【摘要】 1987,1988两年对全国重要稻区稻瘟病菌对异稻瘟净抗药性的测定表明:稻瘟菌敏感菌株平均抑制中浓度为15.38μg/ml,30μg/ml 异稻瘟净抑菌率>52.87%;抗异稻瘟净菌株平均抑制中浓度较异稻瘟净菌株高2倍,为46.00μg/ml,30μg/ml 异稻瘟净抑菌率<51.46%。在南方双季稻区存在大量抗异稻瘟净菌株,其中在广西平南县抗性菌株频率达91.67%,而单季稻区抗性菌株频率最高只有10%。稻瘟病菌抗异稻瘟净菌株在部分地区仍呈上升趋势。研究表明,30μg/ml异稻瘟净可用作抗性监测中的鉴别浓度。更多还原

【Abstract】 A 2 year investigation of resistance to IBP in Pyricularia oryzae Cav.from important ricecultivation areas of China in 1987 and 1988 showed that the most resistant isolates werefound in double-harvest rice areas,with the highest frequency of resistant isolates（FRI）of91.67% in Pinnan County of Guangxi Zhuang Autonomous Region,compared to that of10% in Taixian County in Jiangsu Province,the highest of all single-harvest rice areas.Theaverage EC₅₀of IBP to sensitive isolates was 15.3μg/ml,while that to resistant ones was46.0μg/ml;In toxity equation y=a+logx of sensitive isolates,a=4.7039-1.0664b,where-as in resistant ones,a=4.4675-1.5467b.39μg/ml IBP is suggested for identifying resistantisolates with the inhibition of mycelial growth less than 51.465.更多还原