茶蛀梗虫的发生与防治

茶蛀梗虫又称油茶蛀茎虫(Casmara patrona Meyr)。属鳞翅目织蛾科。是我省油茶和茶树的主要害虫之一。据在我区兴国、全南、定南、安远等县调查,油茶被害株率一般为30—40%。被害后在蛀道以上的枝干不久即枯死,尤其是幼树被害后,常全株死亡,严重威     

柳州市油茶枝干病虫害调查初报

经对广西壮族自治区柳州市两县四乡九个村油茶林进行抽样调查,发现油茶枝干病虫害种类有相思拟木蠹蛾、油茶织蛾、黑跗眼天牛、茶褐天牛、螽蟖、油茶半边疯、油茶肿瘤病、樟寄生、桑寄生等9种,主要病虫害相思拟木蠹蛾、黑跗眼天牛的危害程度中等至严重,油茶织蛾为轻微至中等,茶褐天牛为中等;油茶半边疯、油茶肿瘤病轻微至严重.说明油茶枝干...     

油茶林下养鸡对油茶虫害防控和杂草密度的影响

对油茶Camellia oleifera林下养鸡Gallus gallus domesticus对蛴螬Popillia spp.(主要为铜绿丽金龟Anomala corpulenta的幼虫形态),油茶织蛾Casmara patrona和茶籽象甲Curculio chinensis 3种主要害虫危害率和杂草密度的影响进行了研究。结果表明,油茶林下养鸡能显著降低蛴螬、茶籽象甲和油茶织蛾对油茶的危害,与对照样地间存在显著差异(P0.05);同时,试验样地内杂草也得到有效控制。因此,适度开展林下养鸡可明显提升对油茶林害虫和杂草的防控。     

寄主树木、寄主和环境因子对松褐天牛深沟茧蜂寄生率的影响研究

[目的]松材线虫病是我国对森林危害和威胁最严重的病害,控制其传播媒介昆虫松褐天牛是防治松材线虫病的主要手段。作者发现的松褐天牛深沟茧蜂(Iphiaulax monochamusi Yang)是寄生松褐天牛中老龄幼虫的重要天敌。为明确松褐天牛深沟茧蜂的寄生率与寄主树木、寄主和环境因子的关系,开展了本研究。[方法]通过解剖46株松褐天牛危害致死的马尾松,调查了松褐天牛深沟茧蜂寄生率与马尾松、松褐天牛和环境因子之间的关系。[结果]调查研究表明:寄主树木的高度、胸径和树龄对松褐天牛深沟茧蜂寄生率没有显著影响,松褐天牛的数量对松褐天牛深沟茧蜂寄生率亦没有显著影响,而松褐天牛幼虫龄期和松褐天牛幼虫在树干上的位置显著影响松褐天牛深沟茧蜂寄生率。松褐天牛深沟茧蜂寄生率与松褐天牛龄期呈显著正相关,其偏好寄生3~5龄幼虫;就天牛在其危害寄主树木上的位置而言,松褐天牛深沟茧蜂偏好寄生马尾松主干上部和在韧皮部危害的松褐天牛幼虫,其对位于马尾松树干上部的寄主幼虫寄生率最高,达27.38%,对在韧皮部生活、危害的寄主幼虫寄生率为20.18%,显著高于位于木质部生活的寄主幼虫寄生率(5.46%)。逐步回归分析表明:影响松褐天牛深沟茧蜂寄生率的关键环境因子是寄主树木的坡位和其它天敌寄生率,其中,坡位与松褐天牛深沟茧蜂呈显著正相关,其它天敌寄生率与松褐天牛深沟茧蜂寄生率呈显著负相关。[结论]以上研究初步明确了松褐天牛深沟茧蜂的寄生率与寄主树木、寄主害虫和天敌之间的关系,为今后利用该重要天敌控制松褐天牛打下了基础。     

油茶象危害油茶果实的初步研究

对福建省闽侯桐口国有林场油茶杂交试验林果实的果径、果高、果重、籽重(种仁重)以及果实受害率等进行测定,分析油茶象对油茶果的危害情况。结果表明:在调查的油茶林分中,株受害率为94.7%,平均虫果率为14.7%;健康果平均果径为3.01 cm,显著地大于虫果的2.86 cm;健康果平均果高为3.05 cm,显著地高于虫果的2.84 cm;健康果平均果重为16.8 g.个-1,极显著地大于虫果的果重;健康果籽重为6.2 g.个-1,极显著地大于虫果籽重4.8 g.个-1;结果表明:油茶象的危害严重影响了油茶果的生长和油茶的产量。     

莱粉蝶绒茧蜂生活习性的初步观察

菜粉蝶绒茧蜂(Apanteles glon mer-atus)是树粉蝶和天幕毛虫幼虫的主要寄生蜂之一,发生于6月上、中旬,寄生于树粉蝶的寄生率最高达59.1%,平均26.3%。1 菜粉蝶绒茧蜂越冬态及发生规律菜粉蝶绒茧蜂以老龄幼虫或蛹在树粉蝶幼虫体内越冬,翌春寄主虫开始取食后,蜂老龄幼虫开始钻出寄主体外,结茧化蛹。该蜂发生规律:6月份在树粉蝶幼虫体旁结茧化蛹,7月份在白菜地菜青虫体下结茧化蛹,8月份在甘兰地菜青虫上结茧化蛹羽化,     

不同生境油茶林油茶史氏叶蜂的发生与危害程度比较

通过比较不同生境油茶林区油茶史氏叶蜂幼虫危害程度、同一种生境距林边不同距离油茶史氏叶蜂的危害程度,分析了油茶史氏叶蜂对油茶春梢发育、夏梢发育、花芽分化率、花芽数目、落果率等的影响。结果表明:油茶史氏叶蜂对油茶的春梢发育、夏梢发育、花芽分化率、春梢上花芽数目、同期的落果率等有显著危害,且危害程度和林区的生态多样性相关;不同生境下,生态多样性越低,危害越严重;同一生境下,距混合林区距离越远,危害程度越重,说明保护油茶林区及周边生境的生态多样性,对防治和控制油茶史氏叶蜂是必要的。另外通过间接证据,提出了白头鹎Pycnonotus sinensis和伯劳Lanius schach等食虫鸟类是油茶史氏叶蜂幼虫重要捕食性天敌的初步结论。     

小窄径茧蜂林间套笼接蜂试验

小窄径茧蜂林间套笼接蜂试验结果表明,影响小窄径茧蜂寿命和林间寄生活动的主要因素是接蜂时间和套笼内温度。７ 月下旬接蜂,寄生率为８．５２％ ～８．９０％ ,７ 月上旬接蜂,寄生率只有１．４０％ ～２．１６％ 。笼内温度超过３０～３４℃,小窄径茧蜂存活时间只有２～４天,少数可存活６～７ 天。在抚顺地区７ 月下旬至８月初是小窄径茧蜂寄生活动的最佳时间。试验表明,小窄径茧蜂可以在我国兴安落叶松鞘蛾上寄生并安全越冬。     

油茶的一种新害虫——黑足角胸叶甲

报道了危害油茶的新害虫--黑足角胸叶甲Basilepta melanopus.现有文献仅记载该虫严重危害茶树,也可取食珍珠菜,但未见危害油茶的报道.对福建省清流县、邵武市油茶林样地的调查表明:油茶株受害率100%,叶片受害率15%～90%,危害较为严重.介绍了黑足角胸叶甲成虫形态特征、分布范围、危害特征以及生物学特性等,并提出了防治建议.     

利用管氏肿腿蜂防治松幽天牛幼虫试验

松幽天牛Asemum amurense Kraatz是典型的次期性蛀干蛀根害虫,也是松材线虫的传播媒介昆虫之一,严重威胁着林间长势衰弱的马尾松Pinus massoniana。本研究调查松幽天牛的危害情况,按照1∶1,1∶2,1∶3,1∶4的虫蜂比于室内外分别接种管氏肿腿蜂Sclerodermus guani Xiao et Wu防治松幽天牛低龄幼虫,并筛选接种最适虫蜂比例。结果表明:松幽天牛主要危害衰弱木、松褐天牛Monochamus alternatus危害木和枯死木,平均虫口数量分别为27,27,70头/株,最多为152头/株,有虫株率为11.99%。室内试验中按虫蜂比为1∶3接种时,寄生成功率最高为60.00%。林间试验中按虫蜂比1∶4接种时,防治效果最好,校正虫口减退率为56.47%。     

川南地区丛生竹硬头黄竹带状皆伐对其生长及产量的影响

以长宁县硬头黄竹为研究对象,分别在龙头镇、竹海镇样地设置长度均为60 m,宽度为3 m、6 m、9 m皆伐带;3 m^6 m、6 m^9 m皆伐带间设置保留带,保留带宽度均为6 m;另外在样地附近设置一个6 m×60 m对照带。采用机械式带状皆伐1年后,通过调查和数据处理,分析其生长状况,显著性特征、生物量(地上部分)。结果表明:(1)两个样地中均发萌枝,且萌枝面积均为9 m皆伐带>6 m皆伐带>3 m皆伐带。从龙头镇来看,各皆伐带和保留带的发笋量均明显高于对照带,最大为6 m^9 m保留带,达到4 976±97株·hm-2;从竹海镇来看,3 m皆伐带、3 m^6 m保留带、6 m^9 m保留带发笋数高于对照带,6 m^9 m保留带发笋数最高,达到11583株·hm-2。(2)单因素方差分析(ANOVA)和多重比较表明,龙头镇和竹海镇竹笋平均胸径除6 m皆伐带和9 m皆伐带间差异不显著外(p>0.05),其他每个带之间差异均显著(p<0.05);龙头镇竹笋平均高除3m皆伐带和6m皆伐带之间、6 m皆伐带和9m皆伐带之间差异不显著外(p>0.05),其余各带之间差异均显著(p>0.05),竹海镇竹笋平均高除6 m皆伐带和9 m皆伐带之间差异不显著外(p>0.05),其余各带之间差异均显著(p<0.05)。(3)根据张鹏等在长宁县对硬头黄竹胸径与生物量拟合的指数回归模型,可以计算出经过带状皆伐改造试验后,龙头镇3 m^6 m保留带、 6 m^9 m保留带1 a生竹每公顷产量分别比对照提高了92.76%、175.21%。竹海镇3 m^6 m保留带、 6 m^9 m保留带1a生竹每公顷产量分别比对照提高了111.89%、161.58%。(4)通过本试验对该地硬头黄竹进行带状皆伐改造,发现6 m^9 m保留带竹林长势最好,生物量最高,改造效果最好。     

淡紫拟青霉不同菌株对南方根结线虫卵寄生率三种处理方法的比较

利用来自不同地域的淡紫拟青霉的13个菌株，分别用其孢子液处理南方根结线虫分散卵粒、菌丝处理分散卵粒、孢子液处理卵囊以评价淡紫拟青霉对南方根结线虫的寄生性。在被试所有菌株中，同一菌株三种不同方法对根结线虫卵的寄生率相比，孢子液处理卵囊均明显高于其他两种处理。不同菌株对南方根结线虫卵的寄生率有很大的差异。三种处理方法结果显示618号菌株寄生率均为最高。菌株对卵的寄生率与菌株地理来源无明显相关性。     

永安市油茶栽培现状与发展对策

通过样地调查、数据收集和统计分析结果表明,永安市现有油茶林面积约988.77 hm2,槐南乡和安砂镇是油茶主要分布区,品种以普通油茶为主,管理粗放,果实产量低,出油率低,经济效益不高。对现阶段永安市油茶存在的问题及对未来油茶发展的趋势做出综合评价,提出一些适于永安市油茶发展的具体对策。     

不同造林技术措施对黎蒴幼林生长的影响

文章对韶关市翁源县林科所附近于2005年3月营造的12种不同造林技术措施黎蒴试验林进行研究,比较其中不同施肥措施、不同造林密度和不同整地规格下林木生长状况的差异,找出有利于黎蒴幼林生长的关键造林技术措施。研究结果表明：（1）12种不同造林技术措施下的树高、地径、冠幅等生长指标存在显著差异;（2）12号标准地树高生长显著高于其它标准地,8号标准地地径和冠幅生长最旺盛;（3）在不同施肥量的试验中,12号标准地黎蒴的生长最好;（4）在不同造林密度的试验中,8号标准地黎蒴的生长最好;（5）在不同整地规格的试验中,6号标准地黎蒴的生长最好;（6）聚类分析结果,将12个标准地林木的生长速度分为快、中和慢3种类型。     

Effect of Gap Size on Seedling Establishment of Tsuga longibracteata

Effects of three gaps which are large （118 m^2）, medium （86 m^2） and small （20 m^2）, respectively, and under canopy of Tsuga longibracteata forest on the seedling establishment of T. longibracteata were studied through seed burial experiments from December 2003 to January 2005 in Tianbaoyan National Nature Reserve of Fujian, China. The results showed that the area of gap had an evident effect on the seedling establishment of T. longibracteata. The seedling emergence rates of T. longibracteata in plots of large gap, medium gap, small gap and under canopy were 10%, 10%, 4% and 6%, representing an increasing trend along with the gap size increasing without a significant difference. Rain eroding and insects feeding were two main factors leading to seedling death. The larger the gap size was, the more seedlings were killed by rain erosion and the fewer seedlings were killed by insects feeding. The emergence time of seedlings was almost same in all plots while their death time was different respectively. The gap size had a significant impact on seedling survival rate. The seedling survival rate was highest in the medium gap plot （27.0%） and next to the highest in large gap plot （7.3%）, and seedling in small gap plot and under canopy plot died out after one growing season. Increased light supply in gaps was favorable for the seedlings growth and survival. Increased light supply in the large gap could enhance the growth of seedling leaf and root of T. longibracteata, and the seedling in turn allocated more dry mass to root and leaf, but it has little impact on the growth of stem. This research indicates that T. longibracteata is a pioneer species and its seedling establishment need a medium or large gap （〉50 m^2）.     

不同地理种源白木通经济性状差异的比较

为了选育食用、油用及药用价值较高的白木通品种,对8个不同地理种源白木通的果实经济性状、果肉营养成分、藤条药用成分、种子含油率及脂肪酸组成相关指标进行了方差分析和多重比较。结果表明:(1)种源间的果实性状中各指标均存在显著性差异。安徽省宁国县军天湖乡天湖街道种源的可食率较高,超过30%,单果质量和果肉质量均最大,分别为276.64 g和84.82 g,显著高于其它7个地理种源,具有较高的食用价值。(2)种源间种子含油率及脂肪酸组成除不饱和脂肪酸外均存在显著性差异。安徽省宁国县军天湖乡天湖街道种源的含油率最高,为47.09%,不饱和脂肪酸的含量也较高,为72.61%,具有较高的油用价值。(3)种源间果肉营养成分性状存在显著性差异。江西省九江市东林寺东林村种源的总糖和还原糖含量最高,分别为32.35%和16.31%,显著高于其它7个地理种源,总酸及维生素C含量中等,果肉营养价值较高。(4)种源间藤条药用成分存在显著性差异。重庆市武隆县仙女乡白果村种源的齐墩果酸B含量最高,达到0.6%,显著高于其它7个地理种源,且其藤条的总药用成分含量最高,具有较高的药用价值。     

杉木人工林材种结构的立地及密度效应研究

采用30年生未间伐的杉木人工林连续观测数据,研究了不同林龄立地质量、林分密度对林分材种结构的影响。结果表明:初植密度相同时,立地质量越好各材种出现时间及达到最大出材率的时间越早,22立地指数初植密度1 667株·hm^-2的小径材最大出材率出现时间较16立地指数初植密度1 667株·hm^-2早4 a,中径材最大出材率出现的时间早6 a;立地指数相同时,随初植密度增加小径材出材率的峰度及峰值均减小,20立地指数样地中,初植密度为1 667株·hm^-2的小径材出材率峰值较初植密度为10 000株·hm^-2的高17%,而初植密度对中径材、大径材影响不大;在林分发展的不同时期,林分密度对材种出材率的影响不同,30年生时林分蓄积相近的但初植密度不同的样地,初植密度越大小径材出材率越高,大径材出材率越低。     

Modelling probability of snow and wind damage in Scots pine stands using tree characteristics

Predictions of damage risk from snow and wind at sites using tree characteristics of Scots pine (Pinus sylvestris L.), were made using a subset of data from permanent sample plots within the Swedish National Forest Inventory (NFI). The plots were sampled twice at five-year intervals between 1983 and 1992. A logistic risk assessment model was developed using data originating from 286 plots, dominated by Scots pine (> 65% of basal area), within one county situated in the boreal zone in northern Sweden (Västerbotten). The model was evaluated with NFI-data from two other counties, one adjacent to Västerbotten (Västermorrland, 99 plots), which is also in the boreal zone, and one (Kalmar, 138 plots) in the hemi-boreal zone in southern Sweden. In each plot, measurements at first inventory of tree characteristics for the largest undamaged sample tree, and measurements at second inventory of damage from snow and wind on all sample trees were used to develop a logistic model that predicts the damage probability for each site. The best predictors were upper diameter (ud, diameter at 3 or 5 m) and the ratio of height/diameter at breast height (rhd). According to the model calculations, the overall damage probability never exceeded 0.26 for any of the sample plots used for model development. At a given ud the probability of damage is higher for a site with trees of low rhd. The fit of the model was better for the adjacent Västernorrland county than for the southern county, Kalmar. This inferior predictability was explained by differences in tree characteristics between Kalmar and the other counties. The results show that it is possible to predict damage from snow and wind at a site by using only single tree characteristics.     

Soil microbial biomass, abundance, and diversity in a Japanese red pine forest: first year after fire

This study was conducted to determine the microbial biomass carbon and abundance and diversity of soil microorganisms immediately after the occurrence of fire in a Japanese red pine forest, and to determine the pattern of microbial recovery within the first year after fire. The effects of fire at three slope positions were also determined. Three plots in each of the burnt and unburnt areas, measuring 10 × 10 m, were established. The first plot was located at the valley bottom, the second plot was located at the middle slope, and the third plot was located at the ridge. Analysis showed that for all parameters studied, the three plots in the unburnt area did not differ significantly and so they were treated as one control plot. The microbial biomass, abundance, and diversity structure in the unburnt and burnt plots showed significant differences. The unburnt area had the highest biomass carbon, abundance, and diversity, followed by the valley bottom, the middle slope, and then the ridge in the burnt area, and significant differences in the burnt plots were found between the valley bottom, the middle slope, and the ridge. The microbial diversity in the burnt area differed from that of the unburnt area, the microbial diversity being significantly lower in the burnt area, and the ridge was shown to have been the most affected by fire.     

Parasitic plant in natural Boswellia papyrifera stands at Humera,Northern Ethiopia

In Boswellia papyrifera （Del.） Hochst natural stands, we stud- ied the association of parasitic plants with B. papyrifera trees from which frankincense was tapped and marketed for domestic and export markets. Data on the rate of infection of parasitic plants on B. papyrifera was collected in three transects located at separate locations around Baha kar, northern Ethiopia. Each transect had ten circular sample plots of 400 m2 and separated by 100 m. Species composition, DBH, height, crown di- ameter, number of main, secondary and tertiary branches and number of parasitic plants on individual trees were recorded. Sixteen tree species were recorded in the combined sample plots. The parasitic plant associ- ated with B. papyrifera was identified as Tapinanthus globiferus. This parasite infected 38% of Boswellia trees in sample plots. The infection rate of the parasitic plant varied from 1 to 33 per Boswellia tree. The infection of T. globiferus on B. papyrifera was predominantly limited to tertiary small branchlets arising from secondary branches; parasitic plants were absent on thick main and secondary branches. In all plots, infectionof T. globiferus was exclusively limited to Boswellia trees. The influence of T. globiferus parasitism on growth of Boswellia trees and its influence on yield of incense production needs further investigation. Management of natural stands for frankincense production should include measures to reduce infection by T. globiferus.