腰果园茶角盲蝽为害分布型及防治策略的研究

通过对腰果园茶角盲蝽(Helopeltis fasciaticollis Popplius)种群消长过程为害分布型的测定及拟合其生长指数曲线,发现一年中其种群建立始于8—9月份,翌年1月份前,虫口增长缓慢,2月初起,虫口急剧增加,4—5月份是为害高峰期,6—7月份虫口自然减少,其空间构型除高峰期外,均属聚集分布,早期为Neyman核心分布。从虫口增长速度及空间构型来看,11—1月份是种群为害扩展的临界期,也是化学防治的最有利时机。为此,我们采取了定期全面调查,及早发现中心虫株(区),局部喷药(挑治)的策略,从而以最低的防治成本获得最佳的经济效益,把整个花、果期的盲蝽为害率控制在5%以下。每年收果后修枝和适当疏伐也是减轻茶角盲蝽为害的重要手段。     

咖啡黑小蠹的发生规律及药剂防治研究

咖啡黑小蠢是近年在兴隆华侨农场严重危害中粒种咖啡的重要害虫。据1989年对4—5年生咖啡树调查,植株受害率100％,枝条受害率29.7—82.5％,虫害枯枝率7.65—17.8％。该虫以雌成虫钻蛀咖啡枝条为害,幼虫和成虫取食蛀道壁上的真菌菌丝。田间种群数量通常在3月上旬开始剧增,3月中下旬为高峰期,7月至10月田间虫口极少,11月以后逐渐有虫口及虫枯枝出现。温度是影响虫口波动的主要因素。2.5％溴氰菊酶、25％杀虫双、40％乐菊酯各兑水1000倍对成虫直接触杀效果显著,死亡率均为100％。48％乐斯本、40％氧化乐果400—800倍液等12种杀虫剂田间喷雾对咖啡枝条蛀洞内的成虫、蛹、幼虫防效均不明显。     

腰果云翅斑螟的初步研究

腰果云翅斑螟(Nephop teryx sp.)是我国腰果的新害虫,其幼虫蛀食坚果及果梨,据1985年调查最高为害率达60.2％。幼嫩坚果被蛀食后,种仁无法形成,最后导致干枯;较老的坚果被蛀食后,种仁扭曲,降低商品价值;果梨被蛀食后,引起腐烂。腰果云翅斑螟一代需时30～34天。此虫的发生与腰果结果期相吻合。成虫白天躲于枝条上,其活动盛期在傍晚及清晨;一头雌成虫最高产卵量125粒,卵产于果腹、果蒂、果柄及花萼萼片处;幼虫5龄;化蛹场所主要在植株冠幅下离土表约1厘米深的土中。建议喷射敌敌畏或杀螟松并结合摘除带虫果及收集落地被害果,挖掘蛹等综合措施对此虫进行防治。     

茶黄蓟马的生物学特性与防治

茶黄蓟马(Scirtothrips dorsalis)Hood是华南茶树上的重要害虫。一年可发生10—11代。5—10月份,11—21天便可完成一代,虫口高峰出现在9—10月,无明显越冬,成虫寿命7—25天,若虫期1—2龄4—10天,预蛹和蛹期2—6天;每雌产卵量平均35—62粒。成虫活跃,无趋光性,对黄色板和绿色板有正趋性。大叶种茶树虫口数量较多。少雨、干燥有利此虫发生。及时分批采摘和用高效灭百可或速灭杀丁6000倍液、喹硫磷1000倍液、水胺硫磷1500倍液对防治本虫有较好效果。     

茶硬胶蚧形态、习性及防治的研究

茶硬胶蚧[Tachardina theae(Green et Menn)]是近年来在部分茶区发生蔓延的一种茶树介壳虫,危害后招致严重煤病,造茶叶减产,甚至茶树枯死。茶硬胶蚧在浙江一年发生一代,以雌成虫在茶树枝杆上越冬,翌年5月下旬盛见若虫。各虫态历期。雌成虫8个月,雄成虫最长一天,若虫60天     

腰果云翅斑螟幼虫发生动态及空间分布型研究

对腰果云翅斑螟(Nephopteryx sp.)幼虫发生动态及空间分布型进行研究.结果表明,腰果果实被害率和果虫量的发生动态曲线均为双峰型,其高峰期均分别出现在中果期和末果期.株虫量的发生动态曲线为单峰型,其高峰期出现在盛果期.不同结果期对腰果云翅斑螟幼虫以及被害果实在腰果植株上的空间分布均无影响,均呈聚集分布.不同结...     

禾谷孢囊线虫的田间侵染规律及垂直分布研究

为了解禾谷孢囊线虫(CCN)在小麦田间的侵染规律和分布动态,在2010-2012年的两个冬小麦生育周期里,定点调查CCN(Heterodera avenae)江苏沛县群体的田间生活史及不同虫态的数量.结果表明,在小麦生长季节中CCN只能完成一代生活史;小麦越冬前有少量二龄幼虫(J2)孵化,能侵入根系,但不能正常发育;返青期小麦的根围土壤中出现J2孵化高峰,大量侵入根系后,至抽穗期完成发育,在根系上形成肉眼可见的白色雌虫,在根内及土中可见少量雄虫;小麦成熟收获期,白色雌虫开始变褐形成孢囊,落入土中越夏.从田间垂直分布调查结果看,田间孢囊主要分布在土表下0～10 cm土层,孢囊线虫孵化的J2也主要分布在0～10 cm土层中,并且在返青期出现高峰,这与CCN的田间侵染规律相吻合.     

性诱剂在棉虫测报上的应用

性诱剂是雌虫在性成熟后释放出来的一种引诱雄虫的化学活性物质,所以在田间设置一定数量的诱捕器,可以消灭大部分雄虫,藉以达到防治害虫的目的,或在田间大量释放信息素的气味,破坏雌雄虫间的交配信息,致使雌雄虫间无法交尾,繁延后代,达到防治的目的。性诱剂具有灵敏度高,选     

一代玉米螟的防治措施

玉米螟是全球性大害虫,食性杂,为害植物达200种以上,尤以玉米为最重。一般为害较轻年份,产量损失5%～10%,为害较重年份产量损失可达10%～20%,玉米螟不仅为害严重,而且防治困难。目前还没有一个非常理想的防治方法,只能通过综合防治来控制玉米螟的为害程度。玉米螟防治途径主要有三条:一是消灭玉米越冬虫源;二是消灭玉米螟成虫;三是消灭玉米螟田间幼虫。1　消灭玉米螟越冬虫源把玉米螟越冬幼虫消灭在越冬寄主之中,可收到事半功倍的效果。因为一头越冬幼虫羽化后雌蛾在田间可产卵10～20块,约300～600粒,故消灭越冬幼虫一对等于在田间消灭240～…     

室内不接触农药的褐飞虱种群对农药的敏感性和对水稻品种的适应性

在室内研究了经连续多代未接触农药的田间褐飞虱种群在不同抗性水稻品种上的生态适应性。结果表明,田间种群经室内连续多代未接触农药饲养后其对吡虫啉的抗性从F1代的359.94倍降到F14代的6.50倍,其中F4到F8下降快,F10到F14代基本趋于稳定;而其对毒死蜱的抗性下降趋于平缓,从F1代的9.90倍降到F14代的5.94倍。若虫历期和雌成虫体质量均显著受水稻品种和连续饲养代别数及代别×品种的影响,而若虫存活率只受代别数影响。雄虫中短翅型比例受代别和代别×品种的影响,而雌虫中短翅型比例不受代别、品种以及代别×品种的影响。在三种水稻品种上褐飞虱若虫历期均随着代别增加而延长,其中F1和F4的若虫历期较短,其余均较长。在感虫水稻品种TN1上的雌虫若虫历期明显短于在抗虫品种IR26和IR36上的历期,TN1上的雌成虫体质量明显比抗虫品种上的高。这些结果表明褐飞虱种群不接触农药后其对农药的敏感性上升,但对水稻抗性品种IR26和IR36的适应性并未增强。这些结果对于合理使用农药和水稻抗性品种治理褐飞虱具有重要意义。     

腰果叶片氮磷钾年周期变化及再吸收效率

以6龄腰果无性系FL30为对象,采集全年12个月腰果成熟叶片样品,分析腰果叶片N、P、K年周期变化规律;并采集腰果衰老叶片样品,分析腰果树N、P、K再吸收效率.结果表明:腰果叶片N、P、K含量随生育期的改变而变化;叶片N含量从抽梢期至果实成熟呈上升趋势,果实成熟后明显下降,休眠期叶片N含量变化不大;叶片P含量从抽梢期至初果期总体呈下降趋势,初果期至休眠期则呈上升趋势；叶片N/P呈现出与N相似的年周期变化规律;叶片K含量在抽梢期呈下降趋势,初花期骤然上升,盛花坐果期继续缓慢上升,果实生长期至休眠期则呈下降趋势;腰果成熟叶片N、P、K含量显著高于衰老叶片,N、P、K再吸收率较高,再吸收效率顺序为REp＞REN＞REk.     

作物及热带作物病虫害数据库的研制和建立

通用的“作物病虫害数据库管理系统（ＰＥＳＴＢＡＳＥ２．１）”和用此系统建立的“热带作物病虫害数据库管理系统”的主要信息项有：各种寄主作物的种类、种植利用，各种病虫的分类地位、地理分布、检疫情况、生物学特性、危害症状、发生规律、天敌、防治方法和农药信息。所建热带作物病虫害数据库管理信息系统中已录用１０００余篇有关献或专中的相关信息，涉及的作用种类有：橡胶、咖啡、可可、胡椒、油棕、椰子、腰果、热带     

Within-Canopy Distribution of Stenoma catenifer (Lepidoptera: Elachistidae) Infestation in Avocado Orchards

Native to the neotropics, the avocado seed moth Stenoma catenifer Walsingham (Lepidoptera: Elachistidae) is a specialist pest of the family Lauraceae and considered one of the most important pests of avocados worldwide. However, little is known regarding its spatial distribution within a single tree. Therefore, we designed a study to evaluate the effects of canopy height and aspect (i.e., side of the tree) on fruit infestation by S. catenifer larvae in avocados. The study was conducted in three commercial organic avocado orchards located in São Paulo, Brazil. At each orchard, 40 fruit from 30 random trees were sampled weekly from October 2017 through February 2018, evaluating the number of fruits infested by S. catenifer larvae at three tree heights (bottom, middle, and top). In addition, fruits on the ground were also sampled. We also evaluated the effect of the side of the tree where the fruits were collected, i.e., whether they were on the side facing the east (sunrise) or the west (sunset). Within the avocado canopy, the level of fruit infestation by S. catenifer larvae was significantly higher at the top of the trees than in the middle and bottom. Fruit on the ground had lower levels of infestation than those on the tree canopy. The level of fruit infestation was also higher on the side of avocado trees facing the east (sunrise). Understanding the within-tree distribution of S. catenifer will help to better target monitoring and control activities against this pest in avocados.     

海南入境台湾果蔬危险性有害生物普查及其安全性评估

适应海南入境台湾果蔬产业健康、快速、可持续发展的需要,系统开展了海南入境台湾果蔬危险性有害生物普查,并采用PRA评估模型对17种外来入侵危险性有害生物进行了风险评估。2009～2010年考察发现,海南入境台湾果蔬以芒果、西瓜、哈密瓜、辣椒、番茄、莲雾、番木瓜和番石榴为主,主要分布在文昌、琼海、三亚、乐东、东方、昌江、澄迈、海口等农场和瓜菜生产基地,并且各瓜菜品种种植面积因市场价格影响年份间波动较大;调查共查获海南入境台湾果蔬危险性有害生物68种,包括害虫32种,病原微生物16种,杂草20种,其中外来入侵危险性有害生物17种;大面积严重发生与危害危险性有害生物25种;桔小实蝇、螺旋粉虱、烟粉虱、西瓜细菌性果斑病在海南均属于高度危险有害生物。上述结果为进一步开展海南入境台湾果蔬危险性有害生物监测预警与防控提供了前期工作基础。     

Identifying an Optimal Screen Mesh to Enable Augmentorium-Based Enhanced Biological Control of the Olive Fruit Fly Bactrocera oleae (Diptera: Tephritidae) and the Mediterranean Fruit Fly Ceratitis capitata (Diptera: Tephritidae)

The augmentorium is a cost-effective screened enclosure designed to receive fruits infested with insect pests, retain the pests inside but let their natural enemies escape to enhance biological control of pest populations. Screen selection is critical to ensure that an augmentorium is effective for a particular system. Here we tested five types of screens with a mini-augmentorium design and measured the escape of four insect species under laboratory conditions: the pests olive fruit fly Bactocera oleae (Rossi) (Diptera: Tephritidae) and Mediterranean fruit fly Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), and the parasitoids Psyttalia lounsburyi (Silvestri) (Hymenoptera: Braconidae) and Psyttalia ponerophaga (Silvestri) (Hymenoptera: Braconidae). The sex ratio of insects that escaped the screens was compared to the sex ratio of insects that could not escape. Results showed that one screen type (‘crystal mesh’) was the best for the purpose of designing a functional augmentorium: it retained 90% of B. oleae adults and 100% of C. capitata adults while letting 72% of Psyttalia lounsburyi adults and 94% of P. ponerophaga adults escape. The other screen types tested were suboptimal, either because they let too many flies freely escape or because they retained too many parasitoids. Sex ratio was almost always similar for insects that managed to escape the screens and insects that were retained, except for P. ponerophaga and the screen type ‘light mesh’. These results are promising for the development of a functional augmentorium against the olive fruit fly and further implementation against Mediterranean fruit fly.     

火龙果果实发育期间营养元素含量的变化

以红肉火龙果新品种‘紫红龙’为试验材料,研究果实发育期间鳞片、果皮、果肉中N（氮）、P（磷）、K（钾）、Ca（钙）、Mg（镁）、Fe（铁）、Zn（锌）、Mn（锰）、Cu（铜）、B（硼）营养元素含量的变化。结果表明：火龙果花后3 d鳞片和果肉K含量维持较高水平,之后呈下降趋势,果皮K含量在果实成熟时最高。在整个果实发育期间,K含量比其他营养元素的含量高。火龙果花后3 d果肉的Ca含量最高,在果实发育中,呈明显的下降趋势。从10种营养元素在鳞片、果皮和果肉生长发育中的变化规律来看,在幼果期,果实中多种元素的含量均处于最高水平,此后,随着幼果的快速增大,矿质元素含量逐渐下降。直至果实成熟期,各种矿质元素含量趋于稳定。     

海南岛的腰果害虫

本文记录了海南岛56种腰果害虫之分布及为害,并对其中的重要害虫腰果角盲蝽、脊胸天牛、咖啡胖天牛及腰果云翅斑螟的形态、生物学习性及防治作了记述。     

不同处理对桃形李采后病原菌的防治效果

桃形李采后极易发生病害,难以保鲜,为了控制桃形李采后病害的发生,通过对分离到的病原菌扩展青霉菌株(Penicillium expansum,TXL-01)进行形态学观察和对其它水果致病性试验,分别用硝普钠、葡萄籽提取物和NaHCO_3在PDA培养基上进行抑菌实验。结果表明:形态学观察发现致病菌菌丝有分枝和横隔膜,具帚形孢子囊,能产生大小不同的2种类型孢子;对多种水果侵染后均能致病,说明致病菌对宿主要求专一性不高;硝普钠和葡萄籽提取物只能在前3 d抑制病原菌的生长,但是在第4天以后与对照无明显差异;NaHCO_3浓度为0.10%和0.15%时,培养到第6天时能显著抑制病原菌生长;当NaHCO_3为0.2%时,培养到第12天时内还能抑制病原菌生长;再分别以0.10%、0.15%、0.20%NaHCO_3和0.20%NaHCO_3+1.0%壳聚糖(Chitosan)复合处理桃形李采后果实,发现0.20%NaHCO_3处理虽然也能减少果实腐烂率,但结合1.0%Chitosan涂膜处理对果实保鲜效果更好,可以显著抑制致病菌的发生,降低果实发病率,说明NaHCO_3和Chitosan复合处理可以应用于桃形李的采后保鲜。     

Histological development of the sunflower fruit pericarp as affected by pre- and early post-anthesis canopy shading

The dynamics of pericarp development compared to that of the embryo, as well as the effect of pre-anthesis and post-anthesis shading on pericarp histogenesis and dry weight dynamics of fruits from two sunflower (Helianthus annuus L.) hybrid cultivars along three capitulum positions, peripheral, mid and central were studied. During fruit formation, the cell division phase of the carpel takes place before anthesis. Eight days after anthesis the pericarp reached its final size, while its cell wall's sclerification was almost complete 13 days after anthesis. Pre-anthesis shading affected the carpel cell division period reducing (17–33%) the number of pericarp middle layer strata and increased the thickenings of the cell wall of the mid (19%) and central (33–63%) fruits. In central fruits, the dry weight accumulation period was reduced. In contrast, post-anthesis shading reduced both the cell wall thickness (16–64%) and the number (38–58%) of pericarp middle layer sclerified strata of fruits in the three positions of the capitulum. In the mid and central fruits, the dry weight accumulation period extended 11–16 and 3–4 days, respectively, over those of the control. Both shading treatments produced thinner and lighter pericarps, but with different anatomical features that were associated with differences in the efficiency of use of the fruit for industrial oil extraction.