested,the control effects of fludioxonil·clothianidin(33 g·L-1),difenoconazole·imidacloprid(9%),and metalaxyl-m·fludioxonil(35 g·L-1)ranged from 97%to 100%.At milk stage,all crown rot DI values of seed coating agent treatments were less than 15,being significantly lower than the DI value of 81.55.The control effects of metalaxyl-m·fludioxonil(35 g·L-1)and difenoconazole·imidacloprid(9%)were averagely higher than 92%and 95%with yield increases of 39%and 36%,respectively.Overall,use of metalaxyl-m·fludioxonil(35g·L-1)and difenoconazole·imidacloprid(9%)will be more effective for Fusarium crown rot control than others,with a better prospect for disease control.
wheatFusarium crown rotseed coating agentdisease indexyield related trait
国家科技期刊平台
NSTL
万方数据
维普
