黑米果皮花色素沉积过程的研究

Study on the Pigmentation of Anthocyanidin in Pericarp of Black Rice

以3个籼型黑米品种为材料，利用扫描仪对颖果进行即时扫描观察，对自然条件下和人工控制条件下，授粉后不同天数的颖果皮在发育过程中花色素的沉积进行研究。结果表明：黑米花色素只在颖果的果皮中合成和沉积，未观察到在种皮和糊粉层中沉积；果皮在授粉后3d开始沉积花色素，授粉后5～6d花色素迅速增加，7d后花色素充满整个颖果皮；颖果的远胚端最早沉积花色素，以后逐渐延伸到胚端并使整个果皮着色；果皮所有的部位都可独立合成和沉积花色素，未观察到花色素在果皮不同部位的细胞中运输；花色素的合成需要适宜的温度和充足的氧气，低温或缺氧不利于花色素的合成。

By real-scanning through a scanner, the pigmentation of anthocyanidin in pericarp was studied with three black indi- ca varieties during caryopsis development in different days after pollination under natural and artificial controlled conditions. The anthocyanidin of black rice caryopsis synthesizes and pigmentizes only in pericarp, and no anthocyandin was observed in endothelium and aleuronic layer. Anthocyanidin in pericarp begins to pigmentize 3 days after pollination, and increases rapidly 5-6 days after pollination, and the whole caryopsis pericarp is full of anthocyanidin 7 days after pollination. Anthocyanidin firstly pigmentizes at the part of caryopsis away from embryo, then gradually extends to the part near embryo and makes the whole pericarp pigmentized. Anthocyanidin can he independently synthesized and accumulated in all over the pericarp. No transportation of anthocyanidin was observed from cell to cell in different parts of pericarp. Anthocyanidin synthesis needs proper temperature and oxygen, which will fail at low temperature or deficient oxygen.