北方白菜型冬油菜的春化率、抗寒性和遗传多样性分析

Vernalization rate,cold tolerance and genetic diversity analysis of winter Brassica rapa L.cultivated in Northern China

以26份北方白菜型冬油菜为材料,通过观察记载冬前植物学性状、测定半致死温度(LT 50),分析冬油菜春播后的春化率与抗寒性的关系,并利用筛选出的SRAP、SSR和InDel标记对参试材料进行聚类和遗传多样性分析。结果表明,白菜型冬油菜植物学性状具有丰富变异,遗传多样性指数Simpson(D)变化范围为0.011~0.847,Shannon-Weaver(H)变化范围0.035~2.046,其中数值型性状叶柄长度的遗传多样性指数最大,非数值型性状生长习性的遗传多样性指数最小。参试材料春化率为6.59%~69.88%,半致死温度-3.52~-9.93℃。相关性分析表明,春化率与LT 50呈极显著正相关(P≤0.01),与生长习性呈显著正相关(P≤0.05),与叶色呈极显著负相关(P≤0.001)。遗传多样性分析表明,26份白菜型冬油菜共筛选出27对引物,共检测总等位基因数130个,有效等位基因数(Ne)平均为3.14,香农指数(I)平均为1.2073,Nei’s基因多样性指数(H)平均为0.6168,多态性信息含量(PIC)平均为0.5681。聚类和主坐标分析将参试材料分为6大类,类群Ⅰ和类群Ⅱ主要是天水育成材料,类群Ⅲ、Ⅳ、Ⅴ和Ⅵ主要是在兰州育成的材料。

Twenty-six northern winter Brassica rapa L.varieties were used as the study materials.We observed botanical characters of seedlings before overwintering,calculated the semi-lethal temperature(LT 50)and analyzed the relationship between cold tolerance and vernalization rate after sowing in early spring.Meanwhile,the selected SRAP,SSR and InDel markers were used to cluster the tested materials.The results showed that there were abundant variations at each of traits of winter Brassica rapa L.,with the Simpson(D)of 0.011~0.847 and the Shannon-Weaver(H)of 0.035~2.046.The diversity index of petiole length was the highest in numeric traits,and that of growth habit was the lowest in qualitative traits.The vernalization rate of the tested materials was 6.59%~69.88%.The LT 50 of the tested materials was-3.52~-9.93℃.Correlation analysis showed that vernalization rate was extremely and significantly positively correlated with LT 50(P≤0.01),significantly positively correlated with growth habit(P≤0.05),but it was extremely and significantly negatively correlated with leaf color(P≤0.001).Genetic diversity analysis showed that 27 pairs of primers were screened from 26 Brassica rapa L.,and the total number of alleles was 130.Moreover,the averaged effective allele number(Ne)was 3.14,and the averaged Shannon’s diversity index(I)was 1.2073.The averaged Nei’s genetic diversity index(H)was 0.6168,and the averaged polymorphism information content(PIC)was 0.5681.According to the clustering and principal coordinate analysis,the tested materials were divided into 6 categories.GroupsⅠandⅡwere mainly raised in Tianshui,while groupsⅢ,Ⅳ,ⅤandⅥwere mainly materials raised in Lanzhou.