杉梢小卷蛾研究初报

杉梢小卷蛾属鳞翅目小卷蛾科。它以幼虫侵蛀杉木嫩梢,使杉梢枯死,严重影响立木的生长,是杉木主要害虫之一。 近几年来,此虫在金坛县普遍发生。1977年调查:方元茶场5年生杉木,主梢被害率在50—70％,雪布公社上阳大队新造杉木林主梢受害率在12％,主梢受害后,年平均高生长量为51.9—53厘米;而未受害的杉木,年平均高生长量为70.9厘米。因此,我所从1976年开始,连续4年,通过野外定期查虫观察、剥被害梢、室内饲养及点灯诱蛾等方法,对杉梢小卷蛾进行了研究,并进行了防治初步试验。 一、生活史 杉梢小卷蛾在我县,一年发生2—3代,以第1、2代幼虫危害最严重,少数分化为第3代。各代幼虫发生期:第1代     

应用菊酯油烟剂喷烟防治杉木种子园害虫试验

1993-1994年在洋口林场应用3Y－25型脉冲式烟雾机喷施0．05％溴氰菊酯油烟剂防治杉木种子园害虫的试验。结果表明：菊酯油烟剂喷烟可同时防治杉木球果麦蛾、杉木蝙长蝽及杉梢小卷蛾的成虫和幼虫。二次处理区球果虫害率比对照下降45．6％。     

双条杉天牛虫害木的早期识别与防治

双条杉天牛是杉木的主要害虫之一,对杉木林危害比较严重。双条杉天牛的卵孵化为幼虫后,一钻入树皮后就很难觉察,一但发现树干上出现羽化孔或树屑虫粪时,已经危害两年以上了,即使立即采取防治措施,也难于恢复树势。因此,尽早地识别被双条杉天牛危害的杉树,是挽救虫害木的关键,也是防治双条杉天牛的前提。一、双条杉天牛危害杉木早期症状通过我们一年多的观察,双条杉天牛的幼虫在6月中旬以前,大部分在杉木树皮内韧皮部蛀食,虫道小,对杉木生长影响     

江西首次发现雀丽毒蛾大面积危害杉木

报道雀丽毒蛾在江西首次大面积危害杉木林,对其成虫、卵、幼虫和蛹进行形态描述;阐述观察到的生活习性,根据该虫的危害特点,提出有效的防治方法。     

噻虫胺·高效氯氟氰菊酯微囊悬浮剂防治落叶松毛虫高龄幼虫的试验效果

落叶松毛虫(Dendrolimus superans)在春季大发生时多为3~6龄,可造成严重危害。通过使用噻虫胺·高效氯氟氰菊酯微囊悬浮剂对春季高龄幼虫进行防治试验,结果表明:使用该药剂稀释1000倍液防治3~6龄幼虫见效快、效果好;虫口密度不高时可采用1800倍液喷雾施药;防治3龄以下幼虫,可稀释2500倍液喷雾防治。     

杉木叶甲虫的防治

一、杉木叶甲虫形态特征和生活习性。杉木叶甲属鞘翅目叶甲科，成虫体小呈半椭圆形，体色为黑褐色，有强金属光泽，前翅角质坚硬为翅鞘，后翅为灰色透明膜质翅，触角丝状11节，呈水平状内微弯，复眼圆形，跗节5节。成虫具有趋光性和假死性，幼虫具有胸足3对。成虫产卵一般在春天或早夏，经7～15天孵化成幼虫，幼虫吃食幼枝后在土中化蛹，经数周后羽化成成虫。一年内可发生3～5代，到秋季入土蛰伏越冬。春来夏初正是杉木幼苗第一次生长高峰期，新梢幼嫩，杉木叶汁丰富，最易受到杉木叶甲虫的危害。     

建宁杉奕刺峨的研究

建宁杉奕刺蛾（ＰｈｌｏｓｓａｊｉａｎｎｉｎｇａｎａＹａｎｇｅｔＪｉａｎｇ）是我国南方杉木的重要食叶害虫，１年１代，幼虫７龄，以老熟幼虫在茧内，集中于树冠下浅土层中越冬。翌年５月上旬开始化蛹，羽化盛期在６月中旬。１－４龄幼虫食量甚微。山谷及低海拔纯林受害重，混交林受害轻。溴氰菊酯及一般有机磷药剂可有效防治３－４龄幼虫。结合春末抚育覆土可显著减少成虫羽化出土。应用辛硫磷等于老熟幼虫下树入土结茧之前，在地面喷药或以白僵菌防治，可大幅度压低虫口。     

杉梢小卷蛾幼虫空间分布型的研究

杉梢小卷蛾(Polychrosis cunninhamiacola)幼虫是杉木(Cunninghamia lanceolata)的主要食叶害虫之一,对杉木的危害极为严重.为确定杉木人工林中杉梢小卷蛾的空间分布类型,应用扩散系数等6种聚集度指标进行分析,通过杉木的受害状况与幼虫空间分布状况的对比验证,确定该虫在试验区域呈...     

杉木球果麦蛾种群动态规律的研究

杉木球果麦蛾Ｄｉｃｈｏｍｅｒｉｓｓｐ．是杉木的重要种实害虫，可造成杉木种子产量的严重下降。据４年调查结果，杉木球果麦蛾幼虫种群数量变动比较稳定，每样枝平均虫口密度０．２５－２．５头，无大起大落变化。由于幼虫在球果内危害，受气候、天敌等影响小，故存活率较高，平均存活率８５．８％。可以此作为参数，预报来年的种群消长趋势，为该虫的综合治理提供科学依据     

杉木叶枯病的调查

杉木叶枯病能严重影响杉木生长,甚至整株死亡。为了探讨防治途径,我们在同安县汀溪林场对杉木叶枯病的发病原因及发生规律进行了调查研究,现将调查和试验结果初报如下。     

Two consecutive yearly applications of orthene medicaps increase protection of grand fir against Western Spruce budworm

A random sample of Douglas-fir, Pseudotsuga menziesii var. glauca (Beissn.) Franco, and grand fir, Abies grandis (Dougl.), in Idaho in the United States, treated with Orthene Medicaps (acephate) in 1979 was treated again in 1980. One year after the second treatment in 1980, twice-treated (treated in 1979 and 1980) and once-treated (treated only in 1979) grand fir had significantly fewer western spruce budworm larvae per 100 buds than did control trees, and twice-treated grand fir had significantly fewer larvae than did once-treated. Defoliation of new shoots on twice-treated and once-treated grand fir was significantly less than that on control trees; defoliation did not differ significantly between twice-treated and once-treated trees for either species. Residues of acephate and methamidophos, its metabolite, monitored in midcrown foliage were detected 1 year after treatment.     

Ants and birds reduce western spruce budworm feeding injury to small Douglas-fir and western larch in Montana

Western spruce budworm, Choristoneura occidentalis Freeman, larvae on small Douglas-fir (Pseudotsuga menziesii var. glauca [Beissn.] Franco) and western larch (Larix occidentalis Nutt.) trees were protected from ant and bird predation during fourth instar to pupation. Significantly greater budworm densities were found on protected trees than on the controls at the end of the experiment, and significantly greater feeding injury was associated with increased budworm densities on fir. It is concluded that ants and birds remove budworm larvae feeding on small conifer trees and reduce injury up to 50%.     

福建省杉木种子园球果种子害虫调查及防治对策

１９９２—１９９３年对福建省７个良种基地进行杉木种子园种实害虫调查。结果表明，杉木球果麦蛾及杉木扁长蝽是危害杉木球果的主要害虫；平均变色、虫害果率分别为２７．７％、４６．７％。     

Nutrient cycling and distribution in different-aged plantations of Chinese fir in southern China

The distribution in tree biomass and understorey vegetation and annual biological and geochemical cycling of total nitrogen (N), phosphorus (P), potassium (K), calcium (Ca) and magnesium (Mg) were measured in young, middle-aged and mature plantations (8-, 14- and 24-years old) of Chinese fir (Cunninghamia lanceolata (Lamb.) Hook.) in southern China. Although >98% of nutrients occurred in the soil, soil nutrient content decreased with plantation age. Nutrient outputs from the soil exceeded inputs in stands of all ages but the net soil nutrient loss increased significantly for N, P and Ca with plantation age. Comparison of nutrient fluxes showed that the smallest (and hence limiting for nutrient cycling) fluxes were litter decomposition in the young plantation in contrast to canopy fluxes (apart from for Mg) in the middle-aged and mature plantations. Nutrient use efficiency, release of nutrients from litter decomposition and nutrient return, particularly in litterfall, increased significantly with plantation age. These results suggest that, as stand age increases, nutrient cycling in Chinese fir plantations is increasingly dominated by biological processes and becomes less dependent on external nutrient sources in rainfall and the soil. It therefore appears that prolonging the rotation length of Chinese fir plantations by approximately 5 years could be beneficial for maintaining the soil nutrient status for successive plantings.     

杉木-山苍子-作物复合经营模式土壤肥力的研究

通过对杉木-山苍子(A)、杉木-山苍子-黄豆(B)、杉木-山苍子-烟叶(C)及对照的纯杉林土壤生物学活性、土壤化学性质、土壤结构、孔隙组成和水分性状等研究,结果表明:模式B、C表层土壤结构性状变差,土壤营养元素含量下降,土壤生物学活性减弱,但底层土壤熟化程度提高。为了维持幼林地土壤肥力,模式B、C应适当降低耕作强度,缩短间种年限,同时适当增加N和P肥使用量。模式A具有良好的改良土壤能力,是南方林区优良的杉木混农模式。     

不同林龄杉木人工林土壤微生物群落代谢功能差异

【目的】研究不同林龄杉木人工林土壤理化性质以及微生物对碳源利用的差异,明确林龄对土壤微生物功能多样性的影响,为杉木人工林可持续经营管理提供理论依据。【方法】在福建武夷山脉选择3、12和38年生的杉木人工林,采用Biolog-ECO法研究不同林龄杉木人工林表土层(0~20cm)土壤微生物对碳源的利用特征,并对土壤微生物利用各类碳源的特性进行热图分析、主成分分析(PCA)和相关性分析,揭示利用碳源的差异及导致差异的主要影响因素。【结果】不同林龄杉木人工林土壤微生物群落的代谢活性、Shannon-Wiener多样性指数、Pielou均匀度指数、Simpson优势度指数、McIntosh多样性指数和McIntosh均匀度指数均随林龄的增加而增加。在96~168h培养时间内,38年生杉木人工林土壤微生物群落的代谢活性显著高于12年生和3年生(P<0.05)。38年生对酚酸类、胺类和氨基酸的利用强度较大,12年生对酚酸类、多聚物和氨基酸的利用强度较大,3年生对多聚物、羧酸和碳水化合物的利用强度较大,并且38年生土壤微生物群落代谢碳水化合物、氨基酸、羧酸和胺类的强度显著高于3年生,而12年生和3年生土壤微生物群落对6类碳源的利用率差异不显著(P>0.05)。热图分析结果表明:38年生和12年生杉木人工林土壤微生物群落能够代谢31种碳源底物,而3年生杉木人工林土壤微生物群落仅能代谢19种碳源底物。环境因子中,土壤pH、全氮、速效钾和碳氮比能够显著影响微生物群落的代谢功能。【结论】38年生杉木人工林表土层(0~20cm)土壤微生物群落代谢活性和多样性最高,3年生最低,pH、全氮含量随林龄的增加而上升,碳氮比则随林龄增加而下降,因此林龄是驱动杉木人工林土壤生物学和非生物性质变化的重要因素。     

湖北省森林生物防火现状及发展趋势

森林火灾是危害森林资源的重要自然灾害,突发性强、危害性广、毁灭性大,历来受到社会的广泛关注和重视。森林生物防火通过防火林带建设、林下枯落物降解等措施主动降低森林火灾隐患、减小了森林火灾损失。今后应加强防火专家系统建设、防火林带布局拓扑优化以及森林生物防火技术标准等方向研究,达到森林生物防火标准化、自动化和信息化,发挥森林生物防火的最佳效果。     

A push–pull strategy to control aphids combines intercropping with semiochemical releases

Even if insect pest populations can be reduced by increasing plant diversity through intercropping, natural enemies are not always favored in such systems. Alternatively, semiochemical substances have been tested to enhance biological control, with inconsistent results. Combining both strategies can be an interesting way to maximize pest control. In this work, a 2-year setup involving wheat–pea strip intercropping combined with the release of E-β-farnesene (EBF) or methyl salicylate (MeSA) was tested as a push–pull strategy to simultaneously repel aphids and attract beneficials. Two types of slow-release formulation (i.e., oil and alginate beads) containing EBF or MeSA were deployed with the intercropping. The abundance of aphids was significantly decreased, while hoverfly larvae and mummified aphids increased on both pea plants and wheat tillers by the release of oil-formulated EBF and MeSA. The proportion parasitism of the aphid-parasitism rate [mummies/(aphids + mummies)] was also increased by treating both crops in both years. Releasing EBF through oil rather than alginate beads proved significantly better for attracting natural enemies and reducing aphids. Aphids were negatively correlated with the density of hoverflies (both adults and larvae) and numbers of mummies. All these results showed that combining intercropping with the release of EBF or MeSA formulated in oil can significantly reduce aphid density and attract their natural enemies. Therefore, the combination of both strategies could help farmers reduce the use of insecticides.     

杉木萌芽更新原理及技术述评

本文对杉木休眠芽的生物学、生态学特性和萌发机制，萌芽林的生长发育规律和培育技术等进行了总结，并对萌芽更新的优缺点和适用性进行了评价。