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通过1983～1986年的研究表明:小麦纹枯病的田间流行基本符合“S”形曲线。四年来的综合模式为:Xt=1-1/1+0.0032e~(0.0389t)。其发生主要受品种、菌源量、寄主密度、气候条件等因子的影响。由于该病在我区低坝河谷区发生已较普遍,菌源十分广泛,我区主栽品种均不抗病,当地尚无防治习惯,菌量会逐年累积;今后几年内不可能培育出十分抗病的品种。预计在“七五”期间,此病在我区的发生面积将逐年增加,危害程度将日趋严
According to the research from 1983 to 1986, the field epidemic of wheat sheath blight basically accorded with “S” curve. Four years of the integrated model: Xt = 1-1 / 1 + 0.0032e ~ (0.0389t). Its occurrence is mainly affected by species, source of bacteria, host density, climatic conditions and other factors. As the disease occurred in the low valley area of our district has been more common, a wide range of sources, the main cultivars in our district are not disease-resistant, there is no local control practices, the cumulative amount of bacteria will be accumulated year after year; it is impossible in the next few years to develop very Disease-resistant varieties. It is estimated that during the “Seventh Five-Year Plan” period, the occurrence of this disease in our district will increase year by year, and the degree of harm will be increasingly severe