| The diagnosis of wheat major diseases, influence factors such as cultivars, fertilizers, fungicides on wheat sharp eyespot, the relationship between disease index and yield loss, the relationship between disease index and kilograin weight, forecast and controlling decision on wheat sharp eyespot and wheat head scab in Anhui were studied in detail, respectively, and the results were reported in this paper.The resistant(endurant) difference of most commercial cultivars and those would be released in near future to wheat sharp eyespot(Rhizoctonia cerealis) was compared. The results showed that the cultivars tested had significant difference to wheat sharp eyespot, but there were no high-resistant cultivars. According to the results, the resistance of all these cultivars to wheat sharp eyespot could be classified into 3 types. The first was susceptible, including Wangmai 38, Wangmai 19, Yangmai 5, Yangmai 158; the second was mid-susceptible, including Wangmai 30; and the third was resistant, including Yumai 18, Yumai 21, Ningmai 9312.The fertilizer trial indicated that, on the basis of definitely nitrogenous fertilizer and phosphorous fertilizer, increasing potassic fertilizer properly could decrease wheat sharp eyespot; and on the basis of definitely potassic fertilizer and phosphorous fertilizer, the more the nitrogenous fertilizer used, the severer the disease was. Given that the corrected coefficient of low kalium was 1, the corrected coefficients of middle and high kalium were 0.96 and 0.90, respectively. Given that the corrected coefficient of high nitrogen was 1, the corrected coefficients of middle and low nitrogen were 0.87 and 0.75, respectively.The relationship between disease index of wheat sharp eyespot and percentage of yield loss was studied. The results showed that the percentage of yield loss rised with the increasing of disease index, and the kilograin weight was the contrary. On the basis of the results mentioned above, the model for disease index and yield loss ratio, disease index and the kilograin weight was established, respectively.In this paper, the forecast for wheat head scab was studied systematically. According to the experts experience and the historical data derived from Xuanzhou, Guangde, Dangtu, Liuan, Feidong, Lujiang, Qianshan, Susong, Fenyang, Yingshang in Anhui, the relationship between meteorological factors and the final severity of wheat head scab were analyzed by means of stepwise discrimination analysis. The results showed that the final severity had closely relation to average temperature often days, rainfall often days in the period from November to April. The mid-long-range forecast models , short-range forecast models for the wheat head scab in south Anhui, middle Anhui, southwest Anhui and the region along Huaihe river in Anhui were set up, respectively. The forecast verification of the mid-long-range corresponding to historical data was 97.83%, 89.29%, 100%, 95.24%, respectively. The forecast verification of the short-range corresponding to historical data was 82.76%, 77.19%, 97.62%, respectively. According to the verifying by General Plant Protection Station of Anhui Province, accuracy of mid-long-range, short-range was 72.41%, 80%, respectively.The control effects of single and mix-fungicides on wheat sharp eyespot were studied in this paper. The results showed that the control effect (CE) of seed treatment by 5%Celest ertra was the best among single-fungicides, the control effect at jointing stage was 72.75%, and the sustained period of CE was the longest. The CE of seed treatment by 11% No.3 mix-fungicides was the best among mix-fungicides, and the CE at jointing stage was 59.81%. The CE of spraying at jointing stage by 20% No.5 mix-fungicides at the dosage of 900ml/hm2 was superior to the CE of spraying by others. The CE of seed treatment by 28% No.l added spraying by 20% No.5 at jointing stage and pre-booting stage was the best in different treatments. The results also showed that seed treatment with 2 times spraying by fungicides(at jointing stage an...
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