Drechslera Avenae Occurrence And Control

Oats (Avena sativa) which is a annual forage crops are rich in nutrients. It makes an improtion role in medical treatment and health care. The leaf spot of oats caused by the necrotrophic pathogen Drechslera avenae (Eida) Sharf, is a fast spteading oat disease and made lot of casualty of oats production in the north of China.In this paper, we understand the laws of the occurrence and control oats leaf spot. Now, we draw the following conclusion:(1) We found that different varieties of oats have a different resistance to oat leaf spot. The same variety in different areas is also different in the oat leaf spot investigation in the north of China.(2) Proof for pathogenic fungi is Drechslera avenae by phenotype and molecular appraisal. The three strains (R1, H44, B8) can grow in5℃-30℃, and the optimum temperature is25℃. They can make use of both glucose and polysaccharide. They also can use N source except (NH4)2CO3to grow. They can grow on a large range of pH conditions, which are the trend of the decrease in diameter with the increase of the acid and alkaline colonies.(3) Using the model of no-till farming covered can reduce the happening of the oats leaf spot. Through orthogonal test,the main factors of influence the oats leaf spot happening is sowing period by the results of the survey in the three years of2009-2011. The influence of irrigation water and fertilizer N ratio is no specific rule. And the effects of irrigation water and P ratio is no significant difference. This is also similar to the orthogonal experiment results coincide, and proof of irrigation water and fertilizer is not significant effects on oat leaf spot occurrence.(4) In Inner Mongolia, shanxi and hebei area planted39kinds of oat varieties in the resistance survey, which26kinds of oat varieties showed the high resistance. Some kinds of disease have an different resistance performance in different regions. BaiYan2and2004R-17all steady represented the high disease resistance in WuChuan and JiNing. In the2011year survey, Ding Yin1and yan2009represented a relatively weak disease resistance.In shanxi and hebei area, a Ba You1, Ba You3, BaiYan2, Yi Pin1and Ba You13are the five varieties which are immune varieties. In the survey, the Ba yan4, Ba You8and Ba You5are Susceptibily varieties of the oat leaf spot, and H44and BaiYan2are moderate to the oat leaf spot. (5) Fungicides toxicity determination shows that50%procymidone and58%metalaxyl mancozeb have good inhibition to mycelial growth of R1. When the antibacterial rate of50%is EC50were0.404and0.712u g/ml, obviously lower than other selected the fungicides. That means50%procymidone and58%metalaxyl mancozeb have potential application value.(6) Fungicides dressing seed is better that fungicides ospraying on the prevention and control of oats leaf spot, and dressing seed can bring a large increase of the production. According to the analysis,40%carbendazim is the best one to control the Drechslera avenae in the field.