Growth ability of rapeseed(Brassica napus L.)seedlings under late-sowing condition
Planting winter rapeseed after double cropping rice,ratooning rice or/and late-maturing japonica rice,might encounter problems of delayed sowing,lower temperature,and delayed growth in late autumn and winter,resulting in decrease yields.In order to select rapeseed varieties that tolerant to late sowing,48 breeding lines of Brassica napus with different maturity periods were selected,and outdoor nutrient solution hydroponics and field di-rect seeding were designed under late sowing(Nov.11).Biomass and field yield in autumn and winter were mea-sured,and their growth ability to tolerate late sowing was compared.Results of outdoor nutrient solution hydroponic cultivation showed that there were rich genetic variations in their low-temperature growth,and biomass accumula-tion at 30,60,and 90 days after transplantation was significantly positively correlated with yield per plant at maturi-ty.The biomass of early and middle maturing types at 30 and 90 days was significantly less than that of late matur-ing type.The 60-day biomass of early maturing type was significantly less than that of late maturing type.The SPAD value of leaves of late maturing type was significantly higher than those of early and middle maturing type at 30 days.In order to select rapeseed varieties tolerant to late sowing,the 30-day biomass accumulation capacity of plants could be an index in the early stage of rapeseed breeding to improve breeding efficiency.Results of field di-rect seeding showed that yield per plant of the early maturing type was significantly lower than that of middle matur-ing type.By comparing the biomass accumulation rules of different ecological types of rapeseed at seedling stage un-der the late sowing,it provides theoretical guidance for the late sowing and high yield cultivation of rapeseed and va-riety selection.
Brassica napusbiomass accumulationlow temperatureSPAD value
万方数据
维普
