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栗瘿蜂是板栗生产上的重要害虫,属膜翅目瘿蜂科,又称栗瘤蜂.以幼虫在栗树芽内危害,被害芽逐渐膨大而形成虫瘿,树势衰弱,严重影响产量和质量,甚至引起树体死亡. 相似文献
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栗瘿蜂生物学特性及防治研究 总被引：2，自引：0，他引：2
1 生物学特性从 2 0 0 1年 3月起 ,在石棉县安顺乡新场村设固定样地对栗瘿蜂虫瘿的形成、发育进行了系统观察 ,并定期解剖虫瘿观察瘿蜂的发育情况 ,基本查清了栗瘿蜂为害期的生物学特性。栗瘿蜂以初龄幼虫在芽内越冬。越冬幼虫于 3月中旬板栗萌芽期开始活动取食。 3月下旬形成虫瘿并迅速膨大 ,至 4月中旬多数幼虫已成熟 ,虫瘿不再膨大 (见表 1)。2 0 0 1年 3月中旬初 ,从去年重灾区采集枯瘿 817枚 ,分装于广口瓶内 ,用纱布封口 ,每日记录羽化的天敌种类和数量。结果收集到在瘿内越冬的中华长尾小蜂ＴｏｙｍｕｓｓｉｎｅｎｓｉｓＫａｍｉｊ… 相似文献
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对锥栗栗瘿蜂在建瓯市的发生规律、冠层分布等进行了调查及无公害防治试验。结果表明:栗瘿蜂虫瘿以南向和下层分布居多;通过修剪、摘除虫瘿等无公害技术处理,对该虫防治可达到较好的防治效果。可在生产上大面积推广应用。 相似文献
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栗瘿蜂发生与防治的研究进展 总被引：2，自引：0，他引：2
栗瘿蜂（Dryocosmus kuriphilus Yasumatsu）属于膜翅目（Hymenoptera）瘿蜂科（Cynipidae）栗瘿蜂属,主要危害板栗（Castanea mollissima）,也危害茅栗（C．sequinii）和锥栗（C．henryi）,是影响栗树生长和结实的主要害虫之一。该虫先危害栗芽,同时分泌刺激性物质。在虫瘿形成过程中消耗树体大量营养,受害树树势衰弱, 相似文献
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栗瘿蜂发生期预测的研究 总被引：2，自引：0，他引：2
栗瘿蜂是严重影响板栗结实的主要害虫。由于具有生活隐蔽,发生期难以掌握的特点,是造成多年来各地栗瘿蜂人工防治成效低的主要原因之一。为此,我们自1988年起在系统了解栗瘿蜂生物学特性的基础上,对发生期的预报方法进行调查研究,并以此运用于防治,取得了良好效果。 材料和方法 地点在泰安市徂徕山林场和泰山林场,共选择不同环境条件、不同虫口密度的板栗纯林标准地7块,树龄25～35年生,生长良好。自萌芽后3日起,3天一次随机采取新瘿50个以上,室内剖查栗瘿蜂发育进度,直至成虫出孔止。测量出板栗芽长、雄花序长、雌花(栗棚)直径,计算雄花开放… 相似文献
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栗瘿蜂是板栗的主要害虫，在全国板栗产区普遍发生，危害严重。笔者十多年来从事栗瘿蜂的生物学特性、发生规律及综合防治的研究。于１９９８～１９９９年，笔者对栗瘿蜂的化学防治方法做了一些试验，取得了良好效果。１方法１．１供试农药５０％甲胺磷乳剂（湖北靳春农药厂）、４０％氧化乐果（湖北沙市农药厂）、８０％敌敌畏乳剂（武汉葛店化工有限公司）。１．２供试栗园孝昌县小悟乡乔湾板栗园，栗瘿蜂危害株率１００％。每株有瘿瘤２００～２０００个不等。１．３成虫期树冠喷药在粟瘿蜂成虫脱瘤期，于６月２５日、７月１０日共喷药２… 相似文献
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乐业县栗瘿蜂发生规律及防治方法 总被引：1，自引：0，他引：1
板栗瘿蜂属膜翅目瘿蜂科,又称栗瘿蜂,主要为害板栗,是板栗重要害虫之一,在我国各板栗产区均有危害。自上世纪90年代以来,随着乐业县山地综合开发面积逐年扩大,板栗栽培面积也逐年增多;但由于技术力量薄弱,加上栗农对栗瘿蜂缺乏科学的认知,以致该虫在乐业县板栗种植区危害面积逐渐扩大,危害程度也逐年加剧,根据对乐业县几个板栗种植主产区的调查统计显示 相似文献
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为了明确神农架地区野生板栗资源遗传背景,选用4对呈现多态性的叶绿体微卫星引物,对湖北省十堰辖区内野生板栗进行了遗传结构和叶绿体单倍型分析。结果表明4个位点在4个居群的53个样本中扩增出10个等位基因。等位基因数(A)平均为2.5,有效等位基因数(Ne)平均为1.696,PIC值平均为0.312,各遗传参数值远低于核基因组对群体研究的相应值。4个等位基因从53个样本中共给出5种单倍型,既有共享率超过66%的单倍型,在房县居群中也存在稀有单倍型,其中丹江口和房县板栗天然野生居群,具有较高的单倍型多样性,杂合度分别为0.4062和0.3794,明显高于其他地区,显示两地是板栗的分布及遗传多样性中心。基于cpSSR数据,对板栗地方品种与天然野生居群间的遗传结构、关系及地方品种的起源进行了初步探讨。AMOVA分析显示,83%的cpSSR变异存在于居群之间,17%来自居群内。研究表明,十堰地区野生板栗具有较高的多样性,叶绿体单倍型分析更能直观的表现野生板栗的区域分布规律。 相似文献
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Chestnut stands (orchards and coppices) are among the most typical elements of the southern European mountain landscape and
a protected habitat (9260 Castanea sativa woods) according to the European Union (Directive 92/43/EEC). As an anthropogenic landscape, they require specific measures
to address preservation or to guide their evolutionary trend. In the Northern Apennines, a landscape multiscalar-multitemporal
approach was adopted to highlight factors that have acted on the evolution of this habitat and which still might affect either
its preservation or its evolutionary dynamics. Using a diachronic GIS-approach, we analyzed old cadastral maps (drawn up 200 years
ago), and aerial photographs. Both the present distribution pattern of the woody species and the incidence of important chestnut
diseases were also surveyed. The factors explaining the current extent and species composition of the local chestnut forests
confirm their status as an anthropogenic habitat. The present landscape distribution of chestnut woods is heavily linked to
past human settlements. Chestnut blight and ink disease are more an indirect reason for past felling activities than an actual
direct cause of damage to trees, because of the hypovirulence spread and the limited incidence of the ink disease. Vegetation
dynamics of abandoned chestnut forests evolved only partly towards deciduous Beech and Hop Hornbeam stands, thus suggesting
both the possibility of a recovery of this cultivation and the need for new criteria for its management. 相似文献
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对板栗林下栽培不同的经济作物进行研究.结果表明:板栗园套种短梗五加具有投资少,收益高,见效快的特点,并且具有保持水土,改善板栗园生态环境的功效.最高每667 m2较单一栽培多收入1 165.75元,是辽东板粟产业继续发展壮大的较理想模式. 相似文献
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Nagashima Keiko Sands Roger Whyte A.G.D. Bilek E.M. Nakagoshi Nobukazu 《Landscape Ecology》2001,16(8):719-729
The expansion of plantation forestry in New Zealandduring the last century has altered the landscape and will continue to do so in the future. The implementation of recent resource management policy, the 1991 Resource Management Act (RMA), will also influence the impact of future plantation expansion on the landscape. It is necessary to analyze current land-use patterns in order to predict effects on future landscapes. This study analyzed the current land-use patterns of the Nelson region by examining the relationship between land-use and site conditions and by characterizing the distribution pattern of land-use depending on distance from the city. The distribution pattern was considered from an economic perspective, based on the Barlowe’s model of land use distribution. The relationship between the current land-use pattern and previous land management policy was also examined using the Land Use Capability. Consequently, in addition to the physical attributes of the land, the influence of land-use management policy was obvious. Thus the RMA will undoubtedly influence land-use changes in the future. It is therefore necessary to understand the factors determining changes in land-use patterns in conjunction with the district plan of the RMA to predict future changes in land-use.This revised version was published online in May 2005 with corrections to the Cover Date. 相似文献
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Throughout most of the north-west Iberian Peninsula, chestnut (Castanea sativa) woods are the principal deciduous woodland, reflecting historical and ongoing exploitation of indigenous forests. These
are traditionally managed woodlands with a patchy distribution. Eurasian nuthatches (Sitta europaea) inhabit mature deciduous woods, show high site fidelity, and are almost exclusively found in chestnut woods in the study
area. We studied the presence and abundance of nuthatch breeding pairs over two consecutive years, in relation to the size,
degree of isolation and intensity of management of 25 chestnut woods in NW Spain. Degree of isolation was assessed in view
of the presence of other woodland within a 1-km band surrounding the study wood. Wood size was the only variable that significantly
predicted the presence of breeding pairs (in at least one year, R
2 = 0.69; in both years, R
2 = 0.50). The number of pairs was strongly predicted by wood size, isolation and management (R
2 = 0.70 in 2004; R
2 = 0.84 in 2005); interestingly, more isolated woods had more breeding pairs. Breeding density was likewise significantly
or near-significantly (P ≤ 0.1) higher in small isolated woods, which is possibly attributable to lower juvenile dispersal in lightly forested areas
and/or to lower predator density in smaller and more isolated patches. Breeding density was higher (though not significantly
so) in more heavily managed woods, possibly due to the presence of larger chestnut crops and larger trees (with higher nuthatch
prey abundance). Our findings highlight the complexity of the relationships between the patch properties and the three studied
levels (presence, number and density of pairs), and also the importance of traditionally managed woodlands for the conservation
of forest birds. 相似文献
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山地板栗园覆草效应的研究 总被引：11，自引：1，他引：11
连续5年对山地板栗园进行稻草覆盖试验,厚度为10cm、15cm和20cm。结果表明:三种厚度都能不同程度地提高板栗产量,土壤有机质,N、P、K含量以及浅层土壤根系数量;5年间年均增产1260～2352kg/hm2,相对增产幅度为41%～76%,土壤有机质含量增加18.1%～45.7%,水解氮、速效磷、速效钾含量分别增加55.2～93.1、4.2～12.5、37.5～103.1mg/kg,0～30cm土层土壤10.0mm以下根系数量增加50～177条。经济学评估表明:以覆草15cm厚度为宜,5年年均增产2100kg/hm2,年增加纯收入8610元/hm2,产投比为5.56。 相似文献
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构建包含主要影响因子的最大密度线模型,为确定塞罕坝华北落叶松人工林适宜经营密度提供科学依据。本研究利用2019年塞罕坝森林资源清查数据,基于4种常用的最大密度线模型,构建包含主要影响因子的华北落叶松人工林最大密度线模型。结果表明：（1）4种基础模型的确定系数分别为0.388、0.348、0.348、0.419,其中模型M4的确定系数最大,拟合效果最优,最适用于塞罕坝华北落叶松人工林;（2）通过相关分析确定林龄、坡向是影响林分密度的主要因子,并在P<0.01水平上呈极显著相关;（3）构建了包含主要影响因子的华北落叶松人工林最大密度线模型,其中同时包含林龄和坡向的最大密度线模型拟合精度最高,其确定系数为0.720,拟合效果最优,该模型可为塞罕坝华北落叶松人工林多功能可持续经营提供科学依据。 相似文献