1.Engineering Research Center for Protection,Development and Utilization of Characteristic Biological Resources in Hanjiang River Basin,Jianghan University;2.China;3.Huazhong Agricultural University/National Oilseed Rape Engineering Technology Research Center
Foundation project: biological breeding special zd04010 (2022), the national natural science foundation of China (U22A20469) and the national key research and development program (2016 yfd0100202-25).
苗期是油菜植株形态建成的重要阶段, 盐碱胁迫是影响其苗期形态的主要因素之一, 因此筛选出苗期过程中耐盐碱种质对油菜生产及研究具有重要意义。本研究对 286 份甘蓝型油菜品系进行苗期耐盐碱性鉴定,通过水培试验,测定盐碱胁迫处理下叶片数、绿叶数、绿叶比、株高、根 长、根重等指标,通过盐碱胁迫综合评价值(D值)、极端材料筛选分析、相关性、主成分、隶属函数、频数分析和逐步回归分析法,对不同基因型苗期油菜种质建立耐盐碱性综合评价模型并筛选出适宜的评价鉴定指标。盐碱胁迫下,除叶片数与株高相关系数未达到显著性,叶片数与株高、绿叶数呈负相关,其它性状之间均呈现正相关并达到了显著或极显著水平。利用主成分分析法将 7个耐盐碱指标综合成为4个主成分,可代表油菜耐盐碱性88.349%的原始数据信息量。依据4个主成分的相对重要性(权重)进行加权,得到不同基因型的耐盐碱性综合评价值(D值)。结合隶属函数分析和极端材料筛选分析,筛选出4份 耐碱盐的甘蓝型油菜种质和4份盐碱敏感种质。通过逐步回归分析结果认为,在油菜苗期测定其绿叶数、绿叶比、地上重、根长和根重,通过回归方程估算其D值,可以初步判断甘蓝型油菜种质资源耐盐碱性。
Seedling stage is an important stage for the morphology of rapeseed plants, and salinity stress is one of the main factors affecting its seedling morphology, so screening out salinity-tolerant germplasm in the seedling process is of great significance to rapeseed production and research. In this study, 286 kale-type Brassica napus lines were identified for salinity tolerance during the seedling stage, and the number of leaves, green leaves, green leaf ratio, plant height, root length, root weight and other indexes were determined by hydroponic test under salinity stress treatments, and different genotypes of seedling stage oilseed rape germplasm were identified by the comprehensive evaluation value of saline and alkali stress (D-value), screening analysis of extreme materials, correlation, principal component, subordinate function, frequency number analysis and stepwise regression analysis. A comprehensive evaluation model of salinity tolerance was established for different genotypes of seedling oilseed rape germplasm and suitable evaluation and identification indexes were screened out. The correlation coefficients between the number of leaves and plant height were not significant, and the number of leaves was negatively correlated with the plant height and the number of green leaves under saline and alkaline stress, while the correlation coefficients between the number of leaves and the number of green leaves were negatively correlated with the number of green leaves. The seven salinity tolerance indexes were combined into four principal components using principal component analysis, which could represent 88.349% of the original data information of salinity tolerance in oilseed rape. Based on the relative importance (weight) of the four principal components, the combined salinity tolerance evaluation value (D value) of different genotypes was obtained. Combined with affiliation function analysis and extreme material screening analysis, four alkali-resistant kale-type oilseed rape germplasm and four saline-sensitive germplasm were screened out. The results of stepwise regression analysis showed that the salinity tolerance of kale-type oilseed rape germplasm resources could be preliminarily determined by measuring the number of green leaves, green leaf ratio, above-ground weight, root length and root weight at the seedling stage, and then estimating the D-value of the germplasm resources through regression equations.