首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 203 毫秒
1.
银杏新害虫—百荚螟豆荚螟以第二代幼虫危害银杏果实和核仁。被害银杏果实的核仁全部被食光,种核内只留下虫粪,严重影响银杏种实的产量和质量。该虫5月下旬第二代幼虫孵化后,先吐丝结网隐蔽其内,取食银杏果实,随后钻入种核危害。一头幼虫一生只取食一个种核。7月底...  相似文献   

2.
黄宽颚步甲 Parna rufotesoea Jedl 曾被报道是茶园害虫中的一种天敌昆虫,在近期的研究工作中又发现该步甲亦取食乌桕金带蛾幼虫。因此笔者在以往研究其生物学特性基础上重点对该步甲取食乌桕金带蛾 Eupterote sapivora Yang 幼虫进  相似文献   

3.
虫情监测是森林害虫综合治理的前提。直接观测虫情,常因树木高大而难以实现。对我国林业大害虫马尾松毛虫(Dendrolimus punctatus),已有较理想的模型,通过对林间落粪的调查来估计幼虫数。由于低密度虫情监测尤为困难,而用落粪作间接观测的价值就随之增加,林间一定时段内的落粪是幼虫种群在该时段内活动的结果,其分布则是该时段内种群分布的综合反映。可以设想,落粪分布与种群分布间存在一定关系。对落粪的调查取样,应建立在了解其分布特征的基础上。为此,研究了低密度幼虫种群的空间分布型及落粪分布的规律。  相似文献   

4.
泡桐茸毒蛾Dasychira sp.是危害泡桐的一种叶部害虫。1982—1984年该虫先后在河南省汝阳、临汝两县危害成灾,1987年又在偃师县大量发生,幼虫取食叶片,危害严重时,受害叶片仅剩叶柄。为摸清该虫的生物学特性,适时开展防治,作者对该虫进行了观察,现将观察结果初步整理如下。  相似文献   

5.
一、危害情况:杨干白尾象(虫甲)是我省主要害虫之一,对杨、柳、桦等幼树有毁灭性的危害,是森林植物检疫对象。我场的德隆地、兴隆庄等杨树人工林被害最严重。杨干白尾象虫甲主要危害青杨、加拿大杨、小叶杨和青皮柳,其中以小青杨被害最重。从一九六五年开始对此虫进行了观察和防治试验。据历年来的观察在幼虫阶段对树木危害最重,幼虫在树干的皮层内取食危害,因此,不易发现,2~3命幼虫在边材处危害,咬成不规则的浅坑.3命以后的幼虫开始蛀入木质部,自上或向下蛀  相似文献   

6.
靖远松叶蜂(Dipion jingyuanensis)是危害油松的重大森林害虫,1994年定为新种。该文对其形态、生物学特性、与环境因子的关系及主要天敌作了深入研究。此虫在山西省沁源,一般一年1代,以芯内预蛹(拟)在落叶层下越冬,成虫于6月间大量出现,少数有滞育现象,两年完成1代,雌雄性比为1:0.6每雌产卵120粒~229粒,有孤雌生殖现象,幼虫共8龄,每头幼虫取食针叶60根左右、纯林、疏林、阴坡虫口密度大,靖远松叶蜂病毒(NPV)、白僵菌、金头赘寄蝇、大山雀等22种天敌是制约该虫种群数量的重要环境因素。  相似文献   

7.
本文论述了热带森林害虫生物学的特殊性!包括世代、寿命、产卵延续期、异常生物学、滞育、休眠、拟态和伪装。经研究发现:热带林虫繁殖快,世代多,象虫寿命和产卵延续期长,球象幼虫别具一格的取食习性,摹拟眼镜蛇的赤顶粉蝶幼虫,用寄主花序伪装的母生花尺蛾幼虫等。  相似文献   

8.
光肩星天牛是检疫性害虫,主要危害杨树、柳树、榆树、沙枣等阔叶树种.光肩星天牛的幼虫寄生在树干上,从树干基部直至树梢都有寄生.幼虫开始在韧皮部和木质部之间取食,受害处流出树液,有木屑和红棕争虫粪排出.随着虫龄的增加,幼虫在边材穿凿横向坑道,坑道坡此靠近,在同一高  相似文献   

9.
山西阳泉地区松阿扁叶蜂发生情况调查初报   总被引:1,自引:0,他引:1  
松阿扁叶蜂Acantholyda posticalis Matsumura是近几年发生在山西省阳泉市盂县庄头林区油松上的主要食叶害虫,每年7月下旬至8月上中旬危害.该虫种群数量大,扩散蔓延迅速,习性特殊.幼虫吐丝做巢,咬断针叶拖入巢内取食,但仅取食少量针叶使大部分针叶落地损失.  相似文献   

10.
鸟类与森林     
鸟类是害虫的天敌。在森林中,众多的鸟类大量捕食害虫,对抑制森林虫害起了十分重要的作用。鸟类捕食害虫的本领令人惊叹,科学工作者近年来又发现食虫鸟类还有另外一种本领,对抑制森林害虫同样十分有效,那就是扩散和传播对昆虫种群致命的昆虫病毒。  相似文献   

11.
马尾松天然林病虫害调查   总被引:1,自引:0,他引:1  
通过对马尾松Pinus massoniana Lamb天然林及其速丰试验林、针阔混交天然林的调查,计有病虫19种,其中病害6种,害虫13种,天敌昆虫15种。调查表明,病虫种类和被害率,试验林较低,施肥区最低,混交林明显比纯林少。  相似文献   

12.
马尾松是我国松属树种中地理分布最广的一种,也是南方的造林先锋树种和主要用材树种。文中从物理力学性能、纤维特性以及渗透性等方面论述了马尾松木材材性特点,介绍了马尾松木材干燥及脱脂处理技术、木材蓝变及其防治方法,总结了马尾松木材在实木利用、人造板生产等领域的应用现状,展望了马尾松木材加工利用的发展前景。  相似文献   

13.
Water relation parameters of bare-root seedlings of Chinese fir (Cunninghamia lanceolata Hook.)and Masson pine (Pinus massoniana Lamb.)were measured and changes of root growth potential as well as field survival rate of both species were studied after the bare-root seedlings were exposed in a sunny field condition.the results showed that masson pine had a lower osmotic potential(-2.07Mpa) at turgor loss point and at full turgor(-1.29Mpa),compared with Chinese fir(-1.80Mpa and -1.08Mpa respectively).The parameter Vp/Vo(63.27%) of Masson pine was higher than that of chinese fir (58.03%).This means that Masson pine has a stronger ability to tolerate desiccation,compared to Chinese fir according to analysis of above water relation parameters.Root growth potential and field survival rate decreased with prolonging duration of exposure.The field survival rate of both species was reduced to less than 40% after the seedling being exposed only two hours.Water potentials of -1.60 Mpa and -1.70 Mpa were suggested to be critical values for Chinese fir and Masson pine respectively in successful reforestation.  相似文献   

14.
Reported in this paper are our findings of the study on changes in species diversity of different Masson pine communities after the invasion of Bursaphelenchus xylophilus (Steiner and Buhren) Nickle and subsequent and different removal disturbance management approaches. Based on the results, the species diversity indices for the arbor layers of the different communities can be arranged in the following order (from high to low): 1) broad-leaved stand after the removal of all infected pine trees in the pure pine stand in Fuyang; 2) lightly infected Masson pine and Schima superba mixed stand in Fuyang; 3) uninfected stand mixture of Masson pine and Castanopsis fargesii as a control; 4) lightly infested pure Masson pine stand in Fuyang; 5) Quercus variables stand formed following the selective removal of infected pine trees from a mixed Masson pine and Q. variables stand in Zhoushan Islands; 6) pure young Masson pine stand formed following the removal of all infected pine trees from a pure Masson pine stand; 7) pure Liquidambar formosana stand after the removal of infected pine trees from a pure pine stand in Zhoushan Islands; 8) a mixed stand consisting of Pinus thunbergii and the Masson pine in Zhoushan Island; and 9) moderately infected Masson pine stand in Zhoushan Islands. All the three diversity indices (R 0 = richness, H′ = Shannon-Wiener index, and E = evenness) for the shrub layer did not show any significant differences among the various communities except for the pure pine stand in Zhoushan Island, which had the lowest diversity. The three indices for the herb layer of the pure young Masson pine, Q. variables stand, and L. formosana stand were higher than that of other stands. The integrated analysis showed that the Masson pine forest in different geographical situations and extent of damage had distinct disparity, just as in different disturbance degrees and restoring manners. We created the “index of disturbing intensity of stump and fallen woods” (IDISFW) to represent the degree of disturbance of tree removal to plant diversity. We found that the relationship between the species diversity index and the IDISFW shows both a lower and higher degree of removal disturbance that follows the “mid-altitude bulge” theory. Specifically, both excessive and insufficient removal of infected trees will cause a decline of plant species diversity to a certain degree. Covariance analysis indicated that different IDISFW had no significant effects on the species diversity of the arbor layer, but had different impacts on that of the shrub and herb layers, and therefore can be used to assess changes in species diversity of different Masson pine communities after the invasion of pine wood nematode. __________ Translated from Chinese Journal of Applied Ecology, 2006, 17(7): 1,157–1,163 [译自: 应用生态学报]  相似文献   

15.
马尾松共生菌根真菌调查研究   总被引:8,自引:1,他引:8       下载免费PDF全文
通过野外调查和室内鉴定,已查明与马尾松共生的菌根真菌27个种,其中有19个种是国内首次报道的。编制了马尾松菌根真菌名录(一)。马尾松隶属外生菌根树种,它可与多种菌根真菌共生形成典型的外生菌根的结构。  相似文献   

16.
The invasion of Bursaphelenchus xylophilus (pine wood nematode, PWN) carried by Monochamus alternatus predominately attacks Masson pine (Pinus massoniana) forests and causes great economic losses in China. In this study, we assessed whether the effect of the invasion of PWN is different between island and inland forests. Arthropods were sampled in Fuyang (inland) and Zhoushan (island) counties in Zhejiang Province with sweep netting and light traps at four plots. During two field periods (May to June 2004 and September to October 2005) a total of 21,916 insects, representing 384 species belonging to 99 families and 15 orders, were collected in the sample plots from the island, whereas, from the inland forest a total of 29,262 insects, representing 308 species belonging to 96 families and 13 orders, were found. A hierarchical cluster analysis (HCA) and one-way ANOVA, based on the composition of different arthropod guilds, were performed. The results showed that there was no significant difference in the composition of arthropod communities at the family level between inland and island. But these two habitats had a significant effect on the composition of species, individuals, sub-communities and energy class levels. Statistically, the composition of the two orders, Lepidoptera and Diptera, in the two habitats were significantly different.  相似文献   

17.
The electrolyte conductivity and activity of dehydrogenase of bare-root seedlings of both Chinese fir (Cunninghamia lanceolata (Lamb.)Hook.)and Masson pine (Pinus massoniana Lamb.) under freezing and desiccation treatments were studied.The results showed that needle electrolyte conductivity of both speices increase significantly after freezing treatment and there are no significant differences in needle electrolyte conductivity between the two species.The dehydrogenase activity(ARD) of fine roots of both Chinese fir and Masson pine was negatively correlated with increasing freezing and desiccation.The results suggest that both electrolyte conductivity and dehydrogenase activity could be used as quick indicators of Chinese fir and Masson pine bare-root seedling quality.  相似文献   

18.
利用东北落叶松,南方杉木、马尾松、栎类和西北山杨5个树种(组)的实测数据,对3种平均生物量转换系数计算方法进行了比较分析,并利用假设检验方法,对落叶松和马尾松、2个区域杉木的生物量转换系数进行了差异显著性检验。结果表明:利用算术平均法计算平均生物量转换系数是合适的,阔叶树的生物量转换系数大于针叶树;落叶松和马尾松的生物量转换系数无显著差异,而2个区域杉木的生物量转换系数差异显著。  相似文献   

19.
松毛虫种间杂交及其遗传规律的研究   总被引:10,自引:0,他引:10  
本文报道了我国最严重的森林害虫———松毛虫种间杂交试验的研究结果。研究表明,马尾松毛虫(DendrolimuspunctatusWalker)、油松毛虫(DendrolimustabulaeformisTsaietLiu)、赤松毛虫(DendrolimusspectabilisButler)、落叶松毛虫(DendrolimussuperansButler)相互间都可以进行杂交,亲缘关系较近。其中,油松毛虫和赤松毛虫分别与马尾松毛虫进行杂交,无论正交或反交都可以产生有生育力的F1代,F1代自交产生F2代,证明在它们之间不存在生殖隔离。另外,油松毛虫、赤松毛虫和马尾松毛虫分别与落叶松毛虫的种间杂交也能进行,并产生F1代杂种松毛虫,但在人工饲养条件下幼虫死亡率高,经过多年反复试验,均未能完成F2代。另外,还对其形态学特征和染色体进行了初步研究。研究结果表明,赤松毛虫、油松毛虫和马尾松毛虫确系同一物种,但由于长期适应不同的生态环境,相互间的形态及生物学特性已有一定程度的差异,根据动物学命名法的有关规定,我们认为油松毛虫和赤松毛虫应分别定名为马尾松毛虫地理亚种,即油松毛虫(Dendrolimuspunctatust  相似文献   

20.
水分和热胁迫处理对三个针叶树种苗木叶绿素荧光的影响   总被引:7,自引:0,他引:7  
本文测定了三个周期水分和热胁迫处理对杉木、马尾松和北美乔柏苗木叶绿素荧光的影响。结果表明:三个树种的可变荧光与最大荧光之比值(Fv/Fm)对水分胁迫的反应不同。水分胁迫处理后北美乔柏的(Fv/Fm)值大大降低,而杉木的(Fv/Fm)值只有轻微下降,马尾松的(Fv/Fm)值则没有显著变化。实验结果还表明:热胁迫处理对三个树种的(Fv,Fm)值都有显著影响。就三个水分和热胁迫周期而言,研究发现:在每个水分和热胁迫周期结束时测定的杉木和马尾松(Fv/Fm)值没有显著差异。但随着胁迫时间的延长,北美乔柏的(Fv/Fm)值显著下降。图4表4参20。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号