7个橡胶树品系树皮结构与农艺性状相关性研究

以我国自主选育的热试662、热试419等7个开割无性系为试材,采用石蜡切片技术,观测树皮乳管列数目、厚度等乳管分化特征参数,分析上述参数与胶乳产量、茎围等主要农艺性状的相关性。结果如下:1)7个品系中,石细胞以内的次生韧皮部厚度与茎围,再生皮的厚度呈正相关。2)胶乳产量与石细胞以内的次生乳管列数目,树皮中的次生乳管列数目与树皮总厚度的比值呈正相关;其中,热试419树皮结构的次生乳管列数目与树皮结构的总厚度的比值明显高于其他品系,次生乳管的总列数最多,乳管分化能力较强,且胶乳产量最高。3)热试9359和RRIM600次生乳管的分化能力较强,产胶潜力大。该实验结果为以树皮乳管分化指标辅助评价主要农艺性状提供了参考,也为参试品系割胶技术的开发提供了依据。     

湖北黄袍林场喜树木本资源及应用

喜树是我国特有的珍贵树种,其次生代谢物因含有一种重要生物碱而闻名。为了宣传这种珍贵喜树资源及推广应用,以湖北国营通城县黄袍林场为对象,简要介绍了黄袍林场喜树的木本资源生长特征、种子园、育苗及推广应用情况。希望引起政府部门和科研人员的重视和研究,提高对这种国家Ⅱ级保护植物的保护及推广应用。     

丛枝菌根真菌提高林木抗逆性机制研究进展

丛枝菌根（AM）真菌是存在于土壤中的重要真菌之一,它能够与宿主林木根系产生互利共生体,从而对林木的生长发育有着多种促进作用。文中综述了近10年来国内外关于AM真菌对林木影响的研究进展,包括AM真菌对林木的抗旱性、抗病性、抗盐性、耐热性、耐虫性及对有害重金属抗性的影响等,通过促进林木光合作用、营养吸收、新陈代谢等来增加林木生长量、生物量的积累,从而提高林木的抗逆性;对在AM真菌研究中存在的难题进行了分析,并对其在林木中的应用研究进行了展望,旨在为林木抗逆性机制研究、森林经营等提供科学参考。     

Direct quantitative real‐time PCR assay for detection of the emerging pathogen Neonectria neomacrospora

The epidemic outbreak in northern Europe of Neonectria neomacrospora, the causal agent of dieback in Abies spp., led the European and Mediterranean Plant Protection Organization (EPPO) to include the pathogen on its alert list in 2017. Effective monitoring of this pathogen calls for a rapid and sensitive method of identification and quantification. A probe‐based real‐time PCR (qPCR) assay based on the β‐tubulin gene was developed for the detection and quantification of N. neomacrospora in infected wood samples, and directly for ascospores. This study presents the first published species–specific molecular detection assay for N. neomacrospora. The analytical specificity was validated on taxonomically closely related fungal species as well as on 18 fungal species associated with the host (Abies sp.). The analytical sensitivity was tested on naturally infected wood, on purified pathogen DNA in a matrix of host DNA and on N. neomacrospora ascospores for detection of airborne inoculum. The latter was tested both with a DNA extraction step prior to qPCR and without DNA extraction by direct qPCR on collected ascospores. The assay was specific to N. neomacrospora, with a sensitivity of 130 fg purified DNA, or 10 ascospores by direct qPCR. Omitting DNA extraction and amplifying directly on unpurified ascospores improved assay sensitivity significantly.     

Susceptibility of Eucalyptus grandis and Acacia mearnsii seedlings to five Phytophthora species common in South African plantations

Eucalyptus grandis and its hybrids, as well as Acacia mearnsii, are important non‐native trees commonly propagated for forestry purposes in South Africa. In this study, we conducted pathogenicity trials to assess the relative importance of five commonly isolated Phytophthora spp. (Phytophthora alticola, P. cinnamomi, P. frigida, P. multivora and P. nicotianae) from the plantation environment on E. grandis and A. mearnsii seedlings. Overall E. grandis was more susceptible to the tested Phytophthora spp. than A. mearnsii. Phytophthora cinnamomi was the only pathogen that had a significant negative effect on both the host tree species, leading to a reduction in root and shoot weight as well as to death in the case of E. grandis. Phytophthora alticola and P. nicotianae exclusively affected E. grandis and A. mearnsii, respectively. This study updated the current knowledge on the pathogenicity of Phytophthora spp. on two important non‐native commercially propagated tree species from South Africa.     

珍贵树种林下套种广东紫珠的密度效应研究

为了评价珍贵树种人工林下不同套种密度对广东紫珠 Callicarpa kwangtungensis 生长的影响, 于 7 a 生降香黄檀 Dalbergia odorifera- 檀香 Santalum album 混交林下设置 3 个密度处理种植广东紫珠,即 在行间套种 1 行、2 行、3 行,株距为 0.8 m,分别于定植后 6、12 和 18 个月调查其地径、树高和生物 量。结果表明：3 个套种密度处理间广东紫珠地径差异不显著 (P ≥ 0.05),而高生长在各时间段均差异显 著 (P ＜ 0.05),单株生物量差异极显著 (P ＜ 0.01),表现出随密度增加而升高的趋势。本研究筛选出降香 黄檀 - 檀香混交林下套种广东紫珠的适宜密度为行间栽种 3 行 (12 500 株 · hm-2),6 个月收获 1 次,每年 可采收广东紫珠 1 479.08 kg · hm-2( 鲜重 ),收入可达 5 916.33 元 · hm-2,可显著增加林农短期收益,为珍 贵树种规模发展提供了一种实用可行的经营模式。     

Crown development in young Picea abies stands

A dynamic model of branch length and weight growth was developed for two contrasting sites, both with young stands of spruce. At one site sample trees were obtained from both unfertilised plots and from plots with increased growth rate maintained by annual fertilisation. At the second site unfertilised trees and trees subject to single applications of fertiliser were modelled. A model of the same structure was developed for each site and tested by application at the alternate site. In view of the close agreement between sites, model parameters were calculated based on all data combined. The model is driven by height increment and branch age. The sample trees were mostly open grown so that only a tentative estimate of the effects of between tree competition is given. The limitations of the model are stressed.     

The tree tenure factor in agroforestry with particular reference to Africa

Rights over trees are often distinct from rights over land. Tree tenure consists of a bundle of rights over trees and their produce which may be held by different people at different times. These rights include the right to own or inherit trees, the right to plant trees, the right to use trees and tree products, the right to dispose of trees and the right to exclude others from the use of trees and tree products. Factors affecting who had rights include the nature of the tree, the nature of the use and the nature of the person or group. Landowners and tree plants tend to be relatively advantaged in terms of their rights to trees. Those with temporary claims to the land and, in some case, women, tend to be disadvantaged. The implications of tree tenure issues for the design of agroforestry projects are discussed.

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Resumen Los derechos sobre los arboles muchas veces son distintos a los derechos sobre la tierra. La propiedad del arbol consiste en un lote o derechos sobre arboles y sus productos que pueden ser mantenidos por distintas personas en distintos tiempos. Estos derechos incluyen el derecho a poseer o heredar arboles, el derecho a plantar arboles, el derecho a usar arboles y los productos arboreos, el derecho a disponer de los arboles y el derecho a excluir a otros del uso de los arboles y los productos arboreos. Se incluyen en los factores que afectan quienes tienen determinados derechos la naturaleza de los arboles, la naturaleza de su uso y la naturaleza dela persona o grupo. Terratenientes y plantadores de arboles tienden a tener ventajas en terminos de sus derechos sobre los arboles. Aquellos con derechos temporales y en algunos casos las mujeres tienden a estar en desventaja. Aqui se discute la problematica de las implicancias de la tenencia de los arboles para el diseno de proyectos silvo-agropecuarios.

     

湖北发展乌桕生物质能源产业大有可为

笔者在调研的基础上,分析了乌桕作为生物质能源树种发展的优势,提出了湖北发展以乌桕作为生物质能源树种,前景非常广阔,供同仁参考。     

林木无性繁殖及其在林业生产中的应用进展

在对无性繁殖的特点进行总结的基础上，综述了无性繁殖在无性系林业、林木遗传改良、林木复幼等方面应用的最新进展。