[Objective] This study aimed to investigate the endodormancy release in nectarine bud treated by short-term freezing. [Method] Through short-term freezing at seven different temperatures for three different periods on...[Objective] This study aimed to investigate the endodormancy release in nectarine bud treated by short-term freezing. [Method] Through short-term freezing at seven different temperatures for three different periods on bud, the livability, burst, ratio of free water to bound water and membrane permeability of ＇Shuguang＇ nec- tarine bud were studied. [Result] On November 10, compared with non-freezing treatment （CK）, the bud burst, ratio of free water to bound water and membrane permeability treated by freezing at -5 and -8 ℃ were almost the same as CK. But the rest freezing treatments advanced the date of endodormancy release, while the bud burst, ratio of free water to bound water and membrane permeability were high- er than CK. on November 20 and 30, the effects of the freezing treatment on en- dodormancy release were the same when the treatment on November 10, and the effect was better as the treatment was later. [Conclusion] The correlation of the rate of bud burst, ratio of free water to bound water, and membrane permeability of the different freezing treatments indicated that the change from bound water to free wa- ter and the increase of membrane permeability were probably the signal of endodor- mancy release.展开更多
Plasma membrane （PM） Ca2+-ATPase activity in poplar apical bud meristematic cells during short-day （SD）-induced dormancy development was examined by a cerium precipitation EM-cytochemical method. Ca2+-ATPase activ...Plasma membrane （PM） Ca2+-ATPase activity in poplar apical bud meristematic cells during short-day （SD）-induced dormancy development was examined by a cerium precipitation EM-cytochemical method. Ca2+-ATPase activity, indicated by the status of cerium phosphate precipitated grains, was localized mainly on the interior face （cytoplasmic side） of the PM when plants were grown under long days and reached a deep dormancy. A few reaction products were also observed on the nuclear envelope.When plant buds were developing dormancy after 28 to 42 d of SD exposure, almost no reaction products were present on the interior face of the PM. In contrast, a large number of cerium phosphate precipitated grains were distributed on the exterior face of the PM. After 70 d of SD exposure, when buds had developed a deep dormancy, the reaction products of Ca2+-ATPase activity again appeared on the interior face of the PM. The results seemed suggesting that two kinds of Ca2+-ATPases may be present on the PM during the SD-induced dormancy in poplar.One is the Ca2+-punlping ATPase, which is located on the interior face of the PM, for maintaining and restoring the Ca2+homeostasis. The other might be an ecto-Ca2+-ATPase, which is located on the exterior face of the PM, for the exocytosis of cell wall materials as suggested by the fact of the cell wall thickening during the dormancy developlnent in poplar.展开更多
基金Supported by the Special Fund of Modern System of Agricultural Industry Technology(CARS-30-6)the Special Fund of Department of Science and Technology,Liaoning Province(2011204001)~~
文摘[Objective] This study aimed to investigate the endodormancy release in nectarine bud treated by short-term freezing. [Method] Through short-term freezing at seven different temperatures for three different periods on bud, the livability, burst, ratio of free water to bound water and membrane permeability of ＇Shuguang＇ nec- tarine bud were studied. [Result] On November 10, compared with non-freezing treatment （CK）, the bud burst, ratio of free water to bound water and membrane permeability treated by freezing at -5 and -8 ℃ were almost the same as CK. But the rest freezing treatments advanced the date of endodormancy release, while the bud burst, ratio of free water to bound water and membrane permeability were high- er than CK. on November 20 and 30, the effects of the freezing treatment on en- dodormancy release were the same when the treatment on November 10, and the effect was better as the treatment was later. [Conclusion] The correlation of the rate of bud burst, ratio of free water to bound water, and membrane permeability of the different freezing treatments indicated that the change from bound water to free wa- ter and the increase of membrane permeability were probably the signal of endodor- mancy release.
文摘Plasma membrane （PM） Ca2+-ATPase activity in poplar apical bud meristematic cells during short-day （SD）-induced dormancy development was examined by a cerium precipitation EM-cytochemical method. Ca2+-ATPase activity, indicated by the status of cerium phosphate precipitated grains, was localized mainly on the interior face （cytoplasmic side） of the PM when plants were grown under long days and reached a deep dormancy. A few reaction products were also observed on the nuclear envelope.When plant buds were developing dormancy after 28 to 42 d of SD exposure, almost no reaction products were present on the interior face of the PM. In contrast, a large number of cerium phosphate precipitated grains were distributed on the exterior face of the PM. After 70 d of SD exposure, when buds had developed a deep dormancy, the reaction products of Ca2+-ATPase activity again appeared on the interior face of the PM. The results seemed suggesting that two kinds of Ca2+-ATPases may be present on the PM during the SD-induced dormancy in poplar.One is the Ca2+-punlping ATPase, which is located on the interior face of the PM, for maintaining and restoring the Ca2+homeostasis. The other might be an ecto-Ca2+-ATPase, which is located on the exterior face of the PM, for the exocytosis of cell wall materials as suggested by the fact of the cell wall thickening during the dormancy developlnent in poplar.
