Study On Temperature Requirement And Light Energy And Temperature Production Efficiency Of Early And Middle Maturing Rapeseed

In the middle and lower reaches of the Yangtze River,the early maturing rape varieties must be used for the direct seeding cultivation under the mode of rice and rice oil cultivation.Shengguang127 and Huayouza9 were used in this study.Different sowing date,density and nitrogenous fertilizer were set to research the requirements of accumulated temperature for individual growth and development,the influence of accumulated temperature on dry matter accumulation and distribution and light energy and temperature production efficiency.And then analysis the effect of different agronomic measure on ontogenesis,population structure,and yield of early-maturing rapeseedseed.This study can provide theoretical basis and technical support for high yield cultivation of early-maturing rapeseedseed.1 The effect of different agronomic measures on growing periods and accumulated temperature requirement of early-maturing rapeseedseed.Days of whole period decrease 2-4 days with the increase of sowing density.In detail,days of seedling period were decreased,but the situation of stem elongation period were on the contrary.Among different density sets,the largest difference of days may reach 10 d and 9 d for seedling period and stem elongation period,respectively.The requirement of accumulated temperature of seedling stage and whole period was decreased.Days of whole period increased 2-4 days with nitrogenous fertilizer amount increased from 0 to 450 kg/hm~2.In detail,days of seedling period were decreased,the situation of stem elongation period were on the contrary.Accumulated temperature requirement of seedling stage decreased with the increase of nitrogenous fertilizer amount.But situations in other periods were different,the requirement of accumulated temperature were changing among different sowing date,change rules were inconsistent.2 The effect of different agronomic measures on organ development and accumulated temperature requirement.With the nitrogen fertilizer increased,accumulated temperature requirement of the fastest leaf emergence heightened.Under the early sowing condition,treatment N360 got the maximum total leaf number,31.8 pieces.Under the late sowing condition,the total leaf number increased with the increase of nitrogen application,and there were 2.2 pieces differences between N0 and N450 treatments.With the density increased,the total leaf number decreased.In the early sowing date treatment,the total leaves of were 31.1 pieces and 24.8 pieces for 1.5×105planhts/hm~2 and 7.5×105planhts/hm~2 respectively.There were only 3 pieces difference in late sowing.No significant difference was found in accumulated temperature at the fastest leaf emergence among densities,the accumulated temperature requirement at the fastest leaf emergence was decreased with the sowing date delayed.The variation of accumulation temperature was not obvious when the inter plant growth rate was the fastest.With the increase of plant density,plant height showed a downward trend.The maximum and minimum of plant height difference was 24.5 and 16.5cm respectively under the condition of early sowing and late sowing.Plant height increased with the increase of nitrogen application,the change of the accumulated temperature of the fastest plant height increase was not obvious among different nitrogen treatments.Under the condition of early sowing and late sowing,the N0 and N450 of plant height difference was 58.5 and 25.4cm.3 The effect of different agronomic measures on dry matter accumulation.In early sowing treatment,the largest dry matter accumulation of population was 2458.7g/m~2,which harvest from 3×105planhts/hm~2.In late sowing treatment,dry matter accumulation of population increased with the density,7.5×105planhts/hm~2 density got the largest accumulation,up to 2172.9 g/m~2.Dry matter increased with the increase of nitrogen application.The population dry matter accumulation of N450 treatment was 3577.4 g/m~2 and 3666.3g/m~2 for the early and late sowing condition respectively.4 Effects of different agronomic measures on yield components and yield of rapeseedseedWith the increase of planting density,the number of single plant pods decreased.In the condition of the early sowing date,the highest yield is 4.5×105plant/hm~2.In the condition of the late sowing date,with the increase of density,the yield increased.With the nitrogen increasing,the number of single plant pods increased,the yield of early maturing rapeseed increased,But when the nitrogen fertilizer increased to 270kg/hm~2,the increase of rapeseed yield decreased.5 Effects of different agronomic measures on light energy and temperature production efficiency of rapeseedseedAmong the different densities,the light energy and temperature production efficiency of 4.5×105plant/hm~2 was the highest in early sowing;In late sowing date,the production efficiency of light energy and temperature increased with the increase of density.Under the condition of early sowing and late sowing,The production efficiency of Shengguang127 light energy are more than that Huayouza9 23.1% and 28.6%,and the production efficiency of temperature are more than that Huayouza9 16.0% and 29.7%.The light energy and temperature production efficiency of rapeseed increased with the increase of nitrogen application rate.When the amount of nitrogen is less than 450 kg/hm~2,light energy and temperature production efficiency of Shengguang 127 was significantly higher than that Huayouza9.Under the condition of early sowing and late sowing,the production efficiency of light energy increased by 23.1% and 18.2% respectively,and the increase of temperature production efficiency was 21.6% and 23.9% respectively.When the nitrogen amount reaches 450kg/hm~2,the production efficiency of light energy and temperature of Huayouza9 was higher than that Shengguang127.Under the condition of early sowing and late sowing,the production efficiency of light energy increased by 21.4% and 23.1% respectively,and the increase of temperature production efficiency was 16.8% and 21% respectively.According to the effects of different agronomic measures on individual development and yield of Shengguang 127,at the beginning of October sowing the density of /hm~2 is appropriate,the amount of nitrogen should be 270kg/hm~2.At the beginning of October sowing,the density of 3-4.5×105 /hm~2 was appropriate,and the amount of nitrogen was 270kg/hm~2;At the end of October sowing,the density of 6-7.5×105 /hm~2 was appropriate,and the amount of nitrogen was 270kg/hm~2.