首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 203 毫秒
1.
滇东南橡胶树寒害后次期性害虫危害状况调查   总被引:1,自引:0,他引:1  
调查了2011年1月云南滇东南橡胶树遭受特大寒害后,引发了以橡胶树小蠹虫类为主的次期性害虫的严重发生和危害,共调查橡胶树6541株,其中受小蠹虫危害株418株,橡胶树虫蛀率6%,共采集成虫标本232头,种类分属小蠹科Scolytidae、长小蠹科Platypodidae、锯谷盗科Siovanidae、露甲科Nitidulidae等4科4属5种,暗翅材小蠹(Xyleborus semiopacus)和对粒材小蠹(Xyleborus perforans)为优势种;调查还对由于频繁的自然灾害和长年的营养失衡导致橡胶树群体衰退是橡胶林次期性害虫大发生的潜在和根本的原因进行探讨;提出需要对滇东南植胶环境重新研究和评价,对植胶半个多世纪所依循的技术体系和经营体制进行重新审视,以期实现重大变革,使滇东南植胶业得以持续发展。  相似文献   

2.
长小蠹聚集信息素研究概况   总被引:1,自引:0,他引:1  
长小蠹属(Platypus)昆虫是危害森林生态系统的重要类群,严重时可造成林木大面积枯死。聚集信息素可用来监测长小蠹的种群密度,进行大规模诱捕和中断交配行为。本文从长小蠹属昆虫的聚集行为,聚集信息素的产生和释放,聚集信息素的化学组成以及应用等方面综述了长小蠹聚集信息素的研究概况。  相似文献   

3.
陈青  梁晓  伍春玲  陈谦  张哲 《热带作物学报》2019,40(12):2432-2439
本研究旨在明确12种聚集信息素对橡胶小蠹虫的诱捕效果。采用常规田间害虫调查结合统计学分析的方法,比较12种聚集信息素对橡胶小蠹虫的诱捕效果。结果表明,12种聚集信息素对橡胶小蠹虫的诱捕效果在田间诱捕器不同间距、不同悬挂高度存在显著差异,间距20、35和50 m的诱捕效果均显著高于间距65和80 m,悬挂高度2.0、2.5 m的诱捕效果均显著高于1.5、3.0和3.5 m,其中(S)-(-)-小蠹烯醇、(S)-(+)-小蠹二烯醇、(4S)-顺式-马鞭草烯醇诱捕效果最好,间距20、35和50 m的平均单日诱捕虫数分别为56.89、59.06和56.42头,54.69、57.38和53.89头,51.27、54.81和50.36头,悬挂高度2.0和2.5 m的平均单日诱捕虫数分别为57.89和59.06头、53.77和57.38头、50.63和54.81头;对粒材小蠹(Xyleborus perforans)和循胸材小蠹(Xyleborus aquilus)的诱捕数量分别为诱捕害虫总数的48.28%和41.12%、47.89%和41.08%、47.69%和41.05%,平均单日诱捕虫数分别为28.51和23.69头,27.48和23.00头,26.14和21.95头。α-蒎烯和二甲基小蠹诱对橡胶小蠹虫也具有较好的诱捕效果,间距20、35和50 m的平均单日诱捕虫数分别为19.24、22.16、18.12头和18.42、20.96、18.12头;悬挂高度2.0和2.5 m的平均单日诱捕虫数分别为18.23和22.16头、16.32和20.96头;对粒材小蠹和循胸材小蠹的诱捕数量分别为诱捕害虫总数的47.26%和40.02%、47.12%和40.02%,平均单日诱捕虫数分别为10.47和8.87头,9.88和8.39头。随着放置时间的增加,12种信息素对橡胶小蠹虫的诱捕效果呈现先逐渐增加,至30 d时达到高峰,而后又逐渐下降,至60 d后显著下降。(S)-(-)-小蠹烯醇、(S)-(+)-小蠹二烯醇、(4S)-顺式-马鞭草烯醇对橡胶小蠹虫诱捕效果最好,α-蒎烯、二甲基小蠹诱对橡胶小蠹虫也具有良好的诱捕效果,上述5种聚集信息素诱捕橡胶小蠹虫的适宜田间间距为35~50 m,适宜悬挂高度为2.0~2.5 m,有效期为60 d。  相似文献   

4.
咖啡果小蠹[Hypothenemus hampei (Ferrari)]是2019年新入侵海南的一种严重威胁全世界咖啡生产的害虫,对海南甚至全国咖啡产业的健康发展构成重大威胁。为尽快了解咖啡果小蠹的习性,以及为今后该害虫的防控技术提供基础数据,本研究观察了咖啡果小蠹的假死行为和耐饥能力,并探讨短时高温对其致死效应。结果表明:24h不饲喂任何食料对咖啡果小蠹成虫的假死行为无显著影响;45℃短时高温处理2 h显著提高了咖啡果小蠹成虫出现假死反应的比例和时长,假死反应出现比例达72.0%,假死时长为320.33 s,显著高于26℃下的假死时长(43.26 s)。咖啡果小蠹成虫具有较强的耐饥能力,在不提供任何食料的情况下,其最长存活时间可达204 h,平均存活时长达90.17 h。咖啡果小蠹成虫经短时高温处理后,处理温度与处理时长均显著影响其存活率,随着处理温度的升高及处理时间的延长,死亡率逐渐增加。45℃处理6 h后校正死亡率达94.92%;处理12 h的死亡率达100%;36℃和39℃处理6 h及以下时长对咖啡果小蠹的存活能力影响较小,36℃和39℃处理6 h,处理后24 h的校正死亡率分...  相似文献   

5.
基于MaxEnt模型的对粒材小蠹的适生性分析   总被引:1,自引:0,他引:1  
对粒材小蠹(Xyleborus perforans Wollaston)是天然橡胶产区重要的危险性害虫之一,是世界重要的检疫性有害生物。利用MaxEnt和GIS软件预测该虫在中国范围内气候条件适宜存活的区域,在此基础上结合寄主分布特征,定量地获得了对粒材小蠹的潜在发生区。预测结果显示:对粒材小蠹的适生区主要分布在东亚、东南亚、加勒比海沿岸、非洲西部和东部、大洋洲北部、美国南部和墨西哥部分地区;在中国,该小蠹能广泛分布在华南地区和西南的部分地区,并提供了ArcGIS 适生区预测分布图;最湿润月降水量、年温度变化、最热季度降水量和昼夜温差月均值是影响对粒材小蠹空间分布的4个主要环境因子,计算结果经ROC 曲线分析法验证,MaEnt生态位模型的AUC值为0.936。表明预测获得了较好的效果,此研究可为对粒材小蠹的检疫及防治决策的制定提供科学依据。  相似文献   

6.
云南橡胶树小蠹虫研究   总被引:2,自引:0,他引:2  
云南植胶区橡胶树小蠹虫为4个科17个种的小蠹虫群体,是主要蛀食橡胶树死亡组织的次期性害虫,长期生存在橡胶林中。1990年后,橡胶树小蠹虫为害逐渐明显,表现大量发生,虫害树快速死亡,造成严重的经济损失。经2000-2007年的研究表明:橡胶树小蠹虫种群结构已发生重要变化,活蛀性的角面长小蠹(Platypus secrelus Sampson)、小杯长小蠹(P.calicutus Chapuis)已发展成为优势种,致使橡胶树小蠹虫种群从次要害虫逐渐变为主要害虫,成为橡胶树衰退重要的促进因素(Contributing factors);橡胶树衰退,特别是过度的乙烯利刺激割胶导致的橡胶树衰退,是促变小蠹虫群体结构并逐渐发展成为主要害虫的主要诱因。因此,提高管理水平,调控生产技术,使胶林生态系统达到新的平衡,才是有效地控制橡胶树衰退趋势和控制小蠹虫为害于经济阈值之下的正确途径。  相似文献   

7.
橡胶小蠹虫的危害和防治   总被引:4,自引:0,他引:4  
描述为害橡胶树的小蠹虫如角面长小蠹,小杯长小蠹、锥尾长小蠹、对粒材小蠹、橡胶肩角粉蠹、短鞘长腹筒蠹等的形态特征、生物学特性,提出防治方法。  相似文献   

8.
在毛竹林5个区组内分别采取劈杂(X2)、劈杂+施肥(X3)、劈杂+深翻+施肥(X4)和对照(X1)4种处理措施,翌年测定各处理小区春笋产量并进行经济效益分析。结果表明,竹笋产量在各处理间有极显著差异,在各区组间差异不显著。4种处理措施中,X4、X3与X1、X2之间竹笋产量差异极显著,X4与X3之间差异显著、X1与X2之间差异不显著,表明劈杂对竹笋产量影响有限,施肥和深翻均能显著促进竹笋增产。经济收益以X4为最大,每公顷可增加收益3475.5元,明显高于X3和X2,说明抚育施肥可以取得显著的经济效益。  相似文献   

9.
为了研发基于(S)-(-)-小蠹烯醇诱捕橡胶小蠹虫的安全高效诱捕技术,系统开展了不同(S)-(-)-小蠹烯醇诱芯对橡胶小蠹虫的诱捕效果试验。结果表明,自制的(S)-(-)-小蠹烯醇海绵诱芯和无纺布型诱芯对橡胶小蠹虫的诱捕效果最好,整个试验周期内平均单日单个诱芯诱捕器诱捕虫数分别为69.16头和66.22头,田间诱捕效果先逐渐增加,30 d时达到高峰,而后又逐渐下降,60 d后显著下降,1~60 d的平均单日单个诱芯诱捕器诱捕虫数分别为75.22~120.45头和70.69~112.22头。储藏瓶型诱芯对橡胶小蠹虫也具有良好的诱捕效果,平均单日单个诱芯诱捕器诱捕虫数为24.85头,田间诱捕效果先逐渐增加,至10 d时达到高峰,而后又逐渐下降,至30 d后显著下降,1~30 d的平均单日单个诱芯诱捕器诱捕虫数为48.53~64.66头。上述3种诱芯对严重危害橡胶树的对粒材小蠹和循胸材小蠹的诱捕效果尤为显著,对粒材小蠹和循胸材小蠹的诱捕数量占诱捕害虫总数的百分比分别为48.36%和47.89%、46.89%和40.48%、40.45%和40.24%。1~90 d的淀粉颗粒状缓释型诱芯和环糊精糊状缓释型诱芯对橡胶小蠹虫的诱捕效果无显著性变化,平均单日单个诱芯诱捕器诱捕虫数均在10头以下,诱捕效果差。上述结果表明,自制的(S)-(-)-小蠹烯醇海绵诱芯、无纺布型诱芯和储藏瓶型诱芯均可广泛用于有效绿色监控橡胶小蠹虫,海绵诱芯、无纺布型诱芯的田间有效期为60 d,储藏瓶型诱芯的田间有效期为30 d。  相似文献   

10.
杂交油菜云油杂10号高产栽培因子的优化   总被引:1,自引:0,他引:1  
为了探讨在云南省油菜生产中种植密度(X1)、氮肥(纯氮,X2)、磷肥(五氧化二磷,X3)、钾肥(氧化钾,X4)、硼肥(有效硼,X5)5个栽培因子对甘蓝型双低油菜云油杂10号产量的影响,并进一步优化各栽培因子,本文采用五元二次正交旋转组合设计,建立了油菜产量优化数学模型:Y=246.15 +12.70X2 +7.00 X3-6.26X12-9.81 X22-5.07X32-10.56X1X2-6.37X3X4。结果表明各因素对云油杂10号产量的影响大小顺序依次为氮肥、磷肥、种植密度、硼肥、钾肥。其中种植密度、氮肥、磷肥与产量的关系均呈开口向下的抛物线,种植密度过大或过小,施氮、磷肥过多或过少都会对油菜产量造成影响。种植密度与氮肥、磷肥与钾肥交互作用对油菜产量有显著影响,在种植密度10.5~22.5万株/hm2、施纯氮0~207kg/hm2、施五氧化二磷0~96kg/hm2、施氧化钾0~120kg/hm2时,两因子之间均为正相互作用。频率分析结果表明,油菜产量大于3 900kg/hm2的优化栽培措施为种植密度15.48~17.94万株/hm2、纯N、五氧化二磷、氧化钾、有效硼施用量分别为360.2~387.1、170.0~181.4、15.0~30.0、1.46~1.84kg/hm2。  相似文献   

11.
调查统计发现,广东车八岭国家级自然保护区共有保健植物49科79属110种,其中裸子植物3科3属4种,双子叶植物41科69属97种,单子叶植物5科7属9种。文中根据习性和利用部位对其进行了分类,还结合保护区的实际情况提出了开发利用保健植物的建议。  相似文献   

12.
广东省惠州市东湖花园的植物资源调查结果表明:该小区的植物种类可分为55科102种, 其中蕨类植物3科3种,裸子植物5科5种,被子植物47科94种,被子植物中双子叶植物36科61种,单子叶植物11科33种;分析其植物配置现状,并就其今后园林规划中植物的配置提出建议。  相似文献   

13.
我国北方地区玉米根寄生线虫的种类鉴定研究   总被引:3,自引:1,他引:3  
1992~1995年对采自辽宁、吉林、黑龙江、内蒙古、河北、山东和江苏等省的玉米根寄生线虫进行分类鉴定研究,共鉴定出14属的36种线虫。即:丝尾垫刃线虫属Filenchus1个种;短体线虫属Pratylenchus10个种;拟短体线虫属Pratylenchoides1个种;矮化线虫属TylenchorhyNchus3个种;纽带线虫属Hoplolaimus3个种;螺旋线虫属Helicolylenchus4个种;盘旋线虫属相似文献   

14.

Background

Niche theory predicts that human disturbance should influence the assembly of communities, favouring functionally homogeneous communities dominated by few but widespread generalists. The decline and loss of specialists leaves communities with species that are functionally more similar. Evenness of species occupancy declines, such that species become either widespread of rare. These patterns have often been observed, but it is unclear if they are a general result of human disturbance or specific to communities that are rich in species, in complex, spatially heterogeneous environments where the problem has often been investigated. We therefore tested whether human disturbance impacts dominance/evenness of species occupancy in communities, specialism/generalism of species, and functional biotic homogenization in the spatially relatively homogeneous, species poor boreal forest region of Alberta, Canada. We investigated 371 boreal vascular plant communities varying 0 – 100% in proportion of human land use.

Results

Rank species occupancy curves revealed high species dominance regardless of disturbance: within any disturbance class a few species occupied nearly every site and most species were found in a low proportion of sites. However, species were more widespread and displayed more even occupancy in intermediately disturbed communities than among communities of either low or high disturbance. We defined specialists and generalists based on turnover in co-occupants and thereby assessed impacts of human disturbance on specialization of species and community homogenization. Generalists were not disproportionately found at higher disturbance sites, and did not occupy more sites. Communities with greater human disturbance were not more functionally homogeneous; they did not harbor communities with more generalists.

Conclusions

We unexpectedly did not observe strong linkages between species specialism/generalism and disturbance, nor between community homogenization and disturbance. These results contrast previous findings in more species rich, complex or spatially heterogeneous systems and ecological models. We suggest that broad occupancy-based intercommunity patterns are insensitive to human land use extent in boreal vascular plants, perhaps because of ubiquity of generalists, low species richness, and history of natural disturbance. The poor sensitivity of these metrics to disturbance presents challenges for monitoring and managing impacts to biodiversity in this region.  相似文献   

15.
观赏水草是水族箱的重要组成部分,其消费日渐成熟。淘宝在售的观赏水草有淡水观赏水草17科22属96种(含品种),海水观赏水草10科11属13种。其中,淡水观赏水草有20种只具有观赏用途,占总种数的20.83%;76种兼具稳定水质和观赏用途,占总种数的79.17%。海水观赏水草有3种只具有观赏用途,2种兼具观赏和净化水质的用途,8种具有观赏、净化水质和饲用3种用途。淡水种类绝大部分都是外来种,仅13种在中国有分布,仅占总种数的13.54%;海水种类由于海水传播的特殊性,均为全球广布种或东太平洋种类。  相似文献   

16.
海南岛兰花种质资源考察报告   总被引:4,自引:1,他引:4  
对海南岛15个县(市)不同生态类型区兰花种质资源进行了全面的考察,共搜集了野生兰57属161种(变种、型),栽培兰14属(剔除与野生种重复)50余个品种,其中海南特有种21个,东亚特有属8个,海南新记录属6个,海南新记录种13个,保存活种质180余种(品种、型),10多种野生兰有观赏价值。通过实地考察,基本摸清了海南岛兰花种质的分布(水平分布和垂直分布)、生态环境、多度、花果期及形态特征等情况。  相似文献   

17.
Upland hay meadows conforming to MG3 in the National Vegetation Classification of the UK are a rare habitat in Britain and are largely confined to upland valleys in northern England. Agricultural intensification, particularly ploughing and reseeding and a shift from hay‐making to silage production over the last 50 years, has resulted in large losses of species‐rich upland hay meadows. Remaining species‐rich meadows have been the focus of much nature conservation effort resulting in many of the species‐rich sites being protected by statutory designations or through voluntary agri‐environment scheme agreements. Research and monitoring has tended to confirm that species richness is maximized by management involving spring and autumn grazing, a mid‐July hay cut, no inorganic fertilizer and possibly low levels of farmyard manure. Deviations from this regime result in a loss of species richness. Restoration of semi‐improved grassland to swards resembling species‐rich MG3 also requires a similar regime but is also dependent on the introduction of seed of appropriate species. The role of Rhinanthus minor as a tool for manipulating meadow biodiversity during restoration management is discussed. Suggestions for future research are outlined.  相似文献   

18.

Background

Using phylogenies in community ecology is now commonplace, but typically, studies assume and test for a single common phylogenetic signal for all species in a community, at a given scale. A possibility that remains little-explored is that species differing in demographic or ecological attributes, or facing different selective pressures, show different community phylogenetic patterns, even within the same communities. Here I compare community phylogenetic patterns for fire-killed and fire-resistant Banksia species in the fire-prone shrublands of southwest Australia.

Results

Using new Bayesian phylogenies of Banksia, together with ecological trait data and abundance data from 24 field sites, I find that fire regeneration mode influences the phylogenetic and phenotypic signal of species co-occurrence patterns. Fire-killed species (reseeders) show patterns of phylogenetic and phenotypic repulsion consistent with competition-driven niche differentiation, but there are no such patterns for fire-resistant species (resprouters). For pairs of species that differ in fire response, co-occurrence is mediated by environmental filtering based on similarity in edaphic preferences.

Conclusions

These results suggest that it may be simplistic to characterize an entire community by a single structuring process, such as competition or environmental filtering. For this reason, community analyses based on pairwise species co-occurrence patterns may be more informative than those based on whole-community structure metrics.  相似文献   

19.
部分栽培稻和野生稻种子谷蛋白的电泳分析   总被引:7,自引:0,他引:7  
 供试的不同属、不同种及不同生态型的水稻材料的种子各蛋白经SDS-PAGE电泳后可分辨为3类多肽,分子量分别为l8~23 kDa.30~36 kDa和49~100 kDa。不同属的材料各蛋白带型明显不同; 同属内基因组相同或相近种的各蛋白有特征多肽,AA基因组的有约Mt.50 kDa的多肽2~3条,CCDD基因组的有约Mt.23 kDa的多肽一条;籼型和粳型稻间带型存在差异,而爪哇稻、粳稻、籼稻间,前二者略近,并以粳型陆稻与爪哇稻最近似。同一生态型的各品种,除细弱带偶尔有差异外,带型基本一致。由此可见,水稻各蛋白电泳分析作为方法之一, 对于属间和稻属内各种及种内分类是有意义的。  相似文献   

20.

Background

Phytoplankton species identification and counting is a crucial step of water quality assessment. Especially drinking water reservoirs, bathing and ballast water need to be regularly monitored for harmful species. In times of multiple environmental threats like eutrophication, climate warming and introduction of invasive species more intensive monitoring would be helpful to develop adequate measures. However, traditional methods such as microscopic counting by experts or high throughput flow cytometry based on scattering and fluorescence signals are either too time-consuming or inaccurate for species identification tasks. The combination of high qualitative microscopy with high throughput and latest development in machine learning techniques can overcome this hurdle.

Results

In this study, image based cytometry was used to collect ~?47,000 images for brightfield and Chl a fluorescence at 60× magnification for nine common freshwater species of nano- and micro-phytoplankton. A deep neuronal network trained on these images was applied to identify the species and the corresponding life cycle stage during the batch cultivation. The results show the high potential of this approach, where species identity and their respective life cycle stage could be predicted with a high accuracy of 97%.

Conclusions

These findings could pave the way for reliable and fast phytoplankton species determination of indicator species as a crucial step in water quality assessment.
  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号