油菜种子休眠性对脂肪酸积累的影响及其分子机制

Effect of seed dormancy on lipid accumulation and its molecular mechanism in oilseed rape

油菜是我国最重要的油料作物之一,提高油菜籽产油量是油菜育种的重要方向。油菜籽休眠完善与否极大地影响了油菜籽最终的含油量。因此,对油菜种子休眠性与脂肪酸代谢的相关性进行研究十分重要。本文着重阐释了种子休眠的含义、分类及机制,从脂肪酸转运体、β氧化途径以及脂质转化过程等方面论述了种子休眠对种子油脂代谢的影响,分析了影响油菜籽含油量的因素,特别是在种子成熟过程中油脂消减对含油量的影响,最后,讨论了提高油菜种子含油量的一些思路以及待研究的科学问题。

Oilseed rape(Brassica napus L.)is one of the most widely grown oil crops and ranks the top-one edible oil in China.However,a significant proportion of the rapeseed oil in China relies on importation from abroad.In recent years,the planting area of oilseed rape in China continuously decreased and there was a paucity of cultivars which have wide adaption to adverse environment and resistance against a range of diseases.Above all,low seed oil content became a prominent problem.In order to improve rapeseed quality especially the seed oil content and change the passive situation of the country on international edible oil market,reinforcing the fundamental basic on the mechanism of seed oil formation seems necessary.In this review,we highlighted the influence of lipid decomposition during seed maturation on final seed oil content,and the phenomenon that seed oil rapidly decreases after reaching to a peak point about one week before harvest in rainy years.Some aspects,such as the metabolism of fatty acid in seeds,the acquisition of seed dormancy,and the association between post-peak seed oil decomposition and the acquisition of seed dormancy,were well illustrated to clarify the impact of seed dormancy on fatty acid accumulation.Finally,some constructive suggestions referring to the enhancement of rapeseed oil content in breeding practice were discussed.