华山松木蠹象卵蛹及羽化孔空间分布型研究

对华山松木蠹象的卵、蛹及羽化孔的空间分布型研究,表明了该虫的卵、蛹、羽化孔在华山松上的分布均为聚集型,根据切比雪夫定理,应用最小二乘法求解,得出华山松木蠹象卵、蛹及羽化孔的空间分布模型.     

华山松木蠹象卵蛹及羽化孔空间分布型研究

对华山松木蠹象的卵、蛹及羽化孔的空间分布型研究，表明了该虫的卵、蛹、羽化孔在华山松上的分布均为聚集型，根据切比雪夫定理，应用最小二乘法求解，得出华山松木蠹象卵、蛹及羽化孔的空间分布模型。     

华山松木蠹象为害特性的初步研究

经对华山松木蠹象历时２年的调查和试验研究,初步了解华山松木蠹象的分布、寄主域,为害特性,为害方式及为害部位。结果表明：该虫在滇东北,滇南,滇中及滇西地区均有分布;其寄主主要是松科的多种树种,该虫具有为害致死速度快,扩散蔓延速度快,只为害健康植株,成虫羽化历期长,防治难度大的特点。本项研究为制定一套经济有效的华山松木蠹象综合防治措施打下了基础。     

华山松木蠹象为害特性的初步研究

经对华山松木蠹象历时２年的调查和试验研究，初步了解了华山松木蠹象的分布、寄主域、为害特性、为害方式及为害部位。结果表明：该虫在滇东北、滇南、滇中及滇西地区均有分布；其寄主主要是松科的多种树种，该虫具有为害致死速度快，扩散蔓延速度快，只为害健康植株，成虫羽化历期长，防治难度大的特点。本项研究为制定一套经济有效的华山松木蠹象综合防治措施打下了基础。     

华山松木蠹象防治指标研究

在曲靖市海寨林场遭华山松木蠹象危害的华山松林分内设样地并作解析木观测，结果表明，华山松木蠹象危害指数与华山松材积损失率间有明显的相关关系，其相关关系可用一元回归方程表示为Y=-0.398654+0.055908X(X为华山松木蠹象危害指数，Y为华山松材积损失率)在此基础上，考虑不同的立木生长量、木材价格、防治费用和防治效果，进一步推算出华山松木蠹象防治指标的动态模型为X     

木蠹象属Pissodes Germar系统学研究综述

木蠹象属Pissodes Germar昆虫是松树、云杉和冷杉等针叶树的重要害虫之一。本文从木蠹象属的研究现状出发,介绍了该属的研究历史,对该属的建立时间进行了澄清和界定,并对其寄主和分布地进行了总结。木蠹象属全世界共记述有效种类46种,分布在17个国家和地区,其主要寄主植物为松属、云杉属和冷杉属等针叶类树,在中国危害较重的有红木蠹象、云南木蠹象和华山松木蠹象。     

山西省首次发现华山松木蠹象蛀干害虫

笔者介绍了华山松木蠹象在山西省首次被发现的过程和发现地概况,描述了华山松木蠹象的形态特征与发生规律,分析了华山松木蠹象在中国与山西省的危害情况。并针对其在山西省的潜在危害性提出了预防建议,以期为今后防治华山松木蠹象提供理论参考。     

云南木蠹象和华山松木蠹象大面积防治实用技术

作者总结了云南木蠹象和华山松木蠹象大面积防治和药物筛选试验的成功经验，提出了一套包括防治思路、防治策略、药物防治、蠹害木清理和危害木处理在内的大面积防治技术。     

利用管氏肿腿蜂防治华山松木蠹象技术研究

首次将管氏肿腿蜂应用于华山松木蠹象的防治实践,结果表明:该蜂对华山松木蠹象有很强的搜寻能力。在室内管氏肿腿蜂对华山松木蠹象寄生率最高达71.43%,最低51.61%。在林内防治试验中,它对华山松木蠹象寄生率最高达41.67%,最低22.22%;防治效果均在25%以上,最高达38.27%。     

木蠹象属(鞘翅目:象虫科)的种类、分布、寄主植物及潜在入侵威胁

木蠹象属是以松树木蠹象为模式种建立的属,是鞘翅目、象虫科、木蠹象亚科的唯一属.该属目前已记录种类46种,29种分布于美洲,18种分布在欧洲和亚洲,其中耐猛木蠹象是美洲、欧洲和亚洲共有的种类,它分布于美洲的美国、加拿大,欧洲的俄罗斯和亚洲的日本.木蠹象属许多种类是针叶树的重要害虫,且极易通过人为携带传播扩散.有3种分布区跨越欧洲和亚洲,葛氏木蠹象分布于俄罗斯的欧洲部分、德国和瑞典,亚洲的中国、日本和俄罗斯的亚洲部分(西伯利亚);圆角木蠹象分布于俄罗斯的欧洲部分和中国;樟子松木蠹象分布于法国和中国.木蠹象属的寄主植物均为针叶树,包括5属39种,以松属为寄主植物的有26种木蠹象,以云杉属、冷杉属、落叶松属和黄杉属为寄主植物的木蠹象分别为9、5、4和1种.分布于中国的木蠹象有7种,其中粗刻点木蠹象和云南松木蠹象是特有种类,葛氏木蠹象、圆角木蠹象和樟子松木蠹象是与欧洲共有的种类,黑木蠹象、葛氏木蠹象和红木蠹象与日本共有,红木蠹象与韩国共有.分布于日本的耐猛木蠹象和瘤木蠹象、俄罗斯西伯利亚的凸眼木蠹象以及日本、俄罗斯和韩国均有发生的黄星木蠹象,以及在中国均没有分布的美洲的29种木蠹象,都属于应加强检疫的对象,防止人为携带传入我国.     

Variation in damage by terminal shoot insects among jack pine families

The susceptibility of jack pine, Pinus banksiana Lamb., to damage by the white pine weevil, Pissodes strobi (Peck) and the eastern pine shoot borer, Eucosma gloriola Heinrich, was examined over a three-year period (1994–1996) in a 400-family genetic test near New Liskeard, Ontario. Of the 7180 trees examined, white pine weevil damaged 1041 and eastern pine shoot borer damaged 1913 trees, yielding damage frequencies of 14.5% and 26.6%, respectively. Thirty families of jack pine never sustained weevil damage during the study period, while only one family escaped damage by the shoot borer. The expected, and observed, damage rates were significantly different for the weevil, but not for the shoot borer. There was no discernible spatial pattern in the incidence of shoot damage by either insect species, based on the geographic location of the parent trees. The data suggest that there is a basis for pursuing further studies to evaluate genetic resistance in tree improvement programs.     

秦岭华山松小蠹生态位研究

通过对秦岭林区海拔１６００～２２００ｍ的中山地带华山松小蠹虫种类和生态位的研究,结果表明：在秦岭林区入侵危害寄主华山松的小蠹虫有１９种,其中能构成竞争和共存的小蠹虫主要有１１种。虽然,这１１种小蠹虫具有各自不同的生态位宽度,且存在不同程度的生态位重叠,但各小蠹虫可依据其对寄主树木营养和空间需求的不同、种群密度的相互制约,以及入侵寄主树木时序的差异达到竞争的平衡和共存。秦岭华山松小蠹生态系统的建立,首先是由华山松大小蠹入侵健康华山松,并通过携带蓝变真菌入侵寄主树木,迅速克服寄主树木抗性系统,使寄主树木树势衰弱;其次松六齿小蠹、暗额星坑小蠹和松十二齿小蠹,作为秦岭华山松的主要次期性小蠹,迅速入侵衰弱的寄主华山松;最后其它次期性小蠹虫入侵寄主树木,利用寄主华山松剩余营养和空间。从而实现秦岭华山松立木小蠹生态系统的动态稳定。     

Extra Food Supply Decreases Damage by the Pine Weevil Hylobius abietis

It has been suggested that reduced damage by the pine weevil ( Hylobius abietis ) under shelter trees might result from more food being available under shelter trees than on clear-cuttings. The shelter trees provide an extra supply of bark on branches and roots. Moreover, shelter trees favour some species in the ground vegetation (e.g. bilberry, Vaccinium myrtillus ) that could be used as food by the weevil. Two similarly designed field experiments, studied whether the amount of pine weevil feeding on planted conifer seedlings was affected by the availability of other food sources. In the first experiment, fresh pine branches were placed weekly on the ground for 6 weeks on a fresh clear-cutting in southern Sweden. This significantly reduced the amount of feeding on seedlings in treated 20 2 20 m plots. In the second experiment, damage tended to increase after mechanical removal of field vegetation (mainly bilberry), but the effect was not statistically significant. In conclusion, extra food in the form of coniferous bark could relieve seedlings from pine weevil damage; however, any effect of this kind due to the presence of field-layer vegetation remains to be demonstrated. Finally, there may be long-term population effects because of the extra food that the shelter trees provide for the reproductive weevils.     

Changes in volatile terpene and diterpene resin acid composition of resistant and susceptible white spruce leaders exposed to simulated white pine weevil damage

Induced (traumatic) resin in white spruce (Picea glauca (Moench) Voss) leaders resistant or susceptible to the white pine weevil (Pissodes strobi Peck) was analyzed for volatile terpenes and diterpene resin acids after simulated white pine weevil damage. Leaders from 331 trees were wounded just below the apical bud with a 1-mm diameter drill, coinciding with the natural time of weevil oviposition in the spring. Leaders were removed in the fall, and the bark and xylem from the upper and lower regions of the leader extracted and analyzed by gas chromatography. Unwounded trees had low amounts of resin in xylem compared with bark. In response to wounding, volatile terpenes and diterpene resin acids increased in the upper xylem (area of wounding), with resistant trees showing a greater increase than susceptible trees. Wounding caused monoterpenes in particular to decrease in the lower region of the leader (away from the drilled area) in greater amounts in susceptible trees than in resistant trees. In response to wounding, the proportion of monoterpene to resin acid increased in the upper and lower xylem of resistant trees, and slightly increased in the upper xylem of susceptible trees. Monoterpene-enriched resin is more fluid than constitutive resin, and probably flows more readily into oviposition cavities and larval mines, where it may kill immature weevils. Loss of resin components in the lower xylem suggested catabolism and transport of these materials to the site of wounding; however, energetic and regulatory data are necessary to confirm this hypothesis. This study provides a basis for measuring the ability of a tree to undergo traumatic resinosis that could be used to screen for resistance to white pine weevil.     

INFLUENCE OF FIRE ON KOREAN PINE AND SCOTS PINE TREES IN PLANTATION

The plantations of korean pine(Pinus koraensis)and scots pine(Pinus sylvesrisvar.mongolica)are mainly pure stands.Fires are gradually causing problems in theseplantations and being paid much more attention recently.Study on the influence of fire ontrees and the adaptation to fire,therefore,is of great important to probe the fire ecologicalproperties and the protection ways of these two species.The results are as follows:Bothof the species are easily damaged by fire,but korean pine is more susceptible.In the samefire,korean pine is damaged more seriously than scots pine although they have the samesize.Young individuals have low fire resistant capacity and can be damaged seriously,andolder ones have strong fire resistance and can be damaged lightly.Up-hill fire makes aserious damage to the trees distributed in up-slopes with the reason of higher fireintensity.Down-hill fire makes a serious damage to the trees distributed in down-slopcswith the reason of higher fire severity.The larger deocambium area in t     

Damage by pine weevil Hylobius abietis to conifer seedlings after shelterwood removal

Abstract

Pine weevil (Hylobius abietis L.) damage to seedlings after overstorey removal was investigated in a survey study in six shelterwoods in the south–central part of Sweden. The shelterwoods predominantly consisted of Scots pine, except at one site where the shelter trees mainly consisted of Norway spruce. Before final cutting, 10 plots were laid out at each site and measurements of shelter trees and marked seedlings were taken. The seedlings were examined during the 2 years after final cutting. The study showed that removal of shelter trees increases the risk of severe damage by pine weevil and the variable that was most strongly correlated with the risk was the seedling root collar diameter. Both Scots pine and Norway spruce seedlings were severely damaged by pine weevil, and most of the feeding occurred during the first year after cutting. The amount of debarked area was significantly larger for Scots pine than for Norway spruce seedlings. Vitality (growth of the leading shoot before final cutting) of the seedlings also affected the probability of damage. Seedlings with high vitality were less damaged by pine weevil than seedlings with low vitality. For Scots pine the shelterwood density before final cutting was correlated to the intensity of pine weevil feeding after cutting. In conclusion, after the final cutting of a pine or spruce shelterwood, pine weevils will probably invade the area. To avoid serious damage, Norway spruce and Scots pine seedlings should have reached a diameter of at least 10–12 mm.     

Histological response of resistant and susceptible white spruce to simulated white pine weevil damage

The traumatic wound response of families of white spruce, Picea glauca (Moench) Voss, resistant or susceptible to the white pine weevil, Pissodes strobi (Peck), were compared after simulated weevil damage. Leaders from 331 trees were wounded just below the apical bud in the spring, coinciding with the natural time of weevil oviposition. A portable 1-mm diameter drill was used to drill 24 holes per leader. Leaders were removed in the fall and examined for evidence of traumatic resin canal formation. Drilled trees had a traumatic wound response 8 times greater than that of undrilled trees; however, undrilled trees also formed some resin canals in response to unknown causes. In the drilled trees, the traumatic wound response extended into the lower part of the leader, where it could possibly affect older larvae. Trees from resistant families responded with greater intensity than trees from susceptible families, by producing multiple rings of traumatic resin canals. Trees from resistant families also responded more rapidly than trees from susceptible families based on number of cells to the first ring of traumatic resin canals. Trees from some resistant families exhibited no traumatic resin canal formation, showing considerable within-family variation and suggesting that other resistance mechanisms might be important. In the year after drilling, there was a reduction in tree diameter growth and trees suffered a reduction in constitutive resin canals in the bark, which suggests some energetic cost of traumatic resin production. There was no indication that the extent of constitutive defenses, as measured by density of cortical resin canals before wounding, was related to the ability to produce traumatic resin canals. Screening trees based on their capacity to produce traumatic resin canals may be useful in selecting genotypes resistant to white pine weevil.     

Impact of invasion of pine wood nematode on the growth of dominant shrub Pleioblastus amarus in Pinus massoniana communities

When pine trees are invaded by pine wilt diseases,the severely infected pine trees will die and fall down,or they will be removed when found to be damaged by the disease.It gives rise to the invasion of other species in these empty niches originally occupied by pine trees,i.e.,competing surrounding trees or understory shrubs will invade the empty niches during the following years.As a result,the spatial distribution and pattern of the main tree species in a pine forest will change,and a niche variety in the...     

长白山北坡椴树阔叶红松林群落主要树种的年龄结构研究

通过对长白山林区椴树阔叶红松林伐根的大量调查 ,认为红松种群是由不同年龄阶段的群团状斑块组成 ,以多世代群居 ,优势世代之间没有一定的严格间隔期 ,在年龄结构图上往往出现两个或两个以上高峰。阔叶树在天然红松林中的分布呈群团状或散生 ,阔叶树的年龄也为异龄性 ,也为多世代共居。红松与阔叶树之间存在明显的动态消长关系 ,同龄伴生 ,异龄混生 ,形成复层异龄的针阔混交林 ,年龄结构与年生长关系的数学模型表明年生长量与年龄有正相关趋势 ,但林木年龄达到老龄时 ,生长有所减缓