甘蓝型油菜种质资源田间耐渍性评价和耐渍种质资源筛选

Evaluation of field waterlogging tolerance and selection of waterloggingresistant germplasm resources of Brassica napus L.

甘蓝型油菜是我国最重要的油料作物之一,其生产过程中具有较高的渍害发生风险。为了评价甘蓝型油菜田间耐渍性以及筛选稳定的耐渍种质资源,本研究首先在盆栽条件下确定了苗期耐渍性鉴定的适宜渍水时间,随后在大田试验中对505份种质资源进行了田间耐渍性的综合评价和比较,并筛选了稳定的极端材料。盆栽试验结果表明,甘蓝型油菜的生长在渍水超过4 d时开始受到影响,在渍水约10 d时生长受到严重抑制。2年的田间试验中,利用无人机表型采集平台提取到27个指标,通过因子分析将其转化成了2个公因子,公因子1代表了甘蓝型油菜渍水条件下的生长状态,公因子2代表了生理状态。根据2个公因子的载荷与方差贡献率计算出的耐渍性综合评价值(D值)将甘蓝型油菜种质资源的耐渍性划分为4个类型。其中,极端耐渍型(Ⅰ型)包含99份种质资源、耐渍型(Ⅱ型) 200份种质资源、敏感型(Ⅲ型) 187份种质资源、极端敏感型(Ⅳ型) 19份种质资源。通过2022年的大田试验对上述结果进行进一步验证和筛选,共鉴定到9份稳定的渍水敏感材料和9份稳定的耐渍材料。而且, 2年的试验结果显示植被指数MTVI2D、MCARI2D与耐渍性综合评价值(D值)相关性都高于0.76,可用于对油菜耐渍性快速、高效的综合评价。总之,本研究建立了甘蓝型油菜田间耐渍性评价体系以及耐渍性快速和综合评价方法,解析了甘蓝型油菜种质资源的耐渍性类型,鉴定到了稳定的耐渍和敏感材料,为甘蓝型油菜耐渍性的研究和遗传改良提供了可靠的评价方法和重要的种质资源。

Brassica napus L.(B.napus)is one of the most important oil crops in China,and has high risk of waterlogging stress during its production.The objective of this study is to evaluate the field waterlogging tolerance and screen stable waterlogging-resistant germplasm resources.The appropriate waterlogging duration for waterlogging tolerance identification was determined under pot conditions first,and then the comprehensive evaluation and comparison of the waterlogging tolerance of 505 germplasm resources of B.napus were carried out.The stable extreme materials were screened in field experiments.The results showed that the growth of B.napus plants began to be affected after four-day-waterlogging,and severely inhibited after about 10-day-waterlogging under pot conditions.In the two-year field experiment,27 indexes extracted using the UAV phenotype acquisition platform were converted into two common factors by factor analysis.The common factor 1 represented the growth state of B.napus under waterlogging,and the common factor 2 represented the physiological state.The comprehensive evaluation value of waterlogging resistance(D-value),which was calculated according to the load and variance contribution rate of the two common factors,divided the waterlogging resistance of B.napus germplasm resources into four types,including extremely waterlogging resistant type(Cluster I,99 materials),waterlogging resistant type(Cluster II,200 materials),sensitive type(Cluster III,187 materials),and extremely sensitive type(Cluster IV,19 materials).In the two-year field experiment,nine stable waterlogging sensitive materials and nine resistant materials were identified,and the results were confirmed by the field experiments in 2022.Moreover,in the two-year experiment,the vegetation indexes,MTVI2D,and MCARI2D had high correlations with the D-value,and the correlation coefficients were greater than 0.76,which can be used for rapid and efficient comprehensive evaluation of B.napus waterlogging resistance.In conclusion,the evaluation system and rapid and comprehensive evaluation methods for waterlogging tolerance of B.napus in the field were established,which were applied to analyze the types of waterlogging tolerance of B.napus germplasm resources and identify the stable waterlogging resistant and sensitive materials in this study,providing reliable evaluation methods and important germplasm resources for the research and genetic improvement of waterlogging resistance of B.napus.