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<正>核桃树的修剪要根据生长、结果的需要,改善光照条件、调节营养分配、枝组转化、促进或控制枝条的生长。修剪应根据枝条特性,选择合适的修剪时期,尽量避开伤流期,否则会因伤口产生伤流而造成养分和水分的大量流失,严重消弱树势,影响树体的正常生长发育。1核桃枝条的特性1.1伤流伤流是核桃枝条的特殊性质,每年有两个高峰期:一是落叶入冬后,随着气温降低伤流量增大,到大寒后逐渐降低,萌芽前基本停止;二是萌芽后随 相似文献
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1 整形修剪时期与方法
1．1修剪时期
核桃树修剪时期不当时会引起严重伤流，使养分流失，造成树势衰弱，甚至枝条枯死。据观察，伤流一般于秋季落叶后11月中旬开始到翌年萌芽后为止，伤流期有两个高峰，分别出现在落叶后的11月19日和萌发前的3月25日， 相似文献
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核桃树的修剪一般不宜在休眠期 ,因为休眠期修剪易发生伤流而削弱树势 ,甚至造成局部枝条枯死。根据生产中的实际经验 ,核桃树的适宜修剪期 ,以果实采收后至落叶前的时间较好。多年来我地在秋季修剪后 ,翌年春天核桃树叶肥大 ,色泽浓绿 ,还能促进坐果率的提高。1 初结果树的修剪 核桃树自开始结果到大量结果 ,其树体营养生长较旺 ,树冠逐年显著扩大 ,结果数量逐年增多 ,这时修剪 ,除要继续增减各级骨干枝外 ,还要注意保留辅养枝 ,疏去无用密挤枝、徒长枝和细弱枝。使各类枝条分布均匀 ,树冠内膛要适当多留结果枝 ,并要保持稀密适度以加大… 相似文献
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1适时整形修剪核桃具有休眠期修剪易出现伤流的特性，通常修剪时期宜选择在果实采收后至落叶前进行。但是过早修剪，不利于树体营养积累，在落叶前越晚越好。在发芽前15～20d进行修剪，效果也很好，这时伤流不太严重，对树体影响不大。 相似文献
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1 修剪时期 核桃修剪在休眠期不能进行 ,这是因为核桃在休眠期有伤流现象 ,如在此时期修剪 ,会严重影响树体正常生长与结果 ,所以修剪时应避开伤流期 ,宜在春季萌芽展叶以后或秋季落叶以前进行。2 早实核桃修剪技术 早实核桃一般 2～ 3年开始结果 ,分枝能力强 ,易抽生二次枝和徒长枝。在修剪时除注意培育好主、侧枝外 ,应及时控制二次枝和利用徒长枝 ,疏除过密枝 ,处理好背下枝。2 1 控制二次枝 二次枝抽生晚 ,生长旺 ,组织不充实 ,在北方易失水抽条 ,过多时消耗养分多 ,不利于结果。 1)在未木质化时 ,在北方即 4月底 5月初 ,对过旺… 相似文献
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早实核桃栽后3～4年即可挂果,大大缩短了结果期,栽培价值高。甘肃省张家川县从1999年开始引进并大力推广早实核桃栽培,引进优良品种10个,建园面积达到387.3hm2,目前部分核桃园已进入结果期。笔者在几年的栽培实践中,经过观察对比,注意到早实核桃修剪技术与其他果树相比,特点明显,现加以总结。1整形修剪时期一般果树主要在休眠期进行,因为此时树体的营养损失和受到的伤害最小。核桃树由于根压很大,易在切口处渗出树液,造成“伤流”现象,使枝条转化积累的养分和水分大量损失,影响树体正常生长和结果。据观察,伤流一般从落叶后11月中旬开始发生… 相似文献
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Eight common tree species used for urban landscaping were examined in this study for the effect of branch pruning on the rate and extent of wound closure (occlusion) and internal discolouration in the stem. Rate of wound closure when branches were removed with stem or branch of origin (flush cut pruning) and cuts made away from the branch collar (natural target pruning) were compared on all species over a 3-year period. Understanding the effects of pruning will benefit urban foresters in tree selection and potentially prevent downstream challenges associated with mechanical injury. The findings for all eight species supported the recommended guidelines of retaining the branch collar during pruning which has shown to facilitate effective wound closure. The exposed wood diameter (exposed) for all species were significantly reduced after the second growing season for injuries derived through natural target pruning but for the same period, injuries derived through flush cut pruning, only six species showed significant reductions in exposed wood diameter. Two other species (Mimusops elengi and Lagerstroemia speciosa) were observed to have no further reduction in exposed wood following the first growing season. Both wound inducing techniques (flush cut pruning and natural target pruning) resulted in no significant change in healing tissue production following the second growing season. Correlation analysis showed a strong positive relationship (r = 0.8–0.9) between the width of the wound and the length of discolouration in the stem, suggesting that smaller cuts were better suited to avoid extensive wound induced discolouration. This finding was further reinforced through visual observations of numerous pruning wounds of all eight species which showed that smaller cuts were better able to close over as opposed to larger wounds. 相似文献
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为探明早实核桃枝条更新对果实抗病性的影响,以6年生“绿岭”核桃树为试材,调查了“绿岭”核桃短期更新(更新枝枝龄为2~3年)和常规更新(更新枝枝龄为3~4年)的核桃果实发病情况。结果表明:果实发病初期,短期更新树和常规更新树的好果率无显著差异,果实抗病指数分别为5.58、3.61,表现为短期更新树显著高于常规更新树;果实成熟期,短期更新树的果实发病率、病情指数分别为64.07%、41.08,均极显著低于常规更新树的84.54%、59.95,短期更新树的抗病指数为2.49,极显著高于常规更新树的1.70;从发病初期到果实成熟期,短期更新树的好果率降低了34.93%,极显著低于常规更新树的43.05%,病情指数增加了22.20,显著低于常规更新树的31.35。由此可知,短期更新树果实病情恶化速度显著慢于常规更新树。总之,短期更新可显著提高“绿岭”核桃果实抗病性,且对延缓果实病情发展有显著效果。 相似文献
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Watersprout occurrence and growth were investigated over a two-year period in an early maturing peach cultivar (Alexandra) under different intensities of dormant pruning for fruited and defruited trees. A preliminary study focused on identifying the laws that determine the probability of presence and occurrence of watersprouts in relation to watersprout-bearing shoot (WBS) length. The increase in watersprout probability of presence and occurrence resulting from greater WBS length illustrated the high capacity of peach for sprouting. Watersprout lengths were measured, as well as the lengths of young shoots, one-year-old fruit-bearing shoots (FBSs) and older branches considered as WBS in order to evaluate total shoot growth within the tree. Watersprout number and total length tended to be higher under severe dormant pruning and in fruited trees than under light dormant pruning and in defruited trees. This stimulation of watersprout length appeared to compensate for the concomitant lower total length of young shoots, resulting in a constant overall vegetative growth rate for the whole tree. In the second year of the experiment, watersprouts were either removed by summer pruning or not in order to evaluate watersprout incidence on the rest of the tree. After light and severe watersprout removal (WSR), the annual diametrical growth of FBS tended to be higher and lower, respectively, compared to trees not submitted to summer pruning. Light WSR might favour light interception in the centre of the canopy, thus improving assimilate production and allocation to FBS, whereas severe WSR could prevent carbohydrate export from watersprouts to FBS. Under our conditions, the limit at which WSR intensity became detrimental for FBS diametrical growth appeared to be after approximately 75% of the watersprouts were removed. Severe WSR appeared likely to improve fruit diameter, whereas it had no significant impact on the percentage of soluble solids. 相似文献
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《Urban Forestry & Urban Greening》2002,1(2):75-82
Trees in urban areas are pruned for several reasons. Each pruning cut causes a wound, which leads at least in the exposed wood at the wound surface to discoloration and decay. The extension of the resulting defect depends on wound diameter, tree species, time of wounding, wound treatment, and last but not least the attachment of the branch to the stem. The effects of different pruning cuts on urban trees has been investigated in Hamburg, Germany, since 1985. The study of 750 different pruning wounds on typical urban tree species lead to the Hamburg Tree Pruning System (Hamburger Schnittmethode). The system is described in this paper and answers the following questions: How should branches with and without a branch collar be removed? How should dead branches be removed? How should branches with included bark or codominant stems be removed? What are the differences between tree species in wound response? What is the maximum wound size which will be effectively compartmentalised by the tree? 相似文献
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以6年生‘绿岭’核桃树为试材,调查了‘绿岭’核桃短期更新处理(枝条更新周期为2～3年)和常规更新处理(枝条更新周期为3～4年)的坚果品质及产量,研究了早实核桃枝条更新对坚果品质及产量的影响,以期为早实核桃更新提供科学依据。结果表明:短期更新处理的坚果三径、单果质量、出仁率均大于常规更新处理,其中出仁率差值可达2.45个百分点,存在极显著差异。短期更新处理的好果与轻病果的蛋白质含量分别为20.64%和19.73%,均显著高于常规更新处理,2种处理间核仁脂肪含量无显著差异。短期更新处理的单株产量为2.54 kg,比常规更新处理高出28%,且好果产量占比为69.18%,比常规更新处理高出14.48%。说明短期更新处理可以显著提高坚果的外观品质及蛋白质含量,在提高单株坚果产量方面效果显著,且可极显著提高好果的产量占比。 相似文献
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苹果幼树秋季^14C同化物贮藏及再利用 总被引：9，自引：4，他引：5
本试验研究了苹果幼树不同形态~(14)C同化物的贮备特点、季节变化及再利用特性。结果表明,1.苹果碳素同化物贮藏形式有淀粉、糖、氨基酸和有机酸。淀粉秋季先在根中积累,贮备前期(9月)达到高峰,枝干木质部于休眠前(12月)、韧皮部于萌芽前分别达到高峰;糖和有机酸落叶前枝干中较多、休眠期以根系贮藏为主;氨基酸仲秋(9月)开始在根中积累、而不再上运;落叶回流氮化物主要贮藏在枝干中。2.萌芽展叶主要利用枝干贮藏营养,早春新根生长为根系贮藏营养第一个分配中心,枝叶旺盛生长为其第二分配中心。3.根系贮藏碳素营养春季极少以糖形式直接供应地上部,首先在根中转化成氨基酸,经木质部上运并在其中脱氨形成有机酸,大部分用于能量消耗,一部分再生成糖供新器官结构建造。 相似文献
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试验比较了盛果期灰枣树对不同修剪方法的反应。结果表明,枣树连年修剪,根的数量、冠幅、干周均大于(牙刂)枣处理树。萌发枣头的数量、质量和抽生有效枣拐的数量等也表现出相似的结果。修剪树有效枣股数多于(牙刂)枣树,差异显著;百果鲜重较(牙刂)枣处理多40.1g,单株产量提高15.3%。叶片总糖和全氮测定结果:修剪处理在6月下旬含量较高,此时正值枣吊、枣头生长,花芽分化,开花和幼果发育的关键时期,这对树体的生长发育和产量提高都起到良好的作用;其次,修剪与环切结合的效果优于修剪+(牙刂)枣,但次于修剪处理。 相似文献