甘蓝型油菜矮秆新品系DW871在两环境下收获指数及相关性状分析

为打破瓶颈,提高收获指数从而提高油菜籽粒产量,利用甘蓝型油菜矮秆新品系DW871为材料,解析它在2个不同环境下(思南和花溪)收获指数的构成因素,分析在思南和花溪环境下各相关性状的变异,利用相关分析和通径分析研究产量收获指数与农艺性状的关系。结果表明,思南环境下DW871株高、主花序长度、主花序角果数、分枝角果数、单株角果数和收获指数均值显著高于花溪环境,但二次有效分枝数、角果长度和单株生物产量则显著低。思南环境下,油菜收获指数较高的主要原因是相对湿度和温度较高,导致生物产量较低、角果多、单株产量较高,对产量贡献较大,单株角果数和单株生物产量与收获指数呈极显著负相关;而在花溪环境,单株角果数与收获指数呈极显著正相关,单株生物产量无显著相关性。两种环境下,千粒重和单株产量都与收获指数呈极显著正相关。综合分析表明,高温高湿环境下,将角果长度、主序角果数和二次分枝数与单株产量有效结合,且适当控制生物产量才能实现较高的收获指数;多日照、降雨量充足环境下,则可通过提高单株角果数、角果长度和单株产量来提高,同时也需对生物产量进行适当控制。

Harvest index and correlation analysis for Brassica napus new dwarf line DW871 in 2 environments

To break the bottleneck and improve rapeseed harvest index, DW871(a new Brassica napus dwarf line) was studied under 2 conditions. Variation was analyzed on related characteristics investigated at Sinan and Huaxi sites. Relationship between yield harvest index and agronomic characteristics by correlation analysis and path analysis showed that DW871 plant height, length of main inflorescence, silique number in main inflorescence,branch silique number, silique number per plant and average yield index were significantly higher in Sinan. But the secondary effective branch number, silique length and plant biomass in Sinan were significantly lower. Under Sinan environment, higher harvest index came from higher relative humidity and temperature, which resulted in low biological yield, more pods and higher plant yield, and all these contributed to greater yield. Silique per plant and plant biomass were negatively correlated with harvest index. In Huaxi environment, silique per plant had significantly positive correlation to harvest index, with no significant correlation between plant biomass. In both environments, 1000-seed weight and plant yield were positively correlated with harvest index. In high temperature and humidity environment, comprehensive analysis showed that, to improve the harvest index, it was necessary to combine silique length,silique number in main inflorescence and secondary branches with plant yield effectively, and to control the biological yield properly. In multi-day sunshine and sufficient rainfall environment, high harvest index of DW871 could be achieved by increasing plant silique, silique length and the number of silique per plant, it also could be improved by increasing plant yield, and by properly controlling biological yield.