油菜终花后角果和叶片光合对籽粒产量和品质的影响

Influence of Silique and Leaf Photosynthesis on Yield and Quality of Seed of Oilseed Rape (Brassica na pus L.) after Flowering

以‘秦优7号’油菜品种为材料,设置叶片和角果遮光及摘除叶片处理,通过田间试验测定分析终花后角果和叶片的光合特性及其对籽粒产量、含油量及脂肪酸组成的影响。结果显示:(1)终花后油菜角果遮光使籽粒的千粒重、产量、含油量分别显著降低54.7%、62.1%、44.2%,且籽粒中硫甙含量及脂肪酸中棕榈酸、硬脂酸含量显著升高,亚麻酸含量显著降低。(2)叶片遮光和摘除叶片分别显著降低角粒数11.7%、11.3%,降低籽粒千粒重22.5%、17.9%,单株产量分别降低35.3%、44.7%,使籽粒脂肪酸中亚油酸、亚麻酸等含量显著增加,但对籽粒含油量无显著影响。(3)终花后油菜绿色角果皮最大面积是绿叶面积的1.54倍,角果叶绿素a、b以及类胡萝卜素含量显著低于叶片,但角果的净光合速率、蒸腾速率显著高于叶片;且角果层的光辐射强度显著高于角果层下的叶片层;角果响应光辐射强度的光补偿点、光饱和点均显著高于叶片;即角果能够适应较高强度光辐射环境。研究发现,油菜结角期角果层接受大部分光辐射,角果的光合活性显著高于叶片,是主要的光合器官,角果光合状况对籽粒产量、含油量及脂肪酸组成有显著影响。

With oilseed rape（Brassica napus）hybrid the‘Qinyou No.7＇as material and plants of which after flowering were managed according treatments：shading leaf,shading silique and plucking leaf,such a field experiment was conducted to investigated photosynthesis characteristics and influence of the silique and leaf photosynthesis on seed yield,seed fatty acid content and seed fatty acid profile in this paper.The results showed that：（1）1000-seed weight,yield and fatty acid content of the seed declined by 54.7%,62.1%and 44.2%,respectively for the treatment shading silique,while contents of glucosinolate in the seed,as well as palmitic acid and octadecoic acid in fatty acid of the seed significantly increased and linolenic acid significantly decreased.（2）When leaves of the rape plant after flowering were shaded or plucked off,the seeds number per silique reduced by 11.7%,11.3%,and 1000-seed weight decreased by 22.5%,17.9%,respectively as so the seed yield per plant decreased by 35.3%,44.7%,while linolenic acid contents of seed fatty acid significantly increased and no notable influence on total contents of fatty acid in seed.（3）After flowering,green silique peel of the rape plant grew up to maximum area 1.54 double versus to area of green leaves,and solar radiation distribution a great quantity located in silique layer,where net photosynthetic rate.The transpiration rate of the silique were significantly high than that of the leaf,though contents of chlorophyll a,b and phytoxanthin in the silique were far lower.Actually the silique photosynthesis responding to photon flux density exhibited a higher light compensation point and higher light saturation point compared to the leaf.This infers that the silique is relatively endurable to stronger light radiation intensity in environment.Thus the study revealed that silique layer of oilseed rape accepted major light radiation during post-flowering stage and exhibited higher photosynthetic activity.The silique was main photosynthetic organ of rape plant and strongly influenced yield,fatty acid content as well as fatty acid profile of seed by photosynthesis.