【摘要】 小麦白粉菌分生孢子萌发的温度范围为-2～34℃,最适为10～17℃。分生孢子离体后在2℃5天,7～17℃3天,20℃2天都还有侵染力。分生孢子在0～100%的湿度下都可以萌发,湿度愈大萌发率愈高,尤以在水面萌发率最高。分生孢子侵入寄主的湿度必须在65%以上,湿度愈大发病愈重。分生孢子在pH2.2～12.4的范围内都可以萌发,以pH4.2～7.7最适。紫外光对分生孢子有强裂的杀伤作用。在直射阳光下分生孢子的寿命比散光和黑暗条件下短。分生孢子荫发必须要有充足的氧气。光照能促使分生孢子的形成。在自然条件下,分生孢子形成有昼夜变化的规律,白天形成的孢子数比夜间形成的孢子数约大3倍。分生孢子传播的有效距离力15公里以上,传播的有效高度大于979公尺。更多还原

【Abstract】 The conidia of Erysiphe graminis f.sp.tritici germinated at -2℃ to 34℃(optimum 10℃-17℃)。The dropped onidia might retain the abilityof infection for 5 days at 2℃,for 3 days at 7℃～17℃,and for 2days at 20℃.Although he conidia might germinate in the relative humi-dity of 0～100%,yet the percentage of germination and severity of hedisease was intimately related to the degree of humidity.In the surfacewater film the percentage of germination as he highest.The humidityneeded for infection of wheat was above 65%.The conidia germinated in pH2.2 to pH12.4optimum pH 4.2-7.7).Ultra-violet light killed the conidia.Under the direct solar radiation,thelongevity of conidia as shorter than in the darkness or in the diffusedlight.The germinatien of conidia was in need of plentiful oxygen.In ay-light the formation of conidia was three times in quantity as in night.The distribution of the conidia was found to xcess 150 miles in di-stance and more than 979 meter in height.更多还原