Caryopsis Development and Anthocyanidin Accumulation of Colored Rice

The effects of environmental factors on accumulation of anthocyanidin during the development of caryopsis were studied with two colored rice cultivars,Xuenuo(japonica) and Aiganhuangbansuo(indica) as materials.The caryopsis growth and endosperm development of colored rice were basically the same as conventional rice,with the exception in its anthocyanidin accumulation in the pericarp.Anthocyanidin first accumulated in the pericarp close to awn(4-5 days after flowering),then to both sides and to dorsal vascular bundle,and last gradually expanded to the whole pericarp at 10 days after flowering.The accumulation of anthocyanidin mainly occurred at 7~20 days after flowering.Shading inhibited the accumulation of anthocyanidin,especially at early stage.High temperature went against the accumulation of anthocyanidin and relatively low temperature extended accumulation duration.