【摘要】 以相对发病率和相对病情指数（ＲＤＩ）为指标，比较了三轮半姊妹（ＨＳ）家系和全姊妹（Ｓ１）家系的油菜菌核病抗（耐）性水平。病圃诱发（菌丝体喷雾）条件下，ＨＳ家系群和Ｓ１家系群的平均ＲＤＩ为１１６．８～１７２．２，家系间ＲＤＩ变幅为４０．２～４０８．５。在９６ＨＳ和９６Ｓ１家系群中分别有３０．６％和３９．０％的家系ＲＤＩ小于１００，其中有些家系的病情指数仅为抗性对照的４０％。单株表型选择可为选择提供较大的变异基础，但以ＨＳ和Ｓ１家系病害鉴定为依据的选择，能更为显著地改善群体抗性水平。相同年份田间和病圃条件下的ＲＤＩ呈极显著正相关，但不同年度间ＲＤＩ相关不显著。更多还原

【Abstract】 Evaluation was made to the resistance level of halfsib families and fullsib families derived from 3 cycles of recurrent selection in Brassica napus using relative disease percentage and relative disease index (RDI). Under the condition of induced infection in disease nursery the average RDI of groups of HS and S 1 families varied from 116.8 to 172.2, and the range of RDI among the families was 40.2～408.5. The proportions of families with lower disease index of resistance control in HS and S 1 groups were 30.6% and 39.0% respectively, and some typical families among them only had 40% of disease index of resistance control. Mass selection for sclerotinia resistance could provided a wide variation while the selection based on assessment of HS and S 1 families improved more efficiently the resistance level of populations. There was significant positive correlation between nursery and field disease assessment results (RDI) in the same year, but the correlation of RDI between years under the field conditions was not significant.更多还原