葡萄萌芽期冬芽与枝蔓间水分联系再建立的动态观察

Observation of the rebuilding of water connection between grapevine compound bud and cane during bud break

在冬季休眠期葡萄冬芽与枝条间存在物质与水分运输的隔离,但进入到春季萌芽期,冬芽与枝蔓间又重新恢复了物质与水分的联系。冬芽与枝蔓/新梢间是以何种方式(细胞间扩散或木质部运输)进行水分联系,以及葡萄冬芽与枝蔓间水分联系的再建立的动态过程,还未见报道。本文以八年生酿酒葡萄品种‘霞多丽’为试验材料,观察研究了葡萄萌发过程中冬芽与枝蔓间水分联系再建立的动态过程。结果表明,在新梢生长期,冬芽与新梢间存在维管束联系,但在冬芽停止生长后,未见冬芽与枝蔓/新梢通过木质部进行水分联系,尤其是在冬季休眠期,冬芽含水量低于枝蔓含水量,且冬芽水分含水量保持在40%以下。进入春季后,伴随冬芽的膨大生长,冬芽与枝蔓间通过维管束进行水分联系重新建立,但在冬芽膨大初期(第I期),只见冬芽基部与枝蔓间有维管束相连,芽轴中上部未见维管束,但基部维管束并未发挥水分运输的功能,随着芽轴的延伸生长,维管束逐渐形成,尤其是进入到芽鳞展开期(第III期)后,可以见到水分通过维管束运输至芽内,这表明冬芽与枝蔓间水分联系建立与芽膨大生长及芽内维管束逐渐发育密切相关。

The latent buds of grapevine （Vitis vinifera） are isolated with the cane in water and nutrients trans-portation during dormant period in winter, but they rebuild connection of water and nutrients at the stage of bud break. It is not very clear about the ways of water transportation between cane and buds, including diffusion and xylem transportation, and we also know very little about how the connection is rebuilt during the stage of bud break. 8-year-old vines of cultivar ＇Chardonnay＇ were used as experimental materials, we observed the dy- namic changes in the process of water re-connection between cane and buds. The results showed that during growing season of grapevine, the compound buds kept water connection with shoot through xylem vessels, but when the bud got into dormancy stage, no water was observed in the xylem vessels of bud. In winter, the water contents of latent buds were stable and kept lower than 40%. With the latent buds started to expand in spring, the water re-connection between buds and cane was observed, and during stage I, xylem was observed at the base of buds, but no xylem was observed in the upper part of the buds at this stage. As the buds continued to expand, vascular bundle was formed gradually in bud axis. After stage III, water transportation through xylem vessels from cane to bud was observed, suggesting that the rebuilding of water connection between bud and cane had close relations with the growth and development of buds.