Expression Analysis Of BrCRTISO Gene And Antioxidant Capacity And Nitrate Content Study Of Orange-head Chinese Cabbage

Orange-head Chinese cabbage has a feature with orange inner leaves.Compared with ordinary Chinese cabbage,orange variety is rich in carotenoids which is good antioxidant and has important effect on human health.However,the accumulation mechanism of carotenoids and the nutritional characteristics of orange-head Chinese cabbage have not been known clearly.Based on the molecular markers,the linkage relationship between Br-or and the orange leaf is confirmed.With the real-time fluorescent quantitative PCR analysis,the expression of BrCRTISO is analyzed;Using Oxygen Radical Absorbance Capacity(ORAC)method,the total antioxidant capacity of orange-head Chinese cabbages is measured;By means of ultraviolet spectrophotometer,the nitrate content in Chinese cabbage leaf is determined.The results are as follows:1.The correctness of four molecular markers which had close linkage with Br-or was verified.The experimental data showed that the purpose gene and developed molecular markers(SSR9,InDell,InDel2)were closely linked.Through the study of the molecular marker identification in two groups of F2S5 population Q67 and Q448 and 43 orange-head Chinese cabbages,the marker crtiso was proved to be in accordance with orange head of Chinese cabbage lines,which suggested that this maker could be used as a functional marker for early identification of Chinese cabbage leaf color and BrCRTISO was likely to be the key controlling orange trait of Chinese cabbage.2.The expression of BrCRTISO gene was analyzed in six different Chinese cabbages with Actin as internal reference gene.The expression of BrCRTISO in head leaf of orange,yellow and ordinary Chinese cabbage(two varieties for each head color)showed that the expression of the gene in normal Chinese cabbage was higher than that in orange-head Chinese cabbage,which meant that the reason of the orange trait was likely to be the inhibited expression of the gene in cells of head leaf.3.Comparing the total antioxidant capacity in the orange-head and ordinary head of Chinese cabbages.Through the ORAC method,the total antioxidant capacity in different color heads of Chinese cabbage was analyzed.Also,the correlation between the antioxidant capacity and antioxidant substance was calculated.We learned that the total antioxidant capacity order was orange-head>y el low-head>ordinary-head of Chinese cabbage,and the antioxidant value was highly related to the carotenoids and total phenol content.4.There was lower nitrate content in orange-head Chinese cabbages.In the same cultivation condition,the nitrate content in head leaf of orange-head and yellow-head Chinese cabbages was relatively lower than the ordinary Chinese cabbage in the mature period.Therefore,it was more competitive in terms of food safety than the ordinary ones.