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1.
营林技术措施不仅可以促进林木速生丰产,而且是防治林木害虫的有效方法之一。通过营林技术措施能改变害虫发育繁殖的条件,抑制害虫的发生;可以改变林间昆虫和其它生物的种类及组成,使害虫的天敌增多;可以直接消灭害虫,大大减少其数量;可以提高林木抵抗能力,减轻其为害。它是“防重于治”的重要手段,是林木害虫综合防治工作中必不可少的内容。现就营林技术措施的主要方面,结合我省实际情况,举例说明它对防治林木害虫的作用。 一、选择抗虫树种或品种:近几年来在南京、溧阳、苏州等地发现的松干蚧是马尾松和赤松的毁灭性害虫,引起松树枯死.  相似文献   

2.
林木种子是林业生产中最基本的物质,林木种子质量好坏直接影响林木的成长发育,开展林木种子质量检验,并通过林木种子质量分析,确定种子使用价值,提高种子质量是林木种子经营中的一项重要工作。林木种子品质包括遗传品质和播种  相似文献   

3.
从分子水平上研究和调控林木生长发育是林木生物技术发展的新趋势,然而由于林木作为研究材料的局限性,如难以在实验室操作和较长的生长周期等,大大阻碍了林木分子生物学的研究.拟南芥是植物学研究中最重要的模式植物,是进行植物分子生物学研究的极好材料.近年来的研究表明,草本植物拟南芥不仅可以为林木分子育种提供基因资源,还可以作为林木分子生物学研究的辅助手段,甚至可以直接作为林木发育分子机理研究的实验模型.本文重点讨论拟南芥在研究林木材质形成、生殖生长和休眠等独特生理规律上的重要价值,在此基础上提出合理运用拟南芥模型,结合林木本身的特点,建立林木与拟南芥的联合研究体系,是开展林木分子生物学研究的重要思路.  相似文献   

4.
生长素信号转导途径对林木根系的影响   总被引:1,自引:1,他引:0  
植物体内信号分子———植物激素在调节植物各种生长发育进程中具有重要作用。生长素是调控植物根系发育唯一具有极性运输特性的激素,调控过程包括生长素生物合成、极性运输和信号转导。文中从生长素合成、代谢、运输、信号转导的主要途径和影响林木根系形成的相关基因及激素互作等方面进行了系统论述,提出了林木生长素信号转导途径研究的新思路,展望了林木根系形成机理研究及其对林木根系调控的应用前景。  相似文献   

5.
修枝作为一种传统的森林经营措施,在调节林分结构、调控林木生长、提高木材质量、维持林分稳定性等方面具有重要作用。探索科学合理的修枝技术是国内外林业科技工作者的研究热点。文中综合国内外的研究进展,从林内小气候、林下植被以及林地土壤3个方面阐述了林木的修枝效应,以期揭示林木修枝对环境的作用规律,为人工林修枝技术的研究与应用提供依据;同时指出当前我国林木修枝工作中存在的问题,并提出展望,以期为今后的研究和生产实践提供参考。  相似文献   

6.
真菌病害是林木的主要生物胁迫之一,严重影响林业生态安全和经济效益。近年来随着组学技术的突破,转录组技术和代谢组技术已成功应用于林木真菌病害研究,主要包括致病和抗病关键基因的挖掘、林木防御物质的动态合成、抗病分子育种等方面,但林木如何抵御真菌病害及其两者间的互作机制仍是今后研究的热点与难点。文中通过对林木遭受真菌侵染后的转录组信息和代谢组信息进行探讨,包括类黄酮物质合成途径、植物激素信号转导、林木防御关键基因和关键代谢物、关键防御机制及功能网络等,将在理论上丰富林木响应真菌病害侵染的过程,为林木和真菌病害的互作研究奠定基础,并为林木抗性育种和化学防治提供参考;此外,基于目前转录组和代谢组在林木真菌病害防御反应方面的研究,对林木基因组研究、多组学联合研究以及病原菌组学研究等进行展望,以期为林木真菌病害研究提供新思路。  相似文献   

7.
通过对传统林木遗传改良的成就进行概述,分析了基因组研究的发展对传统林木遗传育种的影响,基因组时代的林木遗传改良方法。研究结果表明,传统的林木遗传改良在提高林木生长量和抗性等选育方面取得了显著的成果,单一或者几个树种成为一个国家或地区的主要造林树种成为可能;基因组学的发展从基因的水平对认识林木的遗传本质提供了信息,也丰富了传统遗传改良的方法和手段,必将加速林木遗传育种的进程;基因组学只是辅助传统林木遗传育种的工具,不可能替代传统林木遗传改良理论、方法和技术。  相似文献   

8.
林木根系形态分布及其影响因素   总被引:16,自引:0,他引:16  
林木根系形态分布研究是森林生态系统研究的一部分。根据近20年国内对林木根系形态分布研究的成果综述了立地条件、林龄、混交方式、土壤类型等因子对林木形态分布的影响。并提出了林木根土相互关系需进一步研究的问题,认为林木根系数学模拟技术研究将是今后根系研究的一个重要方面。  相似文献   

9.
挖掘高固碳树种,选育高固碳林木良种是实现“双碳”目标,发挥林业在生态文明建设中重要作用的有效手段。为了梳理我国高固碳林木良种选育的进展,该文对高固碳树种的选择、高固碳林木良种选育研究现状、存在问题及建议等方面进行了总结,旨在为今后开展高固碳林木良种选育提供参考。  相似文献   

10.
杨树丰产林内培育平菇的技术研究   总被引:1,自引:0,他引:1  
该项研究,根据平菇与林木相反相成的关系,充分利用郁闭后的林地环境,培育出平菇并促进了林木生长。对林下培育平菇的技术重点研究了:①适生林下的平菇品种及其繁殖;②栽培基质;③栽培管理包括菌丝生长、子实体发育和越夏、防治病虫害、废料处理等;④鲜菇加工。结果是每亩杨树丰产林中产平菇26285公斤;林木生长量增加0.4914立方米。  相似文献   

11.
分子设计育种研究进展及其在林木育种中的应用   总被引:1,自引:0,他引:1  
阐述了分子设计育种的概念、研究进展及其在动植物遗传育种中的应用。结合当前林木育种发展现状和育种目标, 介绍了开展林木分子设计育种的研究基础, 包括林木多基因转化技术研究、林木的分子标记辅助选择研究以及林木的生物信息学研究。针对林木分子设计育种现状, 分析了开展林木分子设计育种存在的相关问题, 并对今后的应用前景进行了展望。  相似文献   

12.
营造速生丰产林的关键技术   总被引:4,自引:0,他引:4  
为建设高档次速生丰产林,作者借鉴国外经验,提出6项关键技术措施,即:建立树木栽培种、选育优良无性系、突破繁殖技术、改革育苗方法、严格立地选择和配套栽培措施。  相似文献   

13.
森林植物分子生态学的核心内容是检测其群落、种群、个体水平上的遗传多样性.较详细地综述了DNA水平上森林植物分子生态学的研究方法:DNA分子标记、DNA测序、基因克隆技术、DNA芯片技术的的原理和方法;简要介绍了蛋白质水平上的研究方法:等位酶分析和蛋白质组学的原理和方法.  相似文献   

14.
广东省林木良种现状及其发展对策   总被引:1,自引:0,他引:1  
文章概述了广东省林木良种现状和特点,分析其存在问题,并提出解决问题的对策和发展策略。  相似文献   

15.
陆江 《林业调查规划》2021,(2):153-156,164
以广西来宾灰木莲阔叶林、杉木针叶林分作为研究对象,分别以树冠竞争指数、Hegyi简单竞争指数作为因变量,3 a内胸径增长量作为自变量,研究林分内林木竞争对单木胸径生长量的影响。结果表明,林木胸径增长量与竞争指数均为负相关,表明林木受到的竞争越大,林木的胸径增长量就越小;作为阔叶树种的灰木莲胸径的增长量比针叶树杉木更容易受到林木树冠竞争的影响;相对于Hegyi简单竞争指数,树冠竞争指数更能说明林木胸径增长量与林木竞争程度的关系。  相似文献   

16.
Increasing incidences of drought-induced tree mortality are being recorded worldwide, including Africa. African forests cover a significant proportion of the continent, which implies that African forest sustainability is threatened from a climate-change perspective. This is especially problematic in a developing nation context, because forest ecosystems such as plantation forestry provide important goods and services that sustain human well-being and economic growth. Disentangling the likely triggers of tree mortality (including those linked to drought) in landscapes would not only explain the mechanisms underlying local die-offs, but also better predict future mortality events. Methods applied in the field of ecophysiology are particularly useful to study in situ plant responses to an environment. We consider the status quo of global peer-reviewed publication outputs during the past century that have made use of key ecophysiological research approaches, specifically studies concerning ‘tree xylem anatomy’, ‘tree xylem cavitation’, ‘tree leaf gas-exchange’ and ‘tree xylem hydraulic conductivity’. We highlight the growth and applicability of this research field in understanding tree ecology. We also assess the role that the forestry sector has had in promoting such research to ensure future-proof forest products. Most importantly, we consider how Africa with its vast forested landscapes fits within this research spectrum. The last decade saw an increase of up to 60% in the total number of articles published, particularly with a focus on tree xylem cavitation and conductivity. Although forest research contributed greatly to the global tally of ecophysiological studies, and such studies in Africa have also increased by up to 88% in the past decade, there remains a general lack of this research topic in the continent. It is clear an optimisation of applied ecophysiological concepts and techniques will promote an improved understanding of tree mortality patterns. We argue that ecophysiological data will be crucial to future-proof tree improvement strategies in African commodity production landscapes, especially given future drier climates.  相似文献   

17.
乔木树种体细胞胚胎发生的研究与应用   总被引:6,自引:0,他引:6       下载免费PDF全文
综述了乔木树种体细胞胚胎发生的研究现状,其中包括体细胞胚胎发生的基本步骤;影响乔木树种体细胞胚胎发生及其植株再生的因素。展望了乔木树种体细胞胚胎发生的应用前景及研究方向,提出了乔木树种体细胞胚胎发生在研究和应用过程中存在的问题。  相似文献   

18.
汕头中小水库水源林改造树种的选择及其模式配置   总被引:2,自引:1,他引:1  
以汕头市中小水库水源林为研究对象,全面踏查区域内水源林的阔叶树种种类和主要森林群落类型;选择该区域林分形成时间较长、群落特征明显、建群树种以阔叶树种为主的林分设立标准地进行调查,根据调查中出现的阔叶树种、主要群落类型的树种组成和结构功能、造林试验和有关文献资料推荐的适宜该区域造林的树种等综合因素,提出了台湾相思等18种中小水库水源林优化的适生树种;以现有森林群落的评价选优为基础,根据主要森林群落的结构、功能分析数据筛选了台湾相思林等5个林分优化配置模式。为特定区域的林分经营提供一套具有科学依据、实用价值高的技术应用方案。  相似文献   

19.
This article reviews the research and application of airborne laser scanning for forest inventory in Finland, Norway and Sweden. The first experiments with scanning lasers for forest inventory were conducted in 1991 using the FLASH system, a full-waveform experimental laser developed by the Swedish Defence Research Institute. In Finland at the same time, the HUTSCAT profiling radar provided experiences that inspired the following laser scanning research. Since 1995, data from commercially operated time-of-flight scanning lasers (e.g. TopEye, Optech ALTM and TopoSys) have been used. Especially in Norway, the main objective has been to develop methods that are directly suited for practical forest inventory at the stand level. Mean tree height, stand volume and basal area have been the most important forest mensurational parameters of interest. Laser data have been related to field training plot measurements using regression techniques, and these relationships have been used to predict corresponding properties in all forest stands in an area. Experiences from Finland, Norway and Sweden show that retrieval of stem volume and mean tree height on a stand level from laser scanner data performs as well as, or better than, photogrammetric methods, and better than other remote sensing methods. Laser scanning is, therefore, now beginning to be used operationally in large-area forest inventories. In Finland and Sweden, research has also been done into the identification of single trees and estimation of single-tree properties, such as tree position, tree height, crown width, stem diameter and tree species. In coniferous stands, up to 90% of the trees represented by stem volume have been correctly identified from canopy height models, and the tree height has been estimated with a root mean square error of around 0.6 m. It is significantly more difficult to identify suppressed trees than dominant trees. Spruce and pine have been discriminated on a single-tree level with 95% accuracy. The application of densely sampled laser scanner data to change detection, such as growth and cutting, has also been demonstrated.  相似文献   

20.
Major challenges exist for applied gene conservation of forest genetic resources in native habitats of the Mexican and Central American Pines, Pinus radiata and the Southern US pines. They include population decline and population structure changes, due to forest removal, conversion of forest land to other uses, fires, climate change, diseases and pests. However, tree breeders continue to struggle with methods that would meaningfully integrate tree breeding and conservation populations. In this review, I will start by outlining the importance of gene conservation in tree breeding programs, then highlight some challenges and opportunities for applied gene conservation programs; and lastly, I share results of a large body of applied research and other activities aimed at genetically characterising the base population of P. radiata in Australia and New Zealand, for the purposes of effective ex situ gene conservation. Main threats for species grown in exotic environments also include introduced diseases and pests, and more recently, climate change. Consequently, movement of genetic material is often restricted and genetic resources of pine species are not readily expanded by further importations from overseas. Therefore, conservation of genetic material currently in these countries is likely to be important for the long-term viability of plantation forestry using pine species. In addition to understanding the largely unpredictable or speculative biological and economic worth of rare alleles, the greatest challenge that we have in ex situ gene conservation is to develop practical approaches for infusing genes from base populations of unimproved material into more advanced-generation breeding programs without greatly affecting productivity gains. Other notable challenges include perceived costs and benefits of gene conservation in the face of increasing privatisation of forest estate. While financial resources for domestication of alternative species are declining, a vast number of existing species and provenance/progeny trials of P. radiata, the Mexican and Central American pines and the Southern US pines provide an excellent gene resource for the future.  相似文献   

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