不同播期、密度、施N量对山地菜苔油菜农艺性状和产量效益的影响OA

In order to comprehensively evaluate and recommend the optimal treatment combination of sowing date,planting density and fertilizer amount for mountain vegetable rapeseed in high altitude mountainous areas,stepwise regression and grey correlation analysis methods was used,the agronomic traits and yield benefits of mountain vegetable rapeseed with 9 cultivation factor combinations at the same altitude in Yuxi from 2019 to 2021 were compared and analyzed.The results showed that,(1)with the delay of sowing date,plant height,fresh forage weight per plant,fresh moss weight per plant and harvested fresh moss weight showed a downward trend,and prolonging growth period,increasing fresh biomass per plant and fresh moss yield per plant were beneficial to the increase of moss yield;(2)the biological yield of fresh forage was different in different years among 9 combined treatments;(3)the correlation degree between the yield of rapeseed and the main agronomic factors of different combined treatments was very different;(4)there were different degrees of differences in the yields of the 9 treatment combinations in different years,and the yields of the 3 levels of sowing date and density were extremely significant and significant differences,respectively,while there was no significant difference between the 3 levels of N application amount;(5)the output value of mountain vegetable rapeseed varied to different degrees due to different treatment combinations,and the output value showed a sharp decline trend with the delay of sowing date.It was recommended that the optimal combination of sowing date,planting density and N amount of mountain vegetable rapeseed in high altitude mountainous area was sowing date on October 20+planting density of 7.5×104-10.5×104 plants/hm2+5 leaf stage N amount of 172.5-207.0 kg/hm2.