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41.
J. Roux B. Eisenberg A. Kanzler A. Nel V. Coetzee E. Kietzka M. J. Wingfield 《New Forests》2007,33(2):109-123
Plantations of Pinus spp. constitute approximately 50% of the South African forestry industry. The first aim of this study was to develop a reliable
inoculation technique to screen Pinus spp., for tolerance to infection by F. circinatum, which threatens pine forestry in South Africa. Inoculation of branches was compared with stem inoculations and we considered
the number of branches or trees required to obtain statistically significant results. Furthermore, variation in the susceptibility
of some Pinus families, clones and hybrids was considered. Results showed that branch inoculations were closely correlated with those from
stem inoculations, and that it is important to consider branch and stem diameters when assessing susceptibility of trees.
Subsequent trials using branch inoculations showed significant differences in F. circinatum tolerance amongst a range of pine species and hybrids of potential interest to forestry in South Africa. Significant differences
in susceptibility were also found among clones of two P. radiata families. The most tolerant trees were P. elliottii × caribaea and P. patula × oocarpa hybrids, while the most susceptible species were P. patula, P. greggii and hybrids of these two. This is the first trial considering the susceptibility of Pinus hybrids, Pinus clones and some P. patula provenances, and the results indicate excellent potential for breeding for tolerance to pitch canker in South Africa.
Application The accurate selection of disease tolerant planting stock for the South African forestry industry is crucially important
for the continued sustainability of this important industry. The work described here provides valuable information on an artificial
inoculation technique that will assist the industry in screening trees for tolerance to the pitch canker fungus, F. circinatum. It also provides some indication of the relative susceptibility of a number of Pinus spp., hybrids and families currently being evaluated in the country. 相似文献
42.
ArcView GIS在林业制图方面的应用 总被引:1,自引:0,他引:1
应用地理信息软件ArcView GIS在林业制图方面的二次开发,编制出适用的应用程序,操作简单易行,提高了生产效率,为形成规模生产、实现林业制图自动化程度奠定基础。 相似文献
43.
应用MapGIS实现属性数据连接方法初探 总被引:1,自引:0,他引:1
利用森林资源二类调查获得的资料建立空间数据库与属性数据库,探索实现空间数据库与属性数据库有机结合的方法。 相似文献
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《黄土高原林业数据库》的研建 总被引:1,自引:0,他引:1
从黄土高原区域性出发,确定了研建工作的指导思想、文献收录范围及文献源,并对文献标引的一致性、专指性、组配标引、标引深度等问题进行了技术探讨。 相似文献
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GU WanchunResearch Institute of Forestry. Chinese Academy of Forestry. Beijing China 《中国林业科技(英文版)》2002,(1)
The present situation of forest tree genetic germplasm resources research and conservation in China is introduced which including the background, decision-making of conservation strategies and principles, the plan of area division and tree species classification, the sample strategy of germplasm conservation, the advances in conservation pattern and related technologies research, the achievements of germplasm conservation and utilization in China, and the problems to be solved. The recent achievements and data related are listed. 相似文献
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