设施栽培中限根对油桃幼树叶片叶绿素含量、叶干重变化的影响

研究了设施栽培中限根对沪油018幼树叶片叶绿素含量、叶片干重的变化特点。结果表明:(1)限根幼树在秋季枝条停长后, 不同限根处理第1～8叶位叶片叶绿素含量均表现为“升—降—升”；相同叶位处理TR2各个叶位单位叶面积叶绿素含量均低于CK和TR1,CK仅在第1、8叶位较TR1高,而其它叶位均低于TR1。(2)测定盛花后19～262d树冠外围枝中部完全展开功能叶的叶绿素变化动态,结果不同限根处理Chla、总叶绿素含量与Chl(a/b)的变化均表现“降—升—降”的变化规律。限根对Chlb的季节变化进程的影响差异明显。(3)不同限根处理下比叶重的季节变化差异明显,但总的呈上升趋势。叶片干重含水量%的季节变化总的呈下降趋势,不同限根处理间的变化动态差异明显。

Effects of Root Confinement on the Chlorophyll Content and Leaf Dry Weight of Young Nectarine Tree Cultivated in greenhouse *

To explore the effects of root confinement on the chlorophyll content and leaf dry weight of young fruiting nectarine tree in greenhouse, tree were trained to central leaders and planted at in-row spacing of 1m with 1.5m between rows. When planting, different ways of root restriction were performed as: trees set in holes large enough to accommodate the root system(CK) and planting using nylon membranes(TR1) and using non-woven synthetic fabric(standard 0.5Kg/m2, thick 0.20mm)(TR2). The results showed that (1) in autumn chlorophyll (Chl) contents of different positioned leaves exhibited a common “up-down-up” temporal pattern in all trees treated by different root confinement. When different ways of root confinement compared, Chl contents per leaf area in TR2 were always lower than those of the same positioned leaves in TR1 and CK, but the Chl contents in TR1 were larger than all in CK except those of the 1st and 8th positioned leaves. (2)Chla and total Chl and the ratio of Chla to Chlb all presented a dynamic variation pattern of “down-up-down” during 19DAA (days after anthesis)～262DAA (actually Mar.29～Nov.28) in all root treatments, and it was revealed that the seasonal change of Chlb was obviously affected by different ways of root confinement. (3)The seasonal change of LWA (leaf weight area) during leaf development was very distinct among different root treatments, but all showed an ascending tendency. And the seasonal change of the content of dry weight presented a descending tendency in all treatments, but the temporal variation was distinct among different root treatments.