Bt乳剂防治油松种实害虫试验报告

我省油松种实害虫包括油松球果小卷蛾、球果梢斑螟、微红梢斑螟、松梢小卷蛾、松实小卷蛾、一点实小卷蛾及中华松果长蝽、球果窃蠹、球果瘿蚊等种类,油松球果小卷蛾占总虫数的75％以上,是优势虫种,以此虫为靶子害虫进行防治,可以取得事半功倍的效果。Bt 乳剂属苏云金杆菌(Bacillus thu-ringinsis),已广泛应用于农业害虫和果树害虫的防治。为探索其防治油松种实害虫的     

红松种实害虫生物学特性的研究

红松种实害虫危害红松的球果及种子,造成种子产量下降、质量低劣,严重的可导致红松种子绝产。在黑龙江省牡丹江林区,直接危害红松种实的害虫主要有赤松梢斑螟、冷杉梢斑螟、松梢螟、红松球果种蝇、红松球果种小蜂等。其中冷杉梢斑螟为原始红松林果梢的重要害虫,赤松梢斑螟主要以幼虫危害红松幼树的球果、嫩梢及干部,是该地区危害红松种实的主要害虫。     

马尾松枝梢害虫防治研究进展情况

马尾松枝梢害虫主要包括微红梢斑螟、松实小卷蛾、油松球果小卷蛾、松果梢斑螟等。在春季蛀食幼树嫩梢髓部,被害梢弯曲枯死,影响幼树高生长和材质。近年来生产上应用林业措施、化学和生物防治等综合治理来抑制害虫数量。具体方法是剪除被害梢果,营造混交林,幼虫孵化盛期喷洒氯氰菊酯和氧化乐果混合剂,卵期释放赤眼蜂。防治微红梢斑螟还可在成虫期设置性诱剂(Z_(11-16):AC、Z_(11-16):ALD、Z_9E_(11-14):AC)诱捕器诱杀。     

云杉梢斑螟防治

<正>云杉梢斑螟是云杉的主要枝梢害虫,也危害油松。以幼虫危害云杉新梢嫩叶、花序及球果,使新梢不能抽出,或新梢弯曲下垂干枯,或形成虫瘿。林木连年受害后树冠秃顶,枯梢密布,高生长受到抑制,植株呈灌丛状,严重影响林木的正常生长。从本世纪初开始,云杉梢斑螟在甘肃中南部地区大范围发生,造成经济损失上亿元,成为许多地方预防除治的重点对象。     

油松球果螟的初步研究

一、寄主及危害油松球果螟(Dioryctria mendacella Stgr。)是章古台地区油松、赤松、樟子松林内的主要害虫之一。油松球果螟(以下简称球果螟),幼虫钻蛀球果和嫩梢,个别植株一年生梢几乎100%受害,弄得松树披头散发,影响树木生长,尤其主梢受害,造成嫩梢丛生,形成分叉     

松果梢斑螟生活习性及防治方法的研究

在兴城市油松种子园中,从雌球花出现到球果采收,松果梢斑螟危害2年生球果,同时也危害1年生球果,危害率占昆虫总危害率的87.36%.通过对松果梢斑螟生活习性、危害关系及防治方法的研究,对其进行适时适药防治,可使种子园产量提高29.2%.     

松果梢斑螟生活习性及防治方法的研究

在兴城市油松种子园中，从雌球花出现到球果采收，松果梢斑螟危害2年生球果，同时也危害1年生球果，危害率占昆虫总危害率的87．36％。通过对松果梢斑螟生活习性、危害关系及防治方法的研究，对其进行适时适药防治，可使种子园产量提高29．2％。     

松果梢斑螟成虫的寄主选择

在松果梢斑螟成虫产卵期,采用顶空吸附法和CC-:MS分析,研究虫害后油松球果萜类挥发物成分的变化.油松虫害球果(枝)单萜挥发物的释放呈现昼夜节律,并且特异性挥发组分为1R-(+)-α-蒎烯、β-香叶烯和D-柠檬烯.梢斑螟成虫为夜出性害虫,因此产卵期晚上的球果(枝)挥发物更有意义.油松和华山松球果的触角电位(EAG)测试表明:虫害球果与健康球果相比,梢斑螟(雌雄蛾)对油松虫害球果的EAG反应更明显;而对华山松虫害球果和健康球果的EAG反应差异不明显.Y-型嗅觉仪的趋向试验表明:雌成虫的寄主选择性明显高于雄虫,油松球果提取液的引诱作用高于华山松球果,而当年生针叶提取液、虫害球果及其提取液挥发物对雌成虫的引诱作用均高于健康球果;挥发物标准品测试显示,1R-(+)-β-蒎烯、β-香叶烯和D-柠檬烯组合具有明显的引诱作用.虫害油松球果及其提取液可显著刺激雌成虫产卵,表明油松虫害球果提取液组分中存在着雌成虫的产卵刺激物;华山松球果提取液的存在明显抑制了雌虫在油松虫害球果提取液滤纸上的产卵,表明华山松球果提取液中可能有产卵拒避剂.     

藏东南主要针叶林球果害虫种类及危害情况调查

2015—2017年,采用野外实地调查与室内解剖、饲养相结合的方法对藏东南主要针叶林球果害虫及其危害特征进行了研究。结果表明:高山松Pinus densata林球果害虫为赤松梢斑螟Dioryctria sylvestrella,林芝云杉Picea likiangensis var.linzhiensis林球果害虫为冷杉梢斑螟D.abietella,急尖长苞冷杉Abies georgei var.smithii林球果害虫为球果螟D.sp.、球果花蝇Lasiomma sp.和大痣小蜂Megastigmus sp.,害虫区系与东北针叶林害虫区系类似。高山松天然林球果的被害率为9.23%,人工林被害率为23.33%,1个球果1头虫;色季拉山林芝云杉林球果被害率为69.76%,波密县岗乡球果被害率为41.55%,1个球果1～6头虫不等;急尖长苞冷杉林球果总被害率为19.18%,多数情况1个球果1种害虫危害,少数情况1个球果2种害虫同时危害。     

泊江省蛀食松梢球果的蛾类害虫

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。     

针叶小爪螨——寄主植物——芬兰钝绥螨相互关系的研究Ⅱ.挥发性物质在寄主植物——针叶小爪螨——芬兰钝绥螨之间的作用

用气相色谱 -质谱联用仪分析了板栗健康叶片、被针叶小爪螨危害过 (除去叶螨 )的叶片和被该叶螨危害并带有该叶螨的叶片挥发性物质的成分和相对含量。在受害和未受害叶片中 ,石竹烯和α 法尼烯均占较大的比例。石竹烯在受害叶中的峰值增高 ;而α 法尼烯在无叶螨的受害叶中的峰值增高 ;1 辛烯在未受害叶片中未检测到 ,但在受害的叶片中则含量均较高 ,尤其有叶螨的受害叶片较无叶螨的受害叶片 1 辛烯的峰值显著增高 ;苯甲酸乙酯在有叶螨的受害叶片中较其余 2种也显著增高 ;3,7,11 三甲基 1 6 10 十二碳三烯 3 醇以有螨的受害叶中含量最高 ,无叶螨的受害叶次之 ,未受害叶含量极微 ,几乎检测不到 ;但 4 溴 2 戊烯却呈现相反的趋势 ,在未受害叶中的含量显著高于受害叶。根据生物测试结果做出如下推断 :叶片受害后 ,挥发性物质的种类和含量发生了变化 ,改变了原来寄主植物气味的化学指纹图 ,使针叶小爪螨在识别寄主植物时遇到困难 ,甚至产生了忌避作用而从受害叶转移到未受害叶上。同时这些物质对引诱芬兰钝绥螨起着重要的引诱作用     

木蠹象对受疱锈菌侵染华山松树皮挥发物的EAG和行为反应

采用触角电位仪和"Y"型嗅觉仪分别研究了茶蔗生柱锈菌锈孢子、感疱锈病树皮、华山松健康树皮挥发性成分对华山松木蠹象的触角电生理和引诱活性.羽化3 d的木蠹象对3种挥发性成分在各浓度下都有明显的EAG反应,锈孢子的EAG反应值最大,健康树皮次之,感病树皮最小,且明显小于前二者.同时,嗅觉生测结果证明,锈孢子挥发性成分对木蠹象的引诱活性最低,平均引诱率不超过20%;同样,感病树皮挥发性成分除浓度为1:15外,其余引诱率都低于35%,二者对该虫总体表现出驱避活性;而健康树皮挥发性成分则有明显的引诱活性.EAG反应值与行为反应的趋向率具有一致性.     

Carbon and nitrogen cycling immediately following bark beetle outbreaks in southwestern ponderosa pine forests

Bark beetle infestation is a well-known cause of historical low-level disturbance in southwestern ponderosa pine forests, but recent fire exclusion and increased tree densities have enabled large-scale bark beetle outbreaks with unknown consequences for ecosystem function. Uninfested and beetle-infested plots (n = 10 pairs of plots on two aspects) of ponderosa pine were compared over one growing season in the Sierra Ancha Experimental Forest, AZ to determine whether infestation was correlated with differences in carbon (C) and nitrogen (N) pools and fluxes in aboveground biomass and soils. Infested plots had at least 80% of the overstory ponderosa pine trees attacked by bark beetles within 2 years of our measurements. Both uninfested and infested plots stored ∼9 kg C m⁻² in aboveground tree biomass, but infested plots held 60% of this aboveground tree biomass in dead trees, compared to 5% in uninfested plots. We hypothesized that decreased belowground C allocation following beetle-induced tree mortality would alter soil respiration rates, but this hypothesis was not supported; throughout the growing season, soil respiration in infested plots was similar to uninfested plots. In contrast, several results supported the hypothesis that premature needlefall from infested trees provided a pulse of low C:N needlefall that altered soil N cycling. The C:N mass ratio of pine needlefall in infested plots (∼45) was lower than uninfested plots (∼95) throughout the growing season. Mineral soils from infested plots had greater laboratory net nitrification rates and field resin bag ammonium accumulation than uninfested plots. As bark beetle outbreaks become increasingly prevalent in western landscapes, longer-term biogeochemical studies on interactions with other disturbances (e.g. fire, harvesting, etc.) will be required to predict changes in ecosystem structure and function.     

Stand characteristics and downed woody debris accumulations associated with a mountain pine beetle (Dendroctonus ponderosae Hopkins) outbreak in Colorado

Lodgepole pine (Pinus contorta Dougl. ex Loud.)-dominated ecosystems in north-central Colorado are undergoing rapid and drastic changes associated with overstory tree mortality from a current mountain pine beetle (Dendroctonus ponderosae Hopkins) outbreak. To characterize stand characteristics and downed woody debris loads during the first 7 years of the outbreak, 221 plots (0.02 ha) were randomly established in infested and uninfested stands distributed across the Arapaho National Forest, Colorado. Mountain pine beetle initially attacked stands with higher lodgepole pine basal area, and lower density and basal area of Engelmann spruce (Picea engelmannii [Parry]), and subalpine fir (Abies lasiocarpa (Hook.) Nutt. var. lasiocarpa) compared to uninfested plots. Mountain pine beetle-affected stands had reduced total and lodgepole pine stocking and quadratic mean diameter. The density and basal area of live overstory lodgepole declined by 62% and 71% in infested plots, respectively. The mean diameter of live lodgepole pine was 53% lower than pre-outbreak in infested plots. Downed woody debris loads did not differ between uninfested plots and plots currently infested at the time of sampling to 3 or 4–7 years after initial infestation, but the projected downed coarse wood accumulations when 80% of the mountain pine beetle-killed trees fall indicated a fourfold increase. Depth of the litter layer and maximum height of grass and herbaceous vegetation were greater 4–7 years after initial infestation compared to uninfested plots, though understory plant percent cover was not different. Seedling and sapling density of all species combined was higher in uninfested plots but there was no difference between infested and uninfested plots for lodgepole pine alone. For trees ≥2.5 cm in diameter at breast height, the density of live lodgepole pine trees in mountain pine beetle-affected stands was higher than Engelmann spruce, subalpine fir, and aspen, (Populus tremuloides Michx.), in diameter classes comprised of trees from 2.5 cm to 30 cm in diameter, suggesting that lodgepole pine will remain as a dominant overstory tree after the bark beetle outbreak.     

Amino nitrogen and phenolic constituents of bark of American beech,Fagus grandifolia,and infestation by beech scale,Cryptococcus fagisuga

Concentrations of amino acids, total amino nitrogen, and phenols, ratio of phenol to amino nitrogen, and pH in the bark of American beech, Fagus grandifolia, were determined to see if these chemical constituents were correlated with susceptibility of trees to infestation by the beech scale, Cryptococcus fagisuga. The relationship of these bark constituents with scale infestation levels (none, light, and moderate), tree size (large vs. small trees), and bark shading was determined. Levels of some individual amino acids and total amino acid content in moderately infested trees were significantly higher than in uninfested trees. Large uninfested beech trees, which tend to be more readily infested by scale, had significantly higher concentrations of aspartic acid. Concentrations of phenol in the outer bark of both infested and uninfested trees were significantly higher than in the inner bark. However in bark infected by Nectria, phenol levels in the inner bark were significantly higher than in the outer bark.     

针叶小爪螨-寄主植物-芬兰钝绥螨相互关系的研究Ⅰ.针叶小爪螨对寄主植物和芬兰钝绥螨对猎物的嗅觉反应

用Y形嗅觉仪测定了针叶小爪螨对其寄主植物 ,芬兰钝绥螨对针叶小爪螨的选择行为。结果表明 :针叶小爪螨对未受害的麻栎叶、栓皮栎叶和板栗叶都表现出较强的趋性 ,对槲树叶虽然也有趋性 ,但趋向程度不如前三者强 ,而松针和云杉对其有较强的忌避作用 ;用同一寄主植物的未受害叶片和除螨受害叶片测定时 ,则明显趋向于未受害叶片 ;而用同一寄主植物的除螨受害叶片和带螨受害叶片测定时 ,则喜欢选择带螨受害叶片。寄主植物受害与否以及有无叶螨存在 ,显著影响芬兰钝绥螨的趋性。芬兰钝绥螨对未受叶螨危害和受叶螨危害的寄主植物叶片均有趋性 ,但对后者的趋性反应更为强烈 ,对有叶螨的危害叶片和无叶螨的危害叶片的趋性反应之间也存在显著差异     

Green spruce aphid infestations cause larger growth reductions to Sitka spruce under shade

Light availability and infestation by the green spruce aphid (Elatobium abietinum) are key factors affecting the growth of Sitka spruce (Picea sitchensis) seedlings under a mature tree canopy, but their combined effect on seedling growth has not previously been quantified. A controlled outdoor experiment in which light levels (high light (HL): 100%, intermediate light (IL): 24%) and aphid infestation (absence/presence) were manipulated was conducted over 2 years to look at the effects on seedling growth and biomass distribution patterns. Aphid population assessments showed a significantly increased population density under IL, with three to four times higher cumulative aphid densities than that under HL. Defoliation rates of infested seedlings were directly related to aphid density. Total seedling biomass was strongly reduced in IL, and aphid infestation caused additional reductions in the biomass of particular components of the seedlings. Dry weight (DW) of older (≥1-year-old) needles in infested trees was significantly decreased in both years. Total root DW at the end of the second year was significantly affected by aphid infestation, and the reduction (14-18%) was similar in IL and HL treatments despite large differences in aphid density. Biomass distribution patterns in infested trees were similar to that of uninfested trees within each light treatment, indicating that the relative decreases in root biomass were accompanied by similar reductions in distribution to the above-ground parts of the seedlings. Leader extension growth of infested seedlings was reduced by 15-17% compared with uninfested seedlings under IL, whereas only a 2-3% reduction in leader extension of infested seedlings under HL was observed. The results showed that the response of seedlings to E. abietinum were primarily dependent on the light environment. The significant reduction caused by aphids on the total DW of older needles and roots, and on leader extension growth, does suggest the potential for effects to accumulate over time.     

绿竹链蚧危害对绿竹叶绿素及光合作用的影响

研究了绿竹链蚧不同危害程度对绿竹光合作用的影响。结果表明:与未受害比,轻度、中度、重度受害绿竹的SPDA值分别减少4.6%,12.4%,22.4%;净光合速率分别减少7.79%,16.39%,29.38%;暗呼吸速率分别提高了5.49%,26.67%,-7.39%;光呼吸速率分别提高了6.60%,30.08%,-11.56%;CO2补偿点分别提高1.15,1.48,2.04倍。不同受害程度对绿竹光合作用各项指标的影响均达极显著或显著水平。     

Comparison of host volatiles under different physiological states and electroantennogram responses of Semanotus bifasciatus （Motschulsky） to these volatiles

Based on an analytical TCT-GC/MS method, volatile compounds of branches of Platycladus orientalis under three physiological states （healthy, weak and baited trees） were analyzed. The results showed that α-pinene, β-phellandrene, 3-careen, limonene and thujopsene were released under all three physiological states. There were other kinds of volatiles released from branches of weak P. orientalis trees, such as camphene, γ-terpinene, （＋）-4-carene and cedrene, but these four volatiles compounds were not released from the branches of healthy P. orientalis. Volatile components from the physically damaged branches of P. orientalis had changed. β-terpinene, mycrene, isocaryophillene and caryophyllene were identified in both healthy and weak branches of P. orientalis. Only cedrene was identified in the baited wood. Electroantennogram （EAG） tests were conducted with nine volatile compounds from the branches of P. orientalis. Antennnae of male and female Semanotus bifasciatus （Motschulsky） were highly sensitive to these nine volatile compounds. Cedrene elicited the strongest response, whereas β-terpinene the lowest. Males and females showed no signifi-cant difference in their EAG responses to the nine volatile compounds.