湖南省茶树害虫地理区划分析

通过湖南省茶树害虫的系统调查,查明湖南省茶树害虫(害螨)共302种,根据其在湖南省各地(市)的分布,编成"0,1"分布数据表,然后进行聚类分析.根据聚类结果,参考地理、气候、茶树的种植历史和种植面积以及其他动物类群方面的研究和前人的工作,把湖南省茶树害虫分成4个区:湘北环湖平原丘岗区,湘中、湘东丘陵区,湘西山区,湘南山地丘陵区,并分别叙述了各区的特点.     

拟除虫菊酯类农药对茶树害虫的生物活性与残留降解

本文报道了溴氰菊酯、联苯菊酯、氯氰菊酯、顺式氯氰菊酯、杀灭菊酯、功夫菊酯和二氯苯醚菊酯等七种拟除虫菊酯类农药对茶树主要害虫的杀虫效果和在茶树叶片上的降解动态试验结果.上述七种拟除虫菊酯类农药对鳞翅目茶树害虫的幼虫都具有极高的毒力,但对其他害虫的活性谱则表现有差异.它们在茶树芽梢上的降解速率常数为0.20—0.28天^-1,在茶树上的半衰期为2.5—3.5天,明显较有机磷农药稳定.在影响降解的因素中,挥发、热分解、雨水淋洗的作用不大,由茶梢生长稀释所起的作用较为明显.鲜叶中的农药残留在加工过程中的降解率为15—45%,平均20%,远低于有机磷农药.成茶中的残留农药在泡茶过程中由于他们的低水溶性,因此浸出率很低,一般仅有1—4.5%.     

果茶新害虫—闽鸠蝠蛾初步研究（鳞翅目：蝙蝠蛾科）

闽鸠蝠蛾Phassus minanus Yang是近几年在中国福建省新发现的一种害虫．为害茶和柑桔．枇把等果树．经北京农业大学杨集昆教授鉴定为一新种,并以福建省的简称“闽”(Min)为其种名．作于1980年在福建省三明市枇杷树上首先发现,后来又在1981和1984年相继在柑桔和茶树上也发现其为害．现今已成为福建北部山地果、茶园一种颇为重要的虫害．闽鸠蝠蛾一个世代经历两年。幼虫在树干基部作环状蛀害,可致被害果茶树．全株枯死．本记述此虫发现经过、分布．寄主植物．为害习性和形态特征,末提出了关于防治方法的讨论．     

茶树钻蛀性枝梗害虫的发生与防治

安溪县位于福建省东南部,因其山地丘陵以及高海拔所形成的特定气候条件,适宜茶树生长。该县产茶历史悠久,常年茶叶产量占全省第一位,尤其是优质乌龙茶,名扬海内外,年产值超亿元,是该县农业一大支柱产业。但由于老茶园多,钻蛀性枝梗害虫发生为害逐年加重,部分茶园几乎丛丛有虫害枝,存在树死园毁的危机。为此笔者自1994年以来,对此类害虫的发生为害作了调查观察和防治试验,现将结果整理如下。     

《中国茶树害虫及其无公害治理》

由安徽农业大学张汉鹄教授与湖南农业大学谭济才教授编著,安徽科学技术出版社出版,精装,53万字。共10章,分别阐述了我国茶树昆虫区系分布,茶树害虫来源、发生与种群演替,茶园生物群落,茶园天敌资源及其对害虫的自然控制,茶园害虫生态控制与无公害茶叶生产,国内常见100余种茶树害虫的发生规律与无公害防治技术,还特约有各生产茶区专家的相关论述。书附有一批彩图．中国荣树有害昆虫名录,中国茶树害虫天敌名录,     

频振式杀虫灯在茶树害虫测报、防治中的应用

应用佳多频振式杀虫灯进行了茶树害虫的预测预报和防治试验。结果表明,该灯对茶园中的茶细蛾Caloptiliatheivora(walsingham)、茶毛虫EuproctispseudoconspersaStrand、斜纹夜蛾Prodenialitura(Fabricius)等茶树主要害虫有明显的诱集作用;同时,根据害虫成虫诱集时间、数量与面上生育期观察,其动态变化基本一致,可以用于幼虫的发生期、发生量预报,在面上应用频振式杀虫灯对3种的防治试验中取得明显的效果。认为该灯是一种安全、经济、有效、无污染的茶树害虫预测预报和防治工具。     

植食性昆虫学习行为与害虫治理的关系

植食性昆虫的学习行为一般具有习惯性反应、厌恶性学习、联系性学习、敏感性反应、嗜好性诱导几种类型,它们对害虫防治方法的效果具有重要影响。害虫通过嗜好性诱导对栖境中大面积单作农作物造成更大的危害,通过联系性学习可对诱虫植物的效果产生积极或消极的影响。害虫对驱避剂或杀虫剂等产生习惯性反应可降低其防治效果。害虫对寄主植物驱避抗性产生习惯性学习就会加重对作物的为害,产生厌恶性学习则有利于对作物的保护。利用害虫的联系性学习行为,释放前让不育雄虫学习自然交配场所的环境刺激,可增强通过释放不育雄虫控制害虫的防治效果。了解植食性昆虫学习行为对害虫治理的影响有助于研究和发展有效的栖境调控、行为调控等策略和方法。     

福建省茶树害虫名录

笔于1974—1976年与1990—1992年在福建省近40个县市(包括武夷山、梅花山自然保护区)进行茶树害虫的调查。现据调查所得的材料,连同过去积累的调查记录和献资料整理成这一名录．     

茶丽纹象甲为害诱导的茶树防御反应分析

基于转录组测序,获得了茶树新梢叶片被茶丽纹象甲为害前后的差异基因表达谱,并从信号监测与转导、转录因子、次生代谢物生成等方面分析了相关基因的表达变化情况,为进一步研究茶丽纹象甲为害诱导的茶树防御机制奠定基础。结果表明:(1)茶丽纹象甲为害茶树新梢叶片后共检测到显著上调表达基因309个,显著下调表达基因297个,这些显著差异表达基因共分成23类。(2)检测到信号监测与转导过程中合计17个单基因上调表达2.0～2.8倍,包括富含亮氨酸重复序列的类受体蛋白激酶基因、促分裂原活化蛋白激酶级联信号系统蛋白激酶基因、茉莉酸信号通路基因、钙离子信号基因、水杨酸代谢通路基因;检测到21个转录因子单基因上调表达1.8～2.8倍,包括bHLH、WRKY、bZIP、MYB、UAF等转录因子;检测到苯丙类、类黄酮及萜类物质代谢过程中合计8个单基因上调表达2.1～2.5倍,包括苯丙酮酸互变异构酶基因、肉桂酰辅酶A还原酶基因、二氢黄酮醇还原酶基因、花色素还原酶基因、法尼基二磷酸合成酶基因、法尼醇脱氢酶基因。研究认为,茶丽纹象甲为害诱导信号转导、转录因子及次生代谢过程中的基因增量表达以机械损伤作用为主,昆虫口腔分泌物对这些基因的诱导表达具有协同促进作用。     

四种为害茶树的簔蛾幼虫的识别

蓑蛾科为害茶树的种类甚多,其中分布较普遍,为害较重的有如下四种: 1.茶蓑蛾Mahasena minuscula Butler 2.褐蓑蛾Mahasena colona Sonan 3.茶小蓑蛾Acanthopsyche sp. 4.大蓑蛾Claina pryeri Leech 茶蓑蛾是杂食性害虫,除为害茶外,桃、李、柑桔、枇杷、梅以及侧柏、紫荆等也会被害,在我国茶区中是一种较重要的局部为害的害虫,被害茶园茶树几乎没     

外源茉莉酸和茉莉酸甲酯诱导植物抗虫作用及其机理

综述了茉莉酸(jasmonic acid, JA)和茉莉酸甲酯(methyl jasmo nate, MJA)的分子结构和应用其诱导的植物抗虫作用及其机制。植物受外源茉莉酸或茉莉酸甲酯刺激后,一条反应途径是由硬脂酸途径激活防御基因,另一条途径是直接激活防御基因。防御基因激活后导致代谢途径重新配置,并可能诱导植物产生下列4种效应：（1）直接防御,即植物产生对害虫有毒的物质、抗营养和抗消化的酶类,或具驱避性和妨碍行为作用的化合物;（2）间接防御,即产生吸引天敌的挥发物;（3）不防御,即无防御反应;（4）负防御,即产生吸引害虫的挥发物。     

Parasitism by Cuscuta pentagona attenuates host plant defenses against insect herbivores

Considerable research has examined plant responses to concurrent attack by herbivores and pathogens, but the effects of attack by parasitic plants, another important class of plant-feeding organisms, on plant defenses against other enemies has not been explored. We investigated how attack by the parasitic plant Cuscuta pentagona impacted tomato (Solanum lycopersicum) defenses against the chewing insect beet armyworm (Spodoptera exigua; BAW). In response to insect feeding, C. pentagona-infested (parasitized) tomato plants produced only one-third of the antiherbivore phytohormone jasmonic acid (JA) produced by unparasitized plants. Similarly, parasitized tomato, in contrast to unparasitized plants, failed to emit herbivore-induced volatiles after 3 d of BAW feeding. Although parasitism impaired antiherbivore defenses, BAW growth was slower on parasitized tomato leaves. Vines of C. pentagona did not translocate JA from BAW-infested plants: amounts of JA in parasite vines grown on caterpillar-fed and control plants were similar. Parasitized plants generally contained more salicylic acid (SA), which can inhibit JA in some systems. Parasitized mutant (NahG) tomato plants deficient in SA produced more JA in response to insect feeding than parasitized wild-type plants, further suggesting cross talk between the SA and JA defense signaling pathways. However, JA induction by BAW was still reduced in parasitized compared to unparasitized NahG, implying that other factors must be involved. We found that parasitized plants were capable of producing induced volatiles when experimentally treated with JA, indicating that resource depletion by the parasite does not fully explain the observed attenuation of volatile response to herbivore feeding. Collectively, these findings show that parasitic plants can have important consequences for host plant defense against herbivores.     

Synergistic interactions between volicitin,jasmonic acid and ethylene mediate insect-induced volatile emission in Zea mays

Plants display differential responses following mechanical damage and insect herbivory. Both caterpillar attack and the application of caterpillar oral secretions (OS) to wounded leaves stimulates volatile emission above mechanical damage alone. Volicitin ( N- 17-hydroxylinolenoyl- l -glutamine), present in beet armyworm (BAW, Spodoptera exigua ) OS, is a powerful elicitor of volatiles in excised maize seedlings ( Zea mays cv. Delprim). We consider some of the mechanistic differences between wounding and insect herbivory in maize by examining the activity of volicitin, changes in jasmonic acid (JA) levels, and volatile emission from both intact plant and excised leaf bioassays. Compared to mechanical damage alone, volicitin stimulated increases in both JA levels and sesquiterpene volatiles when applied to intact plants. In a bioassay comparison, excised leaves were more sensitive and produced far greater volatile responses than intact plants following applications of both volicitin and JA. In the excised leaf bioassay, volicitin applications (10–500 pmol) to wounded leaves resulted in dose dependent JA increases and a direct positive relationship between JA and sesquiterpene volatile emission. Interestingly, volicitin-induced JA levels did not differ between intact and excised bioassays, suggesting a possible interaction of JA with other regulatory signals in excised plants. In addition to JA, insect herbivory is known to stimulate the production of ethylene. Significant increases in ethylene were induced only by BAW herbivory and not by either wounding or volicitin treatments. Using intact plant bioassays, ethylene (at 1 µl l⁻¹ or less) greatly promoted volatile emission induced by volicitin and JA but not mechanical damage alone. For intact plants, wounding, elicitor-induced JA and insect-induced ethylene appear to be important interacting components in the stimulation of insect-induced volatile emission.     

The rice hydroperoxide lyase OsHPL3 functions in defense responses by modulating the oxylipin pathway

As important signal molecules, jasmonates (JAs) and green leaf volatiles (GLVs) play diverse roles in plant defense responses against insect pests and pathogens. However, how plants employ their specific defense responses by modulating the levels of JA and GLVs remains unclear. Here, we describe identification of a role for the rice HPL3 gene, which encodes a hydroperoxide lyase (HPL), OsHPL3/CYP74B2, in mediating plant‐specific defense responses. The loss‐of‐function mutant hpl3‐1 produced disease‐resembling lesions spreading through the whole leaves. A biochemical assay revealed that OsHPL3 possesses intrinsic HPL activity, hydrolyzing hydroperoxylinolenic acid to produce GLVs. The hpl3‐1 plants exhibited enhanced induction of JA, trypsin proteinase inhibitors and other volatiles, but decreased levels of GLVs including (Z)‐3‐hexen‐1‐ol. OsHPL3 positively modulates resistance to the rice brown planthopper [BPH, Nilaparvata lugens (Stål)] but negatively modulates resistance to the rice striped stem borer [SSB, Chilo suppressalis (Walker)]. Moreover, hpl3‐1 plants were more attractive to a BPH egg parasitoid, Anagrus nilaparvatae, than the wild‐type, most likely as a result of increased release of BPH‐induced volatiles. Interestingly, hpl3‐1 plants also showed increased resistance to bacterial blight (Xanthomonas oryzae pv. oryzae). Collectively, these results indicate that OsHPL3, by affecting the levels of JA, GLVs and other volatiles, modulates rice‐specific defense responses against different invaders.     

Transcriptomic characterization of gall tissue of Japanese elm tree (Ulmus davidiana var. japonica) induced by the aphid Tetraneura nigriabdominalis

Insect galls are abnormal plant tissues induced by parasitic insect(s) for use as their habitat. In previous work, we suggested that gall tissues induced by the aphid Tetraneura nigriabdominalis on Japanese elm trees are less responsive than leaf tissues to jasmonic acid (JA), which is involved in the production of volatile organic compounds as a typical defensive reaction of plants against attack by insect pests. A comprehensive analysis of gene expression by RNA sequencing indicated that the number of JA responsive genes was markedly lower in gall tissues than in leaf tissues. This suggests that gall tissues are mostly defective in JA signaling, although JA signaling is not entirely compromised in gall tissue. Gene ontology analysis sheds light on some stress-related unigenes with higher expression levels in gall tissues, suggesting that host plants sense aphids as a biotic stress but are defective in the JA-mediated defense response in gall tissues.     

Induced plant defense via volatile production is dependent on rhizobial symbiosis

Nitrogen-fixing rhizobia can substantially influence plant–herbivore interactions by altering plant chemical composition and food quality. However, the effects of rhizobia on plant volatiles, which serve as indirect and direct defenses against arthropod herbivores and as signals in defense-associated plant–plant and within-plant signaling, are still unstudied. We measured the release of jasmonic acid (JA)-induced volatiles of rhizobia-colonized and rhizobia-free lima bean plants (Fabaceae: Phaseolus lunatus L.) and tested effects of their respective bouquets of volatile organic compounds (VOCs) on a specialist insect herbivore (Mexican bean beetle; Coccinellidae: Epilachna varivestis Mulsant) in olfactometer choice trials. In a further experiment, we showed that VOC induction by JA reflects the plant responses to mechanical wounding and insect herbivory. Following induction with JA, rhizobia-colonized plants released significantly higher amounts of the shikimic acid-derived compounds, whereas the emission of compounds produced via the octadecanoid, mevalonate and non-mevalonate pathways was reduced. These changes affected the choice behavior of beetles as the preference of non-induced plants was much more pronounced for plants that were colonized by rhizobia. We showed that indole likely represents the causing agent for the observed repellent effects of jasmonic acid-induced VOCs of rhizobia-colonized lima bean plants. Our study demonstrates a rhizobia-triggered efficacy of induced plant defense via volatiles. Due to these findings, we interpret rhizobia as an integral part of legume defenses against herbivores.     

Constitutive activation of jasmonate signaling in an Arabidopsis mutant correlates with enhanced resistance to Erysiphe cichoracearum,Pseudomonas syringae,and Myzus persicae

In Arabidopsis spp., the jasmonate (JA) response pathway generally is required for defenses against necrotrophic pathogens and chewing insects, while the salicylic acid (SA) response pathway is generally required for specific, resistance (R) gene-mediated defenses against both biotrophic and necrotrophic pathogens. For example, SA-dependent defenses are required for resistance to the biotrophic fungal pathogen Erysiphe cichoracearum UCSC1 and the bacterial pathogen Pseudomonas syringae pv. maculicola, and also are expressed during response to the green peach aphid Myzus persicae. However, recent evidence indicates that the expression of JA-dependent defenses also may confer resistance to E. cichoracearum. To confirm and to extend this observation, we have compared the disease and pest resistance of wild-type Arabidopsis plants with that of the mutants coil, which is insensitive to JA, and cev1, which has constitutive JA signaling. Measurements of the colonization of these plants by E. cichoracearum, P. syringae pv. maculicola, and M. persicae indicated that activation of the JA signal pathway enhanced resistance, and was associated with the activation of JA-dependent defense genes and the suppression of SA-dependent defense genes. We conclude that JA and SA induce alternative defense pathways that can confer resistance to the same pathogens and pests.