Effect of temperature on soluble protein and nucleic acid of leaves in Chinese Kale(Brassica alboglabra Bailey)

The effects of four different temperature such as T1(18℃ day/12℃ night),T2(24℃ day/18℃ night),T3(30℃ day/24℃ night),T4(36℃ day/30℃ night) treatments on soluble protein and nucleic acid were studied in Chinese Kale.The results showed that the content of soluble protein was the highest in 36℃ day/30℃ night treatment and the lowest in 30℃ day/24℃ night treatment.The contents of total nucleic acid,DNA and RNA in the stem apex decreased with prolongation of temperature.with prolongation of temperature treatment was prolonged,the contents of total nucleic acid and RNA in all treatments rose gradually after decreasing except for 36℃ day/30℃ night treatment which decreased continuously.The content of DNA showed a changing trend such as decreasing-increasing-decreasing except for 36℃ day/30℃ treatment which increased after decreasing.Low temperature could accelerated the synthesis of nucleic acid,maintained the stability of the nucleic acid,but high temperature inhibited the synthesis of the nucleic acid,DNA and RNA,and subsequently led to the decreasing of nucleic acid contents.