群体密度对冬油菜产量和经济性状的影响

研究了西北旱寒区大田条件下不同种植密度对冬油菜越冬率、产量及其构成因素、结角层结构、含油率等的影响。结果表明,群体密度在120万株/hm2~60万株/hm2,越冬率可达到80%以上。产量随种植密度增大而降低,60万株/hm2、90万株/hm2、120万株/hm2、150万株/hm2的产量分别为3 160.05 kg/hm2、3060.00 kg/hm2、2 860.05 kg/hm2、2 431.05 kg/hm2。随着密度的增加,分枝部位增高,单株总分枝数减少,其中二次分枝减少大于一次分枝,主花序长度减少,角长、千粒重、单株产量等均降低。含油率也随种植密度增大而降低,60万株/hm2、90万株/hm2、120万株/hm2、150万株/hm2的含油率分别为43.12%、41.91%、41.93、38.9%,以60万株/hm2含油率最高,达到43.12%。在西北旱寒区,冬油菜合理的群体密度为60万株/hm2~90万株/hm2。

Effects of Population Density on Yield and Economic Characteristics of Winter Rapeseed In Northwest Drought and Cold Region

In field condition,the effects of different planting density on the winter-survival,yields and its components,pod layer structure,oil content of winter rapeseed were studied.The results showed that the winter-survival was over 80% with the densities ranging from 600 000 plants/hm2 to 1 200 000 plants/hm2.The yield was decreased with the increase of population densities,it was 3 160.05 kg/hm2,3 060.00 kg/hm2,2 860.05 kg/hm2and 2 431.05 kg/ hm2,respectively from 600 000 plants/hm2,900 000 plants/hm2,1 200 000 plants/hm2 and 1 500 000 plants/hm2.As the population densities accelerated,the branch was high;number of branch per plant was dropped among which the second branch decresed faster than that of the first ones;and pod length,yield per plant,1000-seed weight were also down.The oil content was the same.The oil content under treatment of 600 000 plants/hm2 was the highest which was 43.12%.The other was 41.91%,41.93%,38.9% respectively.The suitable densities range were from 600 000 plants/hm2 to 900 000 plants/hm2 in northwest drought and cold region.