Abstract:

The flower bud number and metabolism of Petunia hybrida‘Fantasy’under the condition of control（light strength 11.5 μmol ? m-2 ? s-1，day length 16 h），weak light（3.6 μmol ? m-2 ? s-1，16 h）and short day（11.5 μmol ? m-2 ? s-1，8 h）were observed and recorded. Observation on flower buds showed that the number of normal and total buds decreased dramatically while aborted buds increased significantly under either the weak light or short day stress. Metabolites were identified by mass spectra retrieval and spectra resolution combined with retention index. Then，we went on multivariate statistical analysis and determined semi-quantitatively by peak area normalization method. The results were as follows：we found out 111 peaks and 42 of them were identified. There was significant difference in metabolism of flower bud of Petunia hybrida‘Fantasy’under the condition of control，weak light and short day. Compared with control，the metabolic shifts was shown as the increasing of various amino acids and the decreasing of various sugars. And weak light had larger influence on metabolism of the flower bud than that of short day. Depletion of proteins and sugars was reckoned to be one of the reasons that lead to aborted flower bud under the weak light or short day stress.

Key words: Petunia hybrida, weak light, short day, flower bud, abortion, metabolomics