Isolation,Identification Of Pathogen And Control Technique On Oat Covered Smut

Oats are an advantageous specialty crop for both grain and feed.Ustilago spp.is an important factor limiting the high yield and quality of oats.Fomesin and seed dressing are commonly used in production to control the disease,but the effect decreases with age.Therefore,the experiment was conducted to isolate the pathogenic species and analyse its biological characteristics,and to study its integrated control measures in terms of identification of resistant varieties,agricultural measures and screening of efficient chemical agents,aiming at screening safe,efficient and low-toxic alternative agents and combining the use of resistant varieties and agricultural control measures to improve the prevention effectiveness while and reduce the use of chemical agents,so as to provide safe,The aim is to provide safe,efficient and environmentally friendly green control measures for oat black spot.The results were as follows:1.The results of a survey of the damage caused by oat firm black spike disease showed that the diseased plants were significantly shorter than normal plants and that the seeds were filled with dark brown winter spores and covered externally with a strong,unbreakable,dirty black film.The winter spores are brown and spherical.The morphology and molecular biology of the winter spores were identified as Ustilago hordei,and the optimum temperature for germination was10°C,the optimum p H was 5,and the optimum carbon and nitrogen sources were glucose and peptone.2.The results of the two consecutive years of firm black ears disease resistance identification show that the 30 germplasm resources have obvious differences in resistance.7 varieties are immune,namely,Qing Yan 1,Oat-Evoy 126,Dam Yan 5,Dam Oat 18,Dam Oat 5,Grass Oat 1,Dam Oat 3;2high-susceptible varieties,namely,Mongolian Oat No.2,and Yankee No.2.The resistance of skin oats was higher than that of naked oats.3.The toxicity test results of several fungicides showed that the inhibition rate of pentazolol was the highest（99.11%）when the concentration was 120μg/m L,the EC₅₀was the lowest（0.113 ug/m L）,followed by methylthiobacillam（10.4969 ug/m L）.The EC₅₀values of formetrix,Pyrimethil and imidamine were 119.11 ug/m L,12.958 ug/m L and21.59 ug/m L,respectively.Field control results showed that nitrilobazol,carbendazim,methylthiobacillam,formediazone,pyrimidin,imidamine and other agents could reach100%.The highest net income was 430 g/L pentazolol SC,with a net income of 1016.03yuan;Followed by 70%methylthiobacillam WP and 40%nitrile WP,the net income was984.40 yuan and 983.89 yuan,and the other net income was slightly lower.Microbial preparation 500 g/L Bacillus subtilis WP had the lowest net income,which was 867.55yuan.