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1.
洪春芳 《湖南林业》2008,(11):25-25
马尾松球果小卷蛾发生成片危害,致使当年球果提早枯落,损坏嫩梢造成枝枯顶秃,干形弯曲,严重影响马尾松的正常生长。  相似文献   

2.
马尾松是我国南方飞播造林、绿化荒山及用材林的主要树种,每年种子需求量很大。由于马尾松球果取种困难,难以满足生产要求。为此,我们队1984年开始进行了马尾松球果处理工艺的试验研究工作。马尾松球果处理即从马尾松球果中得到带翅种子的过程,主要包括球果预处理、球果干燥、开裂球果脱籽三个工序。虽然近年引进并相继研制  相似文献   

3.
1990年至1992年我们对黄平马尾松种子园球果害虫进行了调查研究,结果为:1、危害马尾松种子园球果害虫主要是油松球果小卷蛾。2、球果害虫危害高峰期在5月底至6月初。3、种源间、无性系间、同一无性系个体之间球果害虫的危害程度无明显差异.4、球果害虫危害程度与定植密度(株行距)无明显差异。5、人工摘除虫害是防治球果害虫的有效方法之一.  相似文献   

4.
浙江省蛀食松梢球果的蛾类害虫   总被引:3,自引:0,他引:3  
在浙江省的马尾松、黑松、湿地松、火炬松、黄山松上采集到为害嫩梢和球果的蛾类昆虫12种,危害严重的有微红梢斑螟、松实小卷蛾和油松球果小卷蛾,火炬松严重受害、湿地松则轻微,不同梢果害虫对松树种类、松梢和球果有选择性,几种害虫蛀食同一球果的混合发生是这类害虫明显的发生特点;编制了幼虫、蛹和成虫的识别检索表,列出寄生天敌昆虫名录,提出了防治方法。  相似文献   

5.
在浙江省的马尾松、黑松、湿地松、火炬松、黄山松上采集到为害嫩梢和球果的蛾类昆虫12种,危害严重的有微红梢斑螟、松实小卷蛾和油松球果小卷蛾,火炬松严重受害、湿地松则轻微,不同梢果实虫对松树种类、松梢和球果有选择性,几种害虫蛀食同一球果的混合发生是这类害虫明显的发生特点;编制了幼虫、蛹和成虫的识别检索表,列出寄生天敌昆虫名录,提出了防治方法。  相似文献   

6.
在对长白松、赤松和樟子松不同性系或植株的球果形态特征(球果形状、大小、颜色和种鳞鳞盾隆起、鳞盾脊线明显程度),以及其球果的自然开裂时间进行比较后,认为目前分布于白河林业局的长白松天然纯林,起源于赤松×樟子松的天然杂种。它们是在经过了长期自然选择后所保存下来的优良杂种后代。  相似文献   

7.
采取平均木法实测不同立地条件的 10年生黄山松球果生物量 ,阐明黄山松球果生物量与立地条件以及测树因子之间的相互关系。 10年生黄山松山脊球果生物量最高平均每株 0 5 8kg ,而山坡最低为 0 4kg。应用树高和胸径分别推导出预测黄山松球果生物量的回归方程。  相似文献   

8.
黄山松球果害虫主要有松实小卷蛾和松果梢斑螟的幼虫,它们是一类生活隐蔽、危害严重、防治难度大的钻蛀性害虫,通过几年室内外的反复试验研究,提出了防治黄山松主要球果害虫的农药品种、用量(浓度)及施药的最佳时间和方法等。  相似文献   

9.
马尾松球果小卷蛾幼虫混合种群空间分布型与抽样技术研究兰星平,杜凌(贵州省森林病虫检疫防治站贵阳550001)(贵州省种苗站贵阳550001)陈恩军,黄丽(林业部种苗总站北京100714)(贵州黄平县横坡林场黄平556100)关键词马尾松,种子园,球果...  相似文献   

10.
施肥管理对马尾松球果产量的影响   总被引:2,自引:0,他引:2  
对马尾松种子园进行12种施肥管理试验表明:不同的施肥管理措施对马尾松球果产量产生显著差异,合理施肥可以提高马尾松球果产量和种子品质。  相似文献   

11.
本文记述了中国松叶蜂昆虫两新种,马尾松吉松叶蜂和油松吉松叶蜂。文中附有形态特征图4幅。  相似文献   

12.
Chemical study and medical application of saponins as anti-cancer agents   总被引:1,自引:0,他引:1  
Saponins are a group of naturally occurring plant glycosides, characterized by their strong foam-forming properties in aqueous solution. The presence of saponins has been reported in more than 100 families of plants out of which at least 150 kinds of natural saponins have been found to possess significant anti-cancer properties. There are more than 11 distinguished classes of saponins including dammaranes, tirucallanes, lupanes, hopanes, oleananes, taraxasteranes, ursanes, cycloartanes, lanostanes, cucurbitanes and steroids. Due to the great variability of their structures, saponins always display anti-tumorigenic effects through varieties of antitumor pathways. In addition, there are a large amount of saponins that still either remain to be trapped or studied in details by the medicinal chemists. This article reviews many such structures and their related chemistry along with the recent advances in understanding mechanism of action and structure–function relationships of saponins at the molecular and cellular levels. These aglycones have been described and their classification and distribution have been listed in the review. Some special saponins with strong antitumor effects have also been exhibited. Ginsenosides, belonging to dammaranes, have been found beneficial targeted on inhibition of tumor angiogenesis by suppressing its inducer in the endothelial cells of blood vessels, and then on prevention of adhering, invasion, and metastasis of tumor cells. Dioscin, one of the steroidal saponins, and its aglycone diosgenin also have been extensively studied on its antitumor effect by cell cycle arrest and apoptosis. Other important molecules discussed include oleanane saponins such as avicins, platycodons, saikosaponins, and soysaponins along with tubeimosides.  相似文献   

13.
Decomposition of Scots pine needle litter originating from five stands treated with different amounts of nitrogen fertilizer was measured over a 4‐year period in a mature Scots pine forest. The litter types, which differed in initial concentrations of nitrogen, phosphorus, potassium, and sulfur, but not in gross organic composition, were studied with respect to mass loss, ingrowth of total fungal mycelium, and net release of nutrients. During the first year of decomposition, rates of mass loss and ingrowth of fungal mycelium were highest in the nutrient‐rich litter. Phosphorus concentration was found to be the main factor affecting mass‐loss rate, and the rate of fungal ingrowth was positively correlated with initial nitrogen concentration. After this initial period, decomposition rates decreased, and after 4 years, accumulated mass loss and amounts of fungal mycelium were similar in all five litter types. These findings may be due, in part, to a lower rate of lignin decomposition in nitrogen‐enriched litter. Of the elements, potassium and magnesium were most rapidly lost from the litter, and their release was most pronounced during the first year. Calcium release was proportional to the loss in organic matter. Initially, the release of nitrogen and phosphorus was positively related to their concentrations in litter, however, during later stages of decomposition the differences among litter types levelled out. There was a tendency for concentrations of all elements, except nitrogen, in the different litters to approach similar levels as decomposition proceeded. Thus, after 4 years the nutrient composition of the various litter types was very similar, except for higher nitrogen concentrations in the originally most nutrient‐rich litters. The importance of the results in terms of substrate quality in fertilized as well as in non‐fertilized forests is discussed.  相似文献   

14.
一个世纪来黑龙江省森林景观动态研究   总被引:1,自引:0,他引:1  
With the help of GIS tool of ARC/INFO,ARCVIEW and FRAGSTATS,the map of forest resource distribution of Heilongjiang Province was analyzed in 1896,1949 and 1981.Using total area,mean patch size,patch density,coefficient of patch size variation,mean patch fractal dimension and mean shape index,we studied the change of forest landscape pattem and the change of each patch types in this region.As a result,the total area of forest landscape and mean patch size decreased sharply,the quantity and density of patches increased,the juxtaposition of patches weakened,the shape of patch tended to become regular,and the border of patch simplified.All these showed that the forest landscape of this area tended to fragment gradually,and the fragment of Korean pine forest is the severest.the diversity of whole forest landscape and the eveness of landscape types distribution reduced gradually.Human impact,instead of climate change and forest community succession,is the most important reason for such dramatic chages.  相似文献   

15.
对桂北全州县咸水镇种植的尾赤桉、尾巨桉等6个速生桉无性系的生长表现、寒害状况进行了调查分析,结果表明:不同速生桉无性系间生长差异显著,以无性系3(尾巨桉)、5(尾巨桉)、6(尾赤桉)3个无性系号生长最好,1号(柳窿桉)无性系生长最差。冻害是检验速生桉无性系能否适应的关键指标,所种植的速生桉无性系受冻严重,在冰雪袭击下所有试验树木均被全部压断,部分树木还被冻死而不能萌芽。类似全州县成水镇的气候条件不适宜种植尾巨桉、尾叶桉、柳窿桉等速生桉无性系。  相似文献   

16.
采用典型样株和随机取样的方法,对五味子种耔性状进行系统研究.结果表明:无性系间的种籽横径、种籽纵径、种籽厚度、种籽千粒重、种仁千粒重、种仁含油率等性状的差异达极显著水平;在供试的20个无性系中,9911、9907、9913、9919、9918、9914等6个无性系种仁含油率较高,分别为70.17%、69.77%、68.99%、67.51%、65.97%、64.15%;五味子种油的形成、积累与无性系的种籽千粒重、种仁千粒重、种籽横径、种籽纵径等指标关系不密切,而与种耔厚度关系密切,相关系数为0.670,相关关系达极显著水平.本研究结果可为以高含油率为目标的五味子品种选择提供依据.  相似文献   

17.
为了明确福建省樟树溃疡病的病原菌种类,对福建省福州市仓山区、三明市明溪县、南平市建阳区和顺昌县4个地区采集的樟树枝干溃疡样本进行分离、纯化和致病性分析,将病原菌进行系统形态学观察,并结合代表菌株的核糖体基因内转录间隔区(ITS)、翻译延伸因子(EF-1α)、RNA聚合酶Ⅱ大亚基(RPB2)和β-微管蛋白(BT)基因序列进行同源性分析,构建进化树,最终确定病原菌种类。结果表明,在福建省不同地区内采集到的75份樟树溃疡样本,经过组织分离、纯化和致病性检测,得到43个病原菌株,根据观察病原菌的菌丝生长状态和孢子特征,并结合系统进化树的结果,得到小新壳梭孢(Neofusicoccum parvum)、可可毛色二孢(Lasiodiplodia theobromae)、假可可毛色二孢(Lasiodiplodia pseudotheobromae)和Lasiodiplodia iranensis 4种类型菌株。接种菌株后发病症状与野外发病症状相同,但致病程度不同,其中小新壳梭孢最强,可可毛色二孢次之,L.iranensis最弱。  相似文献   

18.
Five Aigeiros section poplar clones were adopted as parents to produce five full-sib families through cross-breeding. Morphological, ecophysiological, and growth characteristics of the five parents and their 15 superior F1 generations were investigated during 45 days of flooding followed by a 10-day recovery period. Cuttings were subjected to two treatments: watered (control) and flooded to 10 cm above the soil surface. Results showed that flooded cuttings showed significant reduction in growth of height, root-collar diameter and leaf area, and root and total biomass yield. All 20 clones formed hypertrophied lenticels and adventitious roots by day 6–14 of flooding. In flooded cuttings, net photosynthesis, stomatal conductance, transpiration, and chlorophyll fluorescence were decreased significantly compared with the control. After flooding ended, all plants recovered rapidly. Generally, progenies showed higher growth of height, root-collar diameter, root biomass and leaf area than their parents both under flooding and control conditions, showing that heterosis existed in F1 generations, regardless of flooding. However heterosis was lower under flooding conditions than in the control. Under flooding, the highest heterosis of higher-parent in height and root-collar diameter were 68.63 and 20.83%, respectively. Variability of flood tolerance among progenies was clear in growth of height and root-collar diameter. Selection criteria for parents in cross-breeding were different between control and flooding. Relative effect values of the specific combining ability (SCA) and relative effect values of the general combining ability (GCA) of parents were more important than their flood tolerance. Progenies with a higher level of flood tolerance could be obtained, even from parents intolerant to flooding. In terms of breeding, height growth would be most important characteristic to measure in flooding conditions, and root-collar diameter growth was also very useful. Based on all measured values, the tested 20 clones were classified into three groups using hierarchical cluster analysis. Clones Lu, E4, E9, E29, A2, A8, A9, B1, B3, B4, and D8, were flood-tolerant. Clones Lf, Ha, Lm, D1, D7, F9, and F21 were moderately flood-tolerant. Clones Sm and F13 were flood-susceptible.  相似文献   

19.
本文利用现有资料以及实地调查,对川西地区(甘孜、凉山)的鱼类多样性进行了分析研究。结果表明:①川西地区共有鱼类9目19科82属148种和亚种,分别占整个四川(含重庆)鱼类的61.16%和整个中国鱼类的6.15%;②各科鱼类的种数分布为鲤科最多,为82种,占整个川西鱼类总数的55.41%,其次为鳅科,占14.19%。③川西地区是鲤科鱼类的东亚类群向西扩布的西缘地带,是青藏高原鱼类区系向东延伸的东缘地区,同时是南亚鱼类向北分布的北缘区域;④川西鱼类的垂直分布状况因地貌、海拔高度变化以及生态环境的差异等呈现出一定的规律性。此外,本文还对川西鱼类资源的保护提出了建议和对策。  相似文献   

20.
竹业引领人类生活更美好   总被引:4,自引:4,他引:0  
文章介绍了竹材在建筑、家具、交通、日用品等领域的应用现状,分析了竹材在性能、成本、资源量及环保等方面具有的多种优势,以及木材、塑料、钢材、陶瓷应用局限性和劣势,提出了竹木并举、以竹代塑、竹钢协同、竹瓷互补潜在的创新应用方向。在当前化石能源日益枯竭、环境压力越来越大的情况下,发展竹产业、应用竹产品是一项改变人类生活、促进绿色发展的重要举措,是健康生活、生态人居、绿色发展的正确方向。  相似文献   

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