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91.
Fourteen aphid species belonging to eight genera and three families of the superfamily Aphidoidea were presented from Isparta
region in fruit tree orchards. Among these, Dysaphis plantaginea, Aphis pomi and Dysaphis devecta, which cause harm to apples, are the most common species in the area because of the high amount of apple production. In addition,
eight species from the family Coccinellidae (Coleoptera), three from Syrphidae (Diptera) and one species from Forficulidae
(Dermaptera) were found as predator. Totally, eight species were determined as parasitoids from the families Aphidiidae, Aphelinidae
and Pteromalidae (Hymenoptera). 相似文献
92.
93.
Morphological variance and natural types' division of plus trees ofLarix principis-rupprechtii Mayr.
The phenotypic characteristics of the plus trees ofLarix principis-rupprechtii such as stem form, branch angle, branch/stem ratio, branch density, the crown width, crown length, number of short branch
over 5-cm branch segment in length, and the leaf number of each short branch were investigated in seed orchard in the Changcheng
Mountain, Shaanxi Province. According to the morphological characters, the plus tree clones ofLarix principis-rupprechtii were classified into 4 natural types: the narrow-dense-crown type, wide-dense-crown type, wide-sparse-crown type, and the
narrow-sparse-crown type. The result of the cluster analysis showed there was a very significant difference in tree growth
among the four natural types. While comparing the tree growth of four natural types for the last ten years, it was found that
the performance order of various types from good to bad is as follows: the narrow-dense crown type > the wide-dense crown
type > the wide-sparse crown type > the narrow-sparse crown type. The plus trees of narrow-dense-crown, as a fine type, should
be paid great attention to production and prepared to popularize.
Biography: ZHANG Xin-bo (1956-), male, Senior engineer of Shanxi Academy of Forestry Science and Northern Research Institute of Forestry
of China, Taiyuan 030012, P. R. China
Responsible editor: Chai Ruihai 相似文献
94.
具有广阔发展前景的几种云南天然香料 总被引:1,自引:0,他引:1
叙述了云南省天然香料资源开发利用简况及生产现状,提出了发展香料产业区域布局的设想。重点论述了香荚兰、肉桂、薄荷的国内外生产动向及在云南的发展现状和前景。 相似文献
95.
大围山自然保护区森林生物多样性生态服务功能评价 总被引:1,自引:0,他引:1
根据收集到的资料,参考国内外关于生物多样性生态服务功能的相关理论知识及其价值的评价方法,综合运用直接经济价值评估法、影子工程法、费用替代法、机会成本法、碳税法等价值评价的方法,对大围山自然保护区生物多样性生态服务功能进行了经济价值计算和评价。 相似文献
96.
福建武夷山自然保护区珍稀、濒危和特有植物及其分布 总被引:7,自引:0,他引:7
在收集整理20多年保护区野外植物调查数据基础上,总结了福建武夷山国家级自然保护区珍稀、濒危及中国特有属植物分布。列入国家重点保护的野生植物共计35种,其中属国家Ⅰ级保护植物3种,国家Ⅱ级保护植物19种,国家Ⅲ级保护植物13种。列入《中国濒危植物红皮书》国家重点保护的珍稀濒危植物28种。高等植物模式产地种共记录47种。中国特有属植物共计27属31种,其中单种属12属12种,少种属9属10种,多种属6属9种。 相似文献
97.
98.
WANGXian-cheng 《林业研究》2003,14(3):259-262
Changbai Mountain forest area is not only is a national timber base but also a green ecological defense for Songliao Plain of NE China. The Natural Forest Protection Project of this area has an important bearing on the social and economic sustainable development of Jilin Province or even the whole forest area in NE China. This paper summarized general conditions of natural forest in Changbai Mountain state-owned forest area and put forward six problems need to be urgently solved and five strategic suggestions on natural forest protection and sustainable management. 相似文献
99.
Genetic diversity of Populus euphratica populations in northwestern China determined by RAPD DNA analysis 总被引:1,自引:0,他引:1
Five Populus euphratica Oliver populations in northwestern China were analyzed using RAPD DNA markers to determine genetic diversity among and within populations. One hundred-and-five polymorphic bands were observed, ranging in size from 250 bp to 1700 bp, using 10 primers. Only one population on the north side of the Tianshern Range had a unique band common to all individuals that was not found in individuals from populations in the Tarim River valley. Intra-population genetic diversity was high in two populations along the Tarim River and low in the other three populations. There was no significant correlation between genetic distances and geographic distances. The result of correspondence analysis shows that the individuals from the three populations with low genetic diversity are isolated from each other. The result of cluster analysis based on genetic distance shows that the population in the Tianshern Range is genetically distant from the other populations. These results suggest that the Tianshern Range population was genetically isolated from the other populations. 相似文献
100.
巴黎翠凤蝶在甘肃白水江自然保护区1年2代,以蛹越冬,翌年3月下旬越冬蛹开始羽化,4月下旬至5月初为第1代成虫羽化高峰期,第2代成虫羽化高峰期在6月底7月初;寄主为芸香科的飞龙掌血、柑橘类等植物;成虫喜访白色系的花,也好在臭水沟处群聚嬉戏,一般在常绿林带的高处活动,飞行迅速,警觉性高而且很少停息,难以捕捉。红基美凤蝶在白水江自然保护区1年2代,以蛹越冬,翌年4月初越冬蛹开始羽化,4月下旬为第1代成虫羽化高峰期,6月底7月上旬为第2代成虫羽化高峰期;7月下旬成虫数量减少,但直至9月仍可见到成虫;7月上旬产卵高峰期,9月初为化蛹高峰期;直到10月上中旬还可见幼虫;幼虫5龄,历期25~35d;寄主为柑桔等芸香科植物。 相似文献