水稻品种对稻瘟病的抗性研究

水稻品种的抗性鉴定:1973～1977年在稻瘟病圃中,筛选出对穗颈瘟4～5年保持中抗以上的品种15个,1975～1977年又鉴定出对穗颈瘟3年均保持中抗以上的品种47个。在病圃中对大量水稻品种抗性鉴定材料的统计分析表明,籼稻品种的叶片对稻瘟病菌抗侵入和抗扩展能力强的品种数量比粳稻多。穗颈和主轴则不同,在病圃中粳稻叶瘟发生较重的年份,籼稻抗侵入的品种数量比粳稻多,反之,籼稻比粳稻少。但在同一抗病等级中,粳稻造成的损失多比籼稻轻,表现耐病性强的品种数量比籼稻多。根据多年和多点试验,绝大部分品种在不同地区和不同年份之间抗性表现不一致。就叶瘟和穗颈瘟抗性变化情况相比,叶瘟抗性变化较穗颈瘟大。

ON THE VARIETAL RESISTANCE OF CULTIVATED ORYZAE SATIVA TO RICE BLAST DISEASE

Fifteen super-moderating resistant varieties of rice were obtained in the nurseries by screening for resistance to the rice neck blast disease in 1973 to 1977, another 47 super-moderating varieties to neck blast were further selected during the years 1975 to 1977.Results demonstrated that in the Indica cultivars, individuals with leaves strong in anti-penetration and anti-spread abilities to the blast fungus were more numerous in Japonica cultivars. In the year, when the leaf blast of Japonica cultivars was seriously attacked in the blast nurseries, the Indica cultivars showed more individuals with the neck and axisanti-penetration resistance in the same blast nurseries. On the contrary, when the Indica cultivars were severely attacked by the neck and axis blast the Japonica cultivars showed higher tolerance to leaf blast.The expression of resistance to leaf blast or neck blast in most cultivars varied with years and localities. The varietion of resistance to leaf blast fluctuated more distinctly than that to neck blast.