Popis: |
Three types of mango inflorescence, viz. healthy (H), naturally malformed (N) and morphactin-induced malformed (M), of ‘Dashehari’, ‘Mallika’, ‘Benazir’ and ‘Taimuria’ cultivars were studied. Morphactin (500 mg 1−1) treatment drastically reduced the growth as well as the fresh weight of the panicles. IAA oxidase activity was significantly different in the 3 types of panicle, and ranged from 6.5 μmoles IAA/g tissue/h in ‘Taimuria’ to 39.4 in ‘Benazir’ for H, while it was from 25.5 in ‘Taimuria’ to 51.0 in ‘Mallika’ for N. However, for M it was more than double that for H. Catalase activity was the lowest for M followed by N and then H. Amylase activity did not exhibit any definite trend. The IAA oxidase had a significant negative correlation with catalase and growth parameters. The increase in the activity of IAA oxidase by morphactin treatment, which caused malformation-like symptoms, and the observed high activity of the enzyme in naturally malformed panicles suggest that malformation might be due to decreased levels of auxins or to hormonal imbalance. |