水稻纹枯病改良新抗源YSBR1的抗性评价

Evaluation of Resistance of a Novel Rice Germplasm YSBR1 to Sheath Blight

从籼粳交后代群体中筛选到一份抗纹枯病水稻新种质YSBR1。多年的大田和温室接种鉴定以及立枯丝核菌毒素对水稻胚根伸长抑制率试验结果均表明,YSBR1的抗性水平极显著高于其他参试品种(系),且稳定、可靠,在大田接种试验中的纹枯病平均病级为2.39±0.23级(按0～9级评价标准),达"抗病"水平。YSBR1的株高为(102±4.32)cm,叶片稍内卷而挺拔,株形优良,生育期适中,在水稻抗纹枯病遗传育种中可有较大研究价值和利用前景。

A novel rice line YSBR1 with resistance to sheath blight （SB） was identified from the progenies of a cross between varieties of japonica and indica. The resistance of YSBR1 to SB was evaluated with multiple replications in the field and greenhouse and inhibition rate of embryo root growth by SB-toxin was investigated also. The results indicated that the resistance of YSBR1 to SB was significantly higher than that of other germplasms tested, and was stable and reliable; the average SB disease score of YSBR1 was 2.39±0.23 and reached ＂resistant＂ grade based on a ＂0-9＂ SB disease rating system. Line YSBRl has an appropriate growth period duration and an improved plant type, with semi-dwarf plant （102 ± 4.32 cm）, slightly rolled and erect leaves. These results suggested that line YSBR1 has potentially high value for study on genetics and can be useful for improvement of resistance to SB in rice breeding.