共查询到20条相似文献，搜索用时 214 毫秒
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在党的富民政策指导下,凡有自用地的庭院中都种植了各种果树,有的已开花结果,但有些果树虽开花不少,却座果极少。追其原因,除受自然条件影响外,其主要原因是只栽了一个品种的果树,有的虽然栽了两个品种的果树,但因花期不一致或两者间亲合力差,或选配的品种具有异花不亲合现象,座果率仍然很低。 相似文献
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矮化果树的栽培技术的发展对于水果产量的提高来说具有重要意义,因此,通过对矮化果树的栽培技术:矮化砧木栽培技术、矮化果树的嫁接技术、生长抑制剂的利用、矮化栽培技术的栽培方式的介绍,以期对矮化果树在北方的栽培技术有所启示。 相似文献
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对华北地区经济树种蚧虫的种类区系、发生和分布规律及为害特点进行了系统研究。据调查，现已知华北经济树种蚧虫共有９科１２２种。随纬度增高、立地条件恶化、植物群落简单、人为活动频繁、管理水平粗放，蚧虫种类增多，为害严重。一般情况下，观赏树木受害普遍，温室植物受害严重，果树及平原地区林木部分受害，山地森林受害轻微。 相似文献
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Hyphandria cunea is an insect that can damage hundreds of plants in its larval phase and needs to be placed under quarantine at an international level. Its hosts involve 600 plant species, including forest and fruit trees, shrubs, crops, vegetables, weeds and others. In 2006, we surveyed two Fraxinus chinensis Roxb stands, damaged to different degrees, after the invasion of H. cunea in the Changping district of the Beijing area. Given our survey of individual trees and investigation of bio-environmental factors, we pro-vide a preliminarily simulation of the growth situation of F. chinensis stands, damaged by H. cunea, by using the Forest Vegetation Simulator software （FVS）, which is supported by the ＂948＂ project from the State Forestry Administration of China. The results will provide a valuable reference in forecasting the effect of H. cunea and other invasive pests in China on forest ecological values. 相似文献
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梨叶枯病是在早酥梨上发现的一种新病害，病原菌为Ｍｙｃｏｖｅｌｌｏｓｉｅｌｌａ ｐｙｒｉｃｏｌａ。通过调查早酥梨叶枯病在田间的消长动态，实测不同病情指数下１年生早酥梨苗的高、粗生长量、７－８年生结果树平均单果重、单株产量，建立了苗期生长量和结果树产量损失估计模型，推算出该病害防治指标病指苗期为１２．７４％，结果树为１３．８４％。 相似文献
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We studied the influence of branch autonomy on the growth of reproductive and vegetative organs by establishing different patterns of fruit distribution within and between large branch units (scaffolds) in mature peach trees (Prunus persica (L.) Batsch cv. 'Elegant Lady'). Different patterns of fruit distribution were established by defruiting either whole scaffolds (uneven fruit distribution between scaffolds; US) or several selected hangers (small fruiting branches) per tree (uneven fruit distribution between hangers; UH). The effects of these patterns were compared with the effects of an even fruit distribution treatment (EVEN) in which fruits were thinned to achieve maximum uniformity of fruit distribution within the canopy. The desired fruit loads were obtained by differentially thinning the remaining bearing parts. On a tree basis, the response of mean fruit mass to fruit load was strongly affected by fruit distribution. The steepest mean fruit mass to fruit load relationship was found in US trees, whereas the relationship in UH trees was intermediate between the US and EVEN trees. On a scaffold basis, differences in fruit size between EVEN and US trees with similar fruit loads, though statistically significant, were relatively small, indicating that scaffolds were almost totally autonomous with respect to dry matter partitioning to fruit during the final stage of peach fruit growth. Hangers also appeared to exhibit significant autonomy with respect to the distribution of dry matter during the final phase of fruit growth. Branch autonomy was evident in scaffold growth: defruited scaffolds in the US treatment grew more than fruited scaffolds, and fruit distribution treatments had little impact on scaffold cross-sectional area on a tree basis. On the other hand, as observed for fruit growth, branch autonomy did not appear to be complete because the fruited scaffolds grew more in US trees than in EVEN trees under heavy cropping conditions. However, the effect of fruit distribution occurred only over short distances, and was negligible on organs located farther away from the source of heterogeneity (fruits), such as the trunk and roots. 相似文献
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为合理开发和有效利用观果树木资源,丰富城市园林绿化树种,提高城市景观和生态综合效益,采用查阅相关文献和实地考察相结合方法,调查研究了广州市观果树木资源现状及其在城市园林绿化中的应用效果。结果表明,广州城区观果树木种类丰富,共36科60属123种,主要应用在城市主干道路、主体公园和住宅小区。目前观果树木的应用已取得了良好的社会、生态、经济和景观效应。建议广州市在今后城市园林规划中,充分利用现有观果树木种类并根据区域特色适度引进新品种;在大力推广观果树木景观应用的同时,应加强市民文明行为养成教育。 相似文献
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通过对甘肃小陇山林区野生果树资源的调查研究,结果表明有199种(包括变种、变型),隶属于29科、58属,其中50.2%集中于蔷薇科和葡萄科。本文对127种具有重要经济价值的野生果树资源的分布、用途、利用现状进行了研究(表2).并提出了保护和可持续利用野生果树资源的建议。 相似文献
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甘肃野生果树资源及其开发利用策略 总被引：6，自引：2，他引：6
通过对甘肃各主要林区、保护区野生果树种质资源的初步调查,研究表明:甘肃野生果树资源丰富,有312种和46变种(变型),隶属于32科、70属。这些野生果树主要集中在蔷薇科、虎耳草科、小檗科、猕猴桃科、葡萄科、胡颓子科。首次对甘肃不同地理分布区域野生果树资源的丰富性进行了研究,结果表明:甘肃野生果树在各地理区域间分布不均衡,陇南最丰富,陇东南、陇西南较丰富,河西走廊最贫乏,陇中和祁连山较贫乏。同时提出了开发利用策略。 相似文献