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1.
落叶松毛虫(Dendrolimus superans)又称西伯利亚松毛虫,隶属鳞翅目(Lepidoptera)枯叶蛾科(Lasiocampidae).国内分布于北京、东北、内蒙古、新疆北部,是我国东北林区的重要害虫,除危害落叶松(Larix spp.)外,也危害红松(Pinus koraiensis)、油松(P.tabulaeformis)、樟子松(P.sylvestris var.mongolica)、云杉(Picea spp.)、冷杉(Abies spp.)等主要北方针叶树种.目前,有关落叶松毛虫的研究主要集中在发生规律及预测预报、对挥发物质的行为反应及药效防治试验等方面的研究,而有关杀虫剂对落叶松毛虫的毒理机制方面的研究未见报道.  相似文献   

2.
1 引言二针松疱锈病是由松芍柱锈菌(Cronartium flaccidum)引起的。在栽植欧洲赤松(Pinus Sylvestris L.)、海岸松(P.pinaster Ait.)、奥地利松、欧洲黑松(P.nigra Arnold)、意大利五针松(P.pinea L.)、欧洲山松(P.mugo Turra)、阿勒颇松(P.halpensisMill.)、地中海松(P.brutia Tenn.)的一些欧洲国家蔓延。在意大利中部和南部,20年来,该病在人工林和二针松苗圃中大肆流行,严重危害。本文主要介绍松芍柱锈菌的生物学研究概  相似文献   

3.
引言据报道,芽枝霉菌(Cladosporium humileJ.J.Davis)是引起北方邦、喜马偕尔邦、查谟和克什米尔等地区绿毛杨(Populus cil-iata Wall.)、黑杨(P.nigra Linn.)和银白杨(P.alba Linn.)苗圃和人工林提早落  相似文献   

4.
锈寄生菌对杨柴锈病菌的寄生及控病作用   总被引:4,自引:0,他引:4       下载免费PDF全文
杨柴锈病(Uromyceshedysari-mongoliciYuan.)是毛乌素沙地先锋固沙树种杨柴(HedysarummongolicumTurcz.)的重要病害。由于受其危害,使杨柴提早落叶、枝条枯死,严重影响了杨柴的生长发育,给治沙造林生产带来很大损失。锈寄生菌(Sphaerellopsisfilum(Biv.-Bern.exFr.)Sutto...  相似文献   

5.
普隆斯基(Plonski 1956,1960)为加拿大安大略省的一些主要用材树种:黑云杉(Picea mariana[Mill]B.S.P.)、短叶松(Pinus banksiana. Lainb.)、白杨(Populus tremuloides. Michx.)、白桦(Betula papyrifera. Marsh.)、  相似文献   

6.
普隆斯基(Plonski 1956,1960)为加拿大安大略省的一些主要用材树种:黑云杉(Piceamariana[Mill]B.S.P.)、短叶松(Pinus banksiana.Lamb.)、白杨(Populus tremuloides.Michx.)、白桦(Betula papyrifera.Marsh.)、美国白松(Pinus strobus.L.)、美加红松(Pinus resinosa.Ait.)以及耐荫阔叶树等编绘  相似文献   

7.
梳角窃蠹的防治研究   总被引:2,自引:0,他引:2       下载免费PDF全文
梳角窃蠹 ( Ptilinus fuscus Geoffroy) ,亦称梳栉窃蠹 ,属鞘翅目 ( Coleopptera) ,窃蠹科( Anobiidae)。嗜食多种杨 ( Populus spp.)、柳 ( salix spp.)及白榆 ( Ulmus pumila L.)的干材 ,尤以青杨 ( P.cathayana Rehd.)受害最重 ,除钻蛀居室木材外 ,还能寄生于活立木的枯朽枝、干部 ;如云杉 ( Picea spp.)木与杨、柳木混用时 ,也能轻度危害云杉木。据报道国外分布于欧洲、埃及、叙利亚 ,国内分布于青海、辽宁[1] 、甘肃 (兰州、白银、临夏、定西、天水、平凉、庆阳、陇南等8地 (州、市 )的 46县 (市、区 ) ) ,是甘肃省房屋木材构件杨…  相似文献   

8.
为防控外来植物的扩散入侵,于2012年4月—2013年4月共5次全面调查了舟山岛及其附近岛屿的植物种类组成和外来植物分布状况,同时辅以典型抽样法,并结合历史资料,归纳整理了舟山岛不同历史时期的外来植物名录,共计48科106属145种;在此基础上对外来植物进行了风险评估并探讨了部分重要物种的入侵性。其中加拿大一枝黄花(Solidago canadensis Linn.)、喜旱莲子草(Alternanthera philoxeroides(Mart.)Griseb.)对舟山岛入侵危害最大,应为今后防治的重点;藿香蓟(Ageratum conyzoides Sieber ex Steud.)、豚草(Ambrosia artemisiifolia Linn.)等著名外来恶性杂草近20 a来并没有明显的扩散,危害等级为中等;新记录外来植物野莴苣(Lactuca serriola Linn.)的扩散、危害风险值得关注和警惕;水生生境外来植物中,凤眼蓝(Eichhornia crassipes(Mart.)Solms)风险等级低,而互花米草(Spartina alterniflora Hubb.)、大米草(S.anglica Lois.)风险等级高,应加强监控;栽培植物西欧蝇子草(Silene gallica Linn.)首现逸为野生,生长扩散需要跟踪监控。  相似文献   

9.
<正> 松属(Pinus)的针叶锈病系由无柄锈科鞘锈属的真菌(Coleosporium sp.)所引起。在我国,已经鉴定下来的鞘锈属的种有5个:一枝黄花鞘锈菌[Coleosporium solidaginies(Schw.)Thum.],侵染云南松(P.yunnanensis)和马尾松(P.massoniana);紫菀鞘锈菌[Col.asterum(Diet.)Syd.],侵染台湾松(P.taiwanensis)等;千里光鞘锈菌[Col.senecionis(Pers.) Fr.],侵染云南松;白头翁鞘锈菌[Col.  相似文献   

10.
森林病害 牡丹红斑病病原菌的研究(季延平,等.<山东林业科技>,2001,1:21-22.) 危害橡胶木的真菌和昆虫(邢嘉琪.<林业科学研究>,2001,2:230-235.) 梨锈病发生规律及药剂防治技术研究(李光武,等.<烟台果树>,2001,2:11-12.) 昆明地区香石竹病毒病及综合防治研究(蔡红,等.<云南农业大学学报>,2001,1:18-19.) E26防治植物根癌病的效果及其稳定性初步研究(梁志宏,等.<中国农业大学学报>,2001,1:91-95.)  相似文献   

11.
对1984年种植在广西和浙江的22个种源的火炬松及在浙江的8个种源的湿地松的木材密度和管胞长度进行了测定和分析。结果表明,两个树种的木材密度和管胞长度在种源间和种源内单株间均表现出显著差异,但株间差异较种源间差异显著得多。不同地区火炬松的差异较之同一地区不同种源间的差异更为显著。种源、地区的交互作用对火炬松的木材密度和管胞长度都表现出显著影响,种源和单株的交互作用对两个树种的木材密度也有显著影响。两个树种的木材材性与年轮宽度之间没有显著的相关关系。与马尾松和早期引种的火炬松、湿地松比较表明,用新引进的材料可选育出木材材质更为优良的品种。  相似文献   

12.
Cultural factors affecting in vitro shoot and subsequent plantlet formation of slash pine (Pinus elliotti Engelm.) cotyledons were investigated. Basal media composition, N6-benzylaminopurine (BAP) concentration and exposure time significantly influenced bud induction in cotyledons cultured under a continuous photoperiod of 35–40 mol m–2 s–1 at 24 ± 1 °C. The largest number of adventitious shoots was obtained after 28 days exposure to 66 M BAP-supplemented modified Gresshoff and Doy 1 (GD1) medium. Relatively high frequencies of large shoots were obtained after a 14-day exposure to 22 M BAP-supplemented Brown and Lawrence (BL) or 66 M BAP-supplemented GD1. Adventitious shoots derived from 21- or 28-day exposures to BAP developed more slowly and were smaller in size than those derived from a 14-day exposure to the cytokinin. Shoot differentiation and subsequent growth were also influenced by basal media, media concentration, and presence of activated charcoal in the medium. The percentage of cotyledons forming shoots was highest on half-strength GD1 medium containing activated charcoal. Rooting was achieved in vitro under a continuous photoperiod of 60–70 mol M–2 S–1. Roots were formed when excised shoots were planted on GD 1/2 medium supplemented with 2.68 M 1–1 a-napthaleneacetic acid (NAA) with or without BAP for 14 days. The proposed technique of slash pine propagation using cotyledon explants can produce up to 100 seedlings per embryo.  相似文献   

13.
Reinforcement of skid trails with slash has been shown to reduce soil disturbances, but there have not been any studies documenting the mitigating effects following traffic of harvest equipment traffic on steep mountainous skid trails. The objective of this study was to quantify potentially mitigating effects of slash cover on soil compaction and rutting on skid trails in mountainous hardwood forests. The effects of the placement of no slash (bare soil), light density slash (7.5 kg m?2) and heavy density slash (17.5 kg m?2) in a skid trail following one, five, and nine machine passes on both gentle slopes <20% and steep slopes >20% in a downhill skidding operation by a steel-tracked skidder were studied. Bulk density and rut depth increased following harvest equipment traffic on both slope gradients. Compared to bare soils, soil bulk density was not significantly reduced by light slash density; however, soil bulk density was significantly reduced by heavy slash up to five machine passes on steep slopes. Light and heavy slash significantly reduced rut depth in both slope classes. The study revealed a high protective role of slash, particularly on steep skid trails. However, benefits of slash to mitigate soil compaction were limited to five passes, after which the slash deteriorated and only provided benefits against rutting.  相似文献   

14.
Incorporation of forest slash during stand establishment is proposed as a means of increasing soil carbon and nutrient stocks. If effective, the increased soil carbon and nutrient status may result in increased aboveground tree growth. Eight years after study installation, the impact of forest slash incorporation into the soil on soil carbon and nutrient stocks, foliar nutrients and loblolly pine growth are examined on mineral and organic sites on the North Carolina Lower Coastal Plain. Treatments include leaving forest slash on the surface and flat planting (control); V-shear and bedding (conventional), mulch forest slash followed by bedding (strip mulch) and mulch forest slash and till into the soil followed by bedding (strip mulch till). After eight years, mulching and/or tillage did not have a significant impact (p > 0.05) on soil bulk density or soil chemical properties (pH, cation exchange capacity, soil nutrients). Additionally, neither tree foliar nutrients nor stand volume were significantly impacted. However, significant effects were observed for soil phosphorus contents and stand volume between the control plots and the other treatment plots. For example, the mean stand volumes on the mineral site were 24.49 ± 1.28, 38.16 ± 2.90, 44.59 ± 3.07 and 46.96 ± 2.74 m3 ha−1 for the control, conventional, strip mulch and strip mulch till plots. These observations are more likely due to the effect of bedding rather than mulching or tillage of the forest slash. These results are consistent for the mineral and the organic sites. Considering the greater expense to install the mulch and tillage treatments, the lack of a treatment effect on soil carbon and nutrient stocks and tree growth does not justify these treatments on these sites.  相似文献   

15.
利用热脉冲技术对雷州半岛25年生加勒比松人工林旱季 (2000年10月至2001年2月)树干液流特征、耗水及环境因子的关系进行研究.结果表明:加勒比松边材不同位点的液流密度由外到内呈低-高-低的态势;观测期间林分日液流密度变幅为411~4 120 L·m-2·d-1,日平均液流密度为2 084 L·m-2·d-1;旱季无雨时,加勒比松日液流密度与太阳辐射、饱和蒸汽压差、气温及湿度相关性显著;有雨时,加勒比松日液流密度仅与饱和蒸汽压及湿度相关性显著;单株日耗水量变幅为6.4~169.5 L,日平均耗水量为55.5 L,林分日耗水量变幅为0.35~3.52 mm·d-1,日均耗水量为1.71 mm·d-1,旱季总耗水量为257.7 mm,占同期降水量的72.3%.  相似文献   

16.
Measurements of pH were carried out at two experimental sites in Sweden before and after clear-felling. At eleven sites, pH, cation-exchange capacity, base saturation and exchangeable hydrogen ions were compared in clear-felled areas where slash was left and removed, respectively. It is shown that pH increases significantly after clear-felling. The increase is larger than can be explained by the release of basic cations in connection with decomposition of slash and humus. The increase in pH is less in a clear-felled area when the slash is removed than when it is left. There is a decrease in exchangeable Ca2+, Mg2+ and Mn2+ and an increase in H+ and Al3+. There is a decrease in base saturation of about 80%.  相似文献   

17.
通过对江西萧氏松茎象发生林区420株湿地松的调查和分析得出,萧氏松茎象防治指标(CT)为1.2头/株或65%的有虫株率。  相似文献   

18.
选择4年生湿地松优良家系试验林,通过测土配方施肥,研究其对湿地松生长与叶片、枝条养分含量及其土壤肥力的影响。结果表明:施肥后第2年,土壤全P含量与湿地松树高及胸径生长呈现极显著正相关,其数学模型分别为:y=-5.944 4 x+1.318 9、y=-7.500 0 x+2.700 0;施肥后土壤中速效K含量与叶片中全K含量呈现极显著正相关,其数学模型为:y=0.010 8 x-0.163 3;速效K含量与湿地松树高及胸径生长,其数学模型分别为:y=-0.032 8 x+1.513 3、y=-0.047 4 x+3.002 9;土壤中全N增长与湿地松叶片全N含量增长均呈现显著正相关,其数学模型为:y=7.016 1 x+0.162 1。湿地松平均树高与胸径相较于未施肥的对照组增幅分别达11%与13%以上,其差异达到了极显著水平。  相似文献   

19.
Research reported here has evaluated interactions of factors limiting the biological potential of slash pine (Pinus elliottii var. elliottii Engelm.) and loblolly pine (P. Taeda L.). Water and nutrients were manipulated by irrigation, weed control, and intensive fertilization. Genetic factors were incorporated as (1) improved loblolly seedlings from a commercial clonal seed orchard and (2) slash seedlings from four fast-growing, open-pollinated seed-orchard clones. Three replications of a 2 × 2 × 2 factorial experiment were established on a Typic Haplaquod soil in northern Florida using four cultural treatments: no treatment (F0H0); weed control (F0H1); fertilizer (F1F0); and combination of weed control and fertilizer (F1H1) for each species. During the first year there were large, sustained responses to all cultural practices. Loblolly and slash pine showed similar growth responses and had a lengthened growing season (60–100 days). Slash pine growth was superior to that of loblolly. Growth responses observed during the first year continued. After 4 years, irrigation had no measurable effect on tree growth. Both pine species responded equally to F1H0 and F0H1, but slash retained a slight edge. Extra nutrients]available via fertilizer, reduced competition, or additional rooting space, increased slash-pine volume index from an average of 2.0 m3 ha−1 (F0H0) to 11.90 and 13.59 m3 ha−1 (F0H1 and F1H0, respectively). The F1H1 treatment produced the largest slash-pine response, diameter at breast height (Dbh) averaged 9.84 cm, height reached 5.02 m, and volume index rose to about 22.94 m3 ha−1. With teh F1H1 treatment, average loblolly-pine height and volume exceeded that of the average slash pine. At age 4, the growth response due to increased nutrient supply was 13–29 times that of the best genetic response within F0H0 trees of the four slash-pine progenies. The best-growing slash-pine family (6–56) exceeded loblolly-pine growth under all four treatments and approximated the vigor shown by slash pine in the southern hemisphere.  相似文献   

20.
运用随机抽样法抽取马尾松成熟林分50个小班,调查胸径、树高、单位蓄积量及密度等测树因子,运用回归分析法进行测树因子相关性分析,结果表明,林分蓄积量对于密度、胸径、树高之间存在显著线性关系,其相关性数学模型可用三元线性回归方程y=b0+b1x1+b2x2+b3x3表示,其中,密度是影响林分蓄积量的主导因素。相关性变化趋势分析表明,在兼顾林分产量和林木径级的情况下,合理保留密度每667 m2为105株。  相似文献   

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