单株籽粒丰产甘蓝型油菜理想株型构建研究

Construction of an ideal plant type of Brassica napus with high rapeseed yield per plant

为了探明影响油菜单株籽粒产量的株型因素,构建单株籽粒丰产甘蓝型油菜理想株型,对湖南有代表性的3个甘蓝型油菜品种,进行了3个不同肥力的处理,通过无损测量的方式获得了81个植株苗期、初花期、盛花期、角果期等4个生育期的,包括叶面积、角果面积、籽粒产量等在内的11个株型指标,并开展了相关株型研究。对不同生育期相关株型指标进行分析,探明了相关株型指标的基本生长规律。对与籽粒产量相关的株型指标进行了分析,发现不同生育期的诸多株型指标与其呈极显著相关,其中角果期各分枝籽粒产量、角果数、分枝长和角果面积与单株籽粒产量均呈极显著正相关,且各分枝相应株型指标的相关系数呈相似变化规律;分枝数、叶面积、绿叶数、根颈粗和株高与单株籽粒产量均呈极显著正相关性,且相关系数按不同生育期呈现相应的变化规律;分枝高度和分枝相对高度与单株籽粒产量呈极显著负相关,分枝段相对长度与单株籽粒产量呈极显著正相关。分析了单株产量前10%和20%的植株相关特征和生长规律,除分枝高度和分枝相对高度明显降低外,其他株型指标较总体样本相应指标均不同程度地增加,产量前10%样本与产量前20%样本表现出相似规律,只是相应值增加或减少的幅度更大。对不同生育期油菜理想株型特征采取了定性加定量的方式进行描述,理想株型具有“光合器官(叶、角果)表面积大,根颈粗壮、分枝位低、相对抗倒,二次分枝以及相应角果数明显增多”等特征。从光合效能原理、形态结构原理和源、库、流原理等三个方面对油菜理想株型形成的原理进行了分析,并对油菜理想株型的构建策略、应用方法、研究存在不足进行讨论。

This study aimed to identify the plant type factors that affect grain yield per plant of Brassica napus and to develop an ideal plant type for high-yield rapeseed per plant.Three different fertility treatments were carried out on three representative varieties of B.napus in Hunan.Eleven plant type indexes including leaf area,pod area,and rapeseed yield of 81 plants at four growth stages(seedling,initial flowering,full-blooming,and pod-filling stages)were obtained by non-destructive measurement.Based on an analysis of the relevant plant type indicators at different growth stages,the basic growth laws of the relevant plant type indicators were explored.The plant type indexes related to rapeseed yield were analyzed,and it was found that several plant type indexes at different growth stages were significantly correlated with them.Among them,rapeseed yield,pod number,branch length,and pod area of each branch at the pod stage were significantly positively correlated with rapeseed yield per plant,and the correlation coefficients of the corresponding plant type indexes of each branch showed similar variation trends.Branch number,leaf area,green leaf number,root-neck thickness,and plant height were significantly positively correlated with rapeseed yield per plant,and the correlation coefficient showed a corresponding trend according to the different growth stages.Branch height and relative height of the branch were significantly negatively correlated with rapeseed yield per plant,and the relative length of the branch segment was significantly positively correlated with rapeseed yield per plant.The related characteristics and growth rules of the first 10%and 20%rapeseed yields per plant were analyzed.Except that the branch height and the relative height of the branches were significantly reduced,the other plant type indexes were increased to different degrees compared with the corresponding indexes of the overall samples.The first 10%of the yield samples and the first 20%of the yield samples showed similar trends,but the corresponding values increased or decreased more.Ideal plant type characteristics of B.napus at different growth stages were qualitatively and quantitatively described.The ideal plant type has the characteristics of a“large surface area of photosynthetic organs(leaves and pods),strong root-neck,low branch position,strong lodging resistance,secondary branches,and the increased corresponding pod number”.The formation principle of the ideal plant type of B.napus was analyzed from three aspects:photosynthetic efficiency,morphological structure,and source-sink-flow principles.The construction strategy,application method,and research shortcomings of the ideal plant type of B.na pus were discussed.