Physiological differences between yellow-seeded and black-seeded rapeseed (Brassica napus L.) with different testa characteristics during artificial ageing.

摘要

Yellow-seeded rapeseed (Brassica napus L.) is a new kind of breeding resources with yellow color, increased oil and protein content and less unwanted crude fiber content of seed due to the thinner and transparent testa compared with traditional black or brown-seeded. To analyze the longevity of the yellow-seeded rapeseed in storage, we compared physiological differences of the yellow and black-seeded near-isogenic lines with artificial ageing. The yellow-seeded testa proportion decreased 20.1%, anthocyanin content increased 25.2% and melanin content decreased 80.4% in relation to black-seeded. After artificial ageing, compared with the black-seeded, the yellow-seeded showed faster deterioration with lower germination percentage, lower seed vigour index and lower reducing sugar, while electrical conductivity and malondialdehyde (MDA) content were significantly higher, the activities of antioxidant enzymes, peroxidase (POD), catalase (CAT) and superoxide dismutase (SOD) were significantly lower. The results suggest that the transparent testa the yellow-seeded rapeseed lacked some abilities to protect the embryo against adverse environmental conditions and lead to the poor storability, indicating that the pigments content of rapeseed testa maybe play a protective role against seed deterioration during artificial ageing..