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1.
云南松林施肥对防治纵坑切梢小蠹虫作用初探 总被引：1，自引：0，他引：1
１９９４年和１９９５年在玉溪市北城镇刺桐关办事处石狗头村，云南松纵坑切梢小蠹虫危害的云南松林中，进行了施肥试验，施肥后的云南松被害株率和蠹害指数平均下降２２．６９％和３３．７％，而未施肥的云南松被害株率和蠹害指数平均下降１１．７３％和１８．３％，被害株率和蠹害指数实际平均下降１０．９６％和１５．４％，试验证明，通过施肥，增强树势，能提高云南松对纵坑切梢小蠹虫危害的抵御能力，起到间接防虫的效果。 相似文献
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应用聚集信息素监测与防治纵坑切梢小蠹 总被引：7，自引：0，他引：7
监测和防治试验结果表明：最好的诱芯9诱集效果是对照诱集效果的7706．8倍，是饵木的20．49倍；效果中等的诱芯1的诱集量是对照的4288．4倍，是饵木的11．4倍；效果最差的诱芯5诱集量为对照的830倍，是饵木的2．19倍。这一结果肯定了聚集信息素诱虫灵敏度高、效果好的特性。同时虫口密度、有虫株率和梢被害率3项指标的减退率证实了应用聚集信息素防治纵坑切梢小蠹的效果显著可靠。其虫口密度减退率平均为94．35％，有虫株率减退率平均为87．7％，被害梢减退率为88．39％。 相似文献
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不同蠹害区的蠹害木清理试验 总被引：9，自引：2，他引：7
在松纵坑切梢小蠹的综合防治中，蠹害木是清理是一重要环节。依据在轻、中、重受害云南松林区进行的蠹害木清理试验结果，一般情况下，对轻度受害区即被害标率在１０％以下，蠹害指数在５以下，清理蠹害木应控制在１．００％，对中度受害区，即被害株率在１０％～５０％，蠹害指数在５～１５，清理蠹害木应控制在１０．００％左右，重度受害区，重度受害区，即被害株率在５０％以上，蠹害指数在１以上，清理蠹害木应控制在２０．００ 相似文献
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应用花绒寄甲防治松褐天牛 总被引：2，自引：0，他引：2
选取6个松褐天牛危害的马尾松林样地,释放寄生性天敌花绒寄甲的卵和成虫。通过调查天敌释放前后被害株数和单株虫口数2个指标对花绒寄甲的防治效果进行评价,同时,采用室内和林间罩网寄生试验相结合的方法分析花绒寄甲对松褐天牛幼虫的寄生情况。在释放花绒寄甲卵和成虫后对当年松褐天牛的寄生防治效果显示:在释放花绒寄甲卵的3个试验林中,平均株虫口校正减退率为48.54%,平均被害株校正减退率为63.07%;在释放花绒寄甲成虫的3个试验林中,平均株虫口校正减退率为47.00%,平均被害株校正减退率为68.00%,二者差异不显著。说明林间释放花绒寄甲卵和成虫均对松褐天牛有良好的控制效果。室内试验中,释放花绒寄甲卵和成虫后,不同胸径受害木段中松褐天牛幼虫被寄生的数量比例变化较大,5～8cm胸径的木段中寄生率最高,达72.41%,显著高于10～15cm和>18cm胸径木段的49.52%和49.06%;分别在5,7和9月释放花绒寄甲卵和成虫,寄生率分别为68.50%,21.63%和30.29%,5月份的寄生率显著高于7月和9月。利用花绒寄甲防治松褐天牛具有良好的控制效果,以5月份释放天敌效果最好,可在生产中推广应用。 相似文献
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１９９３￣１９９４年，对马尾松树进行调查研究后表明，１株１５年生松树针叶平均鲜重为２１１８ｇ，其外层１年生针叶占总重数６１％，内层２年生针叶占总重数３９％，１￣３轮枝叶占２５％，１￣４轮枝叶占７５％；针叶被害２５％时，留４轮枝叶可承受松毛虫１９条，是留３轮枝叶的２．４倍。 相似文献
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狗獾控制沙棘木蠹蛾的初步调查 总被引：5，自引：0，他引：5
沙棘木蠹蛾Holcocerus hippophaecolus Hua．Chou，Fang et Chen主要分布在内蒙古、辽宁、山西、陕西、宁夏、河北等地，发生面积13．3万hm^2，其中50％以上的受害沙棘林成片死亡。据在内蒙古鄂尔多斯市调查，沙棘木蠹蛾发生面积1．8万hm^2，发生率58．7％，平均有虫株率42％，平均虫口密度9头／株，最高可达118头／株。通过人工饲养和野外观察，对狗獾的生活习性及其林间控制沙棘木蠹蛾情况进行了调查研究。 相似文献
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释放花绒寄甲防治危害白蜡的云斑天牛 总被引：4，自引：0，他引：4
在地处黄河三角洲的山东省东营市和滨州市,选取8个受害严重的白蜡林作为试验样地,在云斑天牛幼虫期释放花绒寄甲卵和成虫,然后调查和统计天敌释放前后白蜡树的被害株率、天牛的株虫口数,计算出花绒寄甲对云斑天牛的防治效果.结果表明:林间释放花绒寄甲卵和成虫对云斑天牛均有良好的控制作用.在释放花绒寄甲卵的5个试验林中,释放后第2年的平均株虫口校正减退率为73.16％,平均被害株校正减退率为72.36％;在释放花绒寄甲成虫的3个试验林中,释放后第2年的平均株虫口校正减退率为77.20％,平均被害株校正减退率为69.68％.对释放花绒寄甲卵和成虫的防治效果进行比较表明,释放花绒寄甲成虫的防治效果略高于释放卵的林分,但二者差异不显著,说明在云斑天牛生物防治中,释放花绒寄甲2种虫态的天敌均不失为有效和良好的技术,而卵的成本低,值得在生产防治中大力推广应用. 相似文献
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澳大利亚杂交松在广西引种试验研究 总被引：1，自引：0，他引：1
澳大利亚杂交松(Pinus elliottii×Pinus caribaea)引种区域对比试验表明,杂交松能适应广西的自然条件,并表现出优良的速生丰产性状。杂交松的生长优于马尾松、湿地松和加勒比松,其平均公顷蓄积量分别比马尾松、湿地松和加勒比松大34.93%、82.44%和174.98%。杂交松年均树高和年均胸径生长量都超过了广西马尾松速丰林生长指标,适于在生产中推广。 相似文献
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《Scandinavian Journal of Forest Research》2012,27(1-4):349-357
The blister rust of two‐needle pines in Europe is caused by the rust fungus, Cronartium flaccidum (Alb. Schw.) Wint. There are two races of the fungus: One host‐alternating and another pine‐to‐pine race. The latter race is considered to be more common in northern Sweden. The impact of this rust on growth of Scots pine (Pinus sylvestris L.) was investigated in three selected stands in northern Sweden. Radial stem increment was reduced 40–70% by severe attacks and 20–40% by minor attacks. The reduction of stem volume growth was probably greater. The faster growing trees seemd to be more severely attacked. Trees growing on poor soils appeared to lose almost as much growth capacity from a minor attack as from a severe attack. 相似文献
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《林业研究》2019,(6)
Bark beetles Tomicus yunnanensis and T. minor are two important pests of Pinus yunnanensis and can cause massive death of pine trees. In this study, we examined several traits related to photosynthesis in P.yunnanensis and their relationship with antibiotic defense responses after joint attack by the two bark beetles at the shoot and the trunk stages. When shoots were attacked by the beetles, the abundance of chlorophylls, carotenoids, and the rates of net photosynthesis(Pn) and transpiration(E) decreased in needles, while the levels of superoxide dismutase and malondialdehyde remained unchanged in both needles and phloem. The activity of peroxidases also remained unchanged in needles, but increased in phloem.The activity of catalases increased in both needles and phloem. When trunks were attacked by the bark beetles,chlorophyll abundance, Pn, E, and antioxidative enzyme activities all declined, and the declines were more pronounced than in the attacked shoots. A decrease in protein concentrations was also observed in needles and phloem from the attacked pines. Attack on shoots by the bark beetles suppressed host defense and provided a favorable environment for larval growth and development, resulting in long-term decline of pine growth potential. The results suggest that attacks on trunks by beetles caused more severe damage to host trees than attacks on shoots. 相似文献
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Oleoresin flow is an important factor in the resistance of pines to attack by southern pine beetle, Dendroctonus frontalis Zimm., and its associated fungi. Abiotic factors, such as nutrient supply and water relations, have the potential to modify this plant-insect-fungus interaction; however, little is known of the effects of inoculation with beetle-associated fungi on oleoresin flow. We observed that constitutive and induced resin yield in loblolly pine, Pinus taeda L., were affected by either fungal inoculation (with the southern pine beetle-associated fungus Ophiostoma minus (Hedgcock) H. & P. Sydow) or silvicultural treatment. The effects of mass wounding (400 wounds m(-2)) and mass wounding and inoculation with O. minus were assessed by comparison with untreated (control) trees. The treatments were applied to trees in a 2 x 2 factorial combination of fertilizer and irrigation treatments. Fertilization did not significantly affect constitutive resin yield. Even as long as 105 days post-treatment, however, mass-inoculated trees produced higher induced resin yields than control or wounded-only trees, indicating a localized induced response to fungal inoculation. We noted no systemic induction of host defenses against fungal colonization. Although beetles attacking previously attacked trees face a greater resinous response from their host than beetles attacking trees that had not been previously attacked, the effect of an earlier attack may not last more than one flight season. Despite mass inoculations, O. minus did not kill the host trees, suggesting that this fungus is not a virulent plant pathogen. 相似文献
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Influence of ozone and nitrogen deposition on bark beetle activity under drought conditions 总被引：3，自引：0，他引：3
Michele Eatough Jones Timothy D. Paine Mark E. Fenn Mark A. Poth 《Forest Ecology and Management》2004,200(1-3):67-76
Four years of severe drought from 1999 through 2003 led to unprecedented bark beetle activity in ponderosa and Jeffrey pine in the San Bernardino and San Jacinto Mountains of southern California. Pines in the San Bernardino Mountains also were heavily impacted by ozone and nitrogenous pollutants originating from urban and agricultural areas in the Los Angeles basin. We studied bark beetle activity and bark beetle associated tree mortality in pines at two drought-impacted sites in the San Bernardino Mountains, one receiving high levels of atmospheric pollutants, and one with more moderate atmospheric input. We also investigated the effects of nitrogen addition treatments of 0, 50 and 150 kg N ha−1 year−1 at each site. Tree mortality and beetle activity were significantly higher at the high pollution site. Differences in beetle activity between sites were significantly associated with ozone injury to pines, while differences in tree mortality between sites were significantly associated with both ozone injury and fertilization level. Tree mortality was 9% higher and beetle activity 50% higher for unfertilized trees at the high pollution site compared to the low pollution site. Tree mortality increased 8% and beetle activity increased 20% under the highest rates of nitrogen additions at the low pollution site. The strong response in beetle activity to nitrogen additions at the low pollution site suggests that atmospheric nitrogen deposition increased tree susceptibility to beetle attack at the high deposition site. While drought conditions throughout the region were a major factor in decreased tree resistance, it appears that both ozone exposure and atmospheric nitrogen deposition further increased pine susceptibility to beetle attack. 相似文献
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In this study, the effect of pine mistletoe (Viscum album subsp. austriacum) on basal area increment of Crimean pine and Scots pine was investigated. Dendrochronological data were collected from 223 (71 uninfected and 152 infected) Crimean pines and 195 (77 uninfected and 118 infected) Scots pines located in Kastamonu province of Turkey in 2014. Infected sample trees were classified as light, moderate or severe infection levels. Growth trends and basal area increment loses were compared between uninfected and infected trees for the periods of the last 10, 20 and 30 years. In addition, infection status of forest stands was investigated using temporary sample plots; 27 plots in Crimean pine stands and 26 plots in Scots pine. Results demonstrated that basal area increments were negatively affected by pine mistletoe for both species. Mean basal area increment losses of infected trees for the last decade were determined as 24% for Scots pine and 26% for Crimean pine. Basal area increment losses varied by infection levels (light, moderate and severe) as follows: 25%, 20% and 28% for Scots pines and 20%, 32% and 9% for Crimean pines. Scots pine stands were more severely infected by pine mistletoe than Crimean pine stands. There were negative correlations between number of infected trees and stand density for both species, while positive correlation was detected between the number of infected trees and mean diameter for Scots pine. The results of this study indicate that the pine mistletoe infection has negative effect on radial growth of Scots pine and Crimean pine trees. The results can be an important contribution to the forest management and protection activities in mistletoe-infected stands. 相似文献
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Curiel Yuste J Konôpka B Janssens IA Coenen K Xiao CW Ceulemans R 《Tree physiology》2005,25(6):701-712
Standing biomass, net primary production (NPP) and soil carbon (C) pools were studied in a 67-year-old pedunculate oak (Quercus robur L.) stand and a neighboring 74-year- old Scots pine (Pinus sylvestris L.) stand in the Belgian Campine region. Despite a 14% lower tree density and a lower tree height in the oak stand, standing biomass was slightly higher than in the pine stand (177 and 169 Mg ha(-1) in oaks and pines, respectively), indicating that individual oak trees contained more biomass than pine trees of similar diameter. Moreover, NPP in the oak stand was more than double that in the pine stand (17.7 and 8.1 Mg ha(-1) year(-1), respectively). Several observations indicated that soil organic matter accumulated at higher rates under pines than under oaks. We therefore hypothesized that the pines were exhibiting an age-related decline in productivity due to nutrient limitation. The poor decomposability of pine litter resulted in the observed accumulation of organic matter. The subsequent immobilization of nutrients in the organic matter, combined with the already nutrient-poor soil conditions, resulted in a decrease in total NPP over time, as well as in a substantial shift in the allocation of NPP toward fine roots. In the oak stand, litter is less recalcitrant to decay and soil acidity is less severe; hence, organic matter does not accumulate and nutrients are recycled. This probably explains why NPP was much higher in the oaks than in the pines and why only a small proportion of NPP was allocated to oak fine roots. 相似文献
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Takefumi Ikeda 《Journal of Forest Research》1996,1(4):223-226
The effect of water-stress conditioning on water relations and histological features ofPinus thunbergii Parl. inoculated with avirulent isolate ofBursaphelenchus xylophilus (Steiner and Buhrer) Nickle, pine wood nematode, were investigated. Pines were kept under 8 days cycle of severe water stress.
One-half of the water-stressed pines died as a result of infection by avirulent pine wood nematode and water stress tended
to induce increased susceptibility and/or decreased resistance of pines to avirulent pine wood nematode. In dead pines, the
water conducting function of xylem was lost, and all of the parenchyma cells died. In surviving pines, the xylem hydraulic
conductivity and the xylem water content were significantly reduced (12 to 23% and 77 to 83%, respectively) compared to controls.
Safranin dye perfusion of excised axis stem segments indicated that the water conductance was limited to the very narrow peripheral
area of xylem. Embolism caused by cavitation in the tracheids occurred in the central part of xylem and in that dysfunctional
region of the xylem the axial parenchyma cells surrounding the epithelial cells, and ray parenchyma cells partly degenerated
but the epithelial cells survived. The disruption of tracheid shape observed in surviving pines indicates that avirulent pine
wood nematode temporarily disturbed cell division of the cambium. Considering the differences in responses between dead pines
and surviving pines after inoculation with avirulent pine wood nematode, the death of water-stressed pines apparently resulted
from death of cells, in particular the vascular cambium and the loss of xylem hydraulic function by cavitation. 相似文献