Abstract: Taking the floral buds of 10 years old field-cultivated and 3 years old potted nectarine (Prunus persica var. nectarine cv.Shuguang) as test materials, and by the method of real-time quantitative PCR, this paper studied the expressions of the AQPs genes δTIP1 and PIP1;1 during dormancy and dormancy-release (September 15, 2009-January 15, 2010) and the transcriptional levels of the genes under low temperature stress. Within the period of dormancy and dormancy-release, the transcriptional level of PIP1;1 presented a persistent increasing trend, and the high level expression of PIP1;1 in January could be related to the efflux of water through cytoplasma membrane and vacuolar membrane, which protected the bud cells from ice crystal injuries. The contents of soluble sugar, soluble protein, and proline in the bud cells all peaked in January, which prevented the excessive water loss from the cells. After 2 weeks of low temperature treatment, the PIP1;1 had a high level expression, indicating that it was a cold-induced gene. The transcriptional level of δTIP1 fluctuated during dormancy,and increased significantly during dormancy-release,which might be induced by the dormancy-release signals in buds and the resumption of plant activity.After 2 weeks of low temperature treatment, the expression level of δTIP1 had no increase, indicating that δTIP1 was not a cold-induced gene.

Key words: aquaporin, peach floral bud, dormancy, real-time quantitative PCR, cold inducement