不同抗性烟草品系 Rubisco 及其活化酶对赤星病胁迫的 响应.

Using resistant and susceptible tobacco strains JYH and CBH as test materials, the effects of brown spot stress on the photosynthesis and activities of ribulose-1,5-bisphosphate carboxylase/oxygenase（Rubisco）and ribulose-1,5-diphosphate carboxylase/oxygenase activase（RCA）and their gene expressions were analyzed. The results showed that, there were obvious inhibition effects on a series of photosynthetic parameters and the activities, expression levels and protein contents of Rubisco and RCA in JYH at 9 d of brown spot stress. Meanwhile, tobacco brown spot stress notably reduced the photosynthesis and activities of Rubisco and RCA in CBH, in addition, the relative expression of Rubisco large and small subunits genes（rbcL and rbcS）and RCA genes（rca）and their protein contents all decreased under stress condition. In comparison with CBH, the activities, expression levels and protein contents of Rubisco and RCA in JYH were all significantly higher at the stress treatment of tobacco brown spot. The correlation analysis results also indicated that Pn had significant and extremely significant positive correlation with the activities, gene expression of Rubisco and RCA, respectively. These results suggest that the resistant strain JYH can maintain higher values of Pn, Rubisco and RCA activities under tobacco brown spot stress, which account for the resistance to brown spot stress. [ABSTRACT FROM AUTHOR]