The results indicated that genetic background was vulnerable among rice male sterile lines in large scale.It suggested that the heterosis were limited for these CMSs in hybrid breeding.

• 24份细胞质雄性不育系聚类分析结果表明，目前在生产中应用的细胞质雄性不育系遗传背景比较单一，杂种优势利用潜力有限。