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对玉米小斑病的重要流行环节—孢子萌发侵入、病斑潜育显症扩展进行了定量研究。结果表明:叶面渗出物和花粉对孢子萌发及附着胞形成有明显的促进作用。叶面保湿时间(x)和附着胞形成率(y)的关系大体呈一“S”型曲线,两者关系可用回归方程y=exp〔-4.497exp(-0.098x)〕描述。温度(x)和附着胞形成率(y)的关系呈单峰曲线,两者关系可用回归方程y=sin(-3.371x+0.376x2-0.004x3)描述。随着生育期的推进玉米对小斑病侵染的抵抗力增强。增施磷、钾肥可降低小斑病的侵染率。小斑病在玉米上的潜育期为4~6 d,显症期约为7 d;病斑日龄(x)与病斑长度(y)的关系呈倒“J”型曲线,两者关系可用回归方程y=sin(42.645x-10.940x2+0.950x3)描述。
Quantitative research was carried out on the important epidemic link of the small spot disease of corn - invasion of spore germination and expansion of lesion spots. The results showed that foliar exudates and pollens promoted the spore germination and appressorium formation. The relationship between foliar moisturizing time (x) and adherent formation rate (y) is generally an “S” curve. The relationship between the two can be described by the regression equation y = exp [-4.497exp (-0.098x)]. The relationship between temperature (x) and attachment formation rate (y) showed a single peak curve, the relationship between them can be described by the regression equation y = sin (-3.371x + 0.376x2-0.004x3). With the promotion of growth period, the resistance of maize to spot blotch infection is enhanced. Increased phosphorus and potassium fertilizer can reduce the incidence of small spot disease. Smaller spot on maize was 4 ~ 6 days and the symptom was about 7 days. The relationship between lesion’s age (x) and lesion length (y) was inverted J curve, The relationship can be described by the regression equation y = sin (42.645x-10.940x2 + 0.950x3).