广东省飞虱虫疠霉的初步研究

对在广东省昆虫病原真菌资源调查中发现的一种经常在褐飞虱种群中引发流行病的昆虫病原真菌进行了研究.经鉴定,该菌为飞虱虫疠霉(Pandora detphacis),并就其感染飞虱后对褐飞虱主要生化指标的影响以及该菌初生分生孢子萌发率进行了测定.为开发利用该菌防治褐飞虱提供科学依据.     

褐飞虱和白背飞虱在抗褐飞虱水稻品种上的行为反应

以ASD7、IR36、粳籼89(JX89)、Mudgo四个抗褐飞虱水稻品种和感性品种TN1为材料,比较了褐飞虱和白背飞虱在这些品种上的行为反应。褐飞虱对抗性品种表现出明显的非嗜好性。褐飞虱自4h、白背飞虱自8h以后,各品种上的着虫量与TN1差异显著,而其它各品种上的虫量无明显差异(Mudgo除外)。白背飞虱选择各抗性品种的百分率明显大于褐飞虱(Mudgo除外);同一水稻品种上的稻飞虱数量无时间上的规律性。两种稻飞虱在抗性品种和TN1上的取食量差异显著。取食同一品种时,白背飞虱在IR36、JX89上的取食量大于褐飞虱,且相互间差异显著。两种稻飞虱在四个抗性品种上的取食痕数量明显多于TN1;两种飞虱在ASD7和JX89上的取食痕数量差异显著,白背飞虱的数量明显少于褐飞虱。在所有水稻品种上的取食痕数量与取食量呈明显的负相关关系。     

农田及灯下飞虱群落考查

飞虱科昆虫种类多,均为植食性,有些种类如褐稻虱、白背飞虱是水稻重要害虫,但更多的种类对作物并不造成经济损失。相反,它们的存在,有利天敌生存和保持农田生物群落的生态平衡。因此,准确认识飞虱种类,对植保工作者大为必要。根据作者收集的广西飞虱标本和灯下飞虱群落系统考查、鉴定结果,现报导如下。 一、农田及灯下飞虱种类     

黄色粘虫板在1代灰飞虱监测中的应用研究

近年来,上海地区水稻条纹叶枯病呈大发生态势。准确监测该病传毒媒介灰飞虱对防控条纹叶枯病非常关键。以往灰飞虱的测报主要是采用测报灯,而测报灯容易受天气因素影响,导致数据缺失,影响测报的准确性。为此,于2007年至2011年开展了灰飞虱的黄板测报技术研究。5年试验结果显示,黄板对灰飞虱诱集能力强,在灰飞虱高峰日预测与测报灯结果一致,可应用于1代灰飞虱的测报。     

褐飞虱抗药性机理及其治理研究进展

褐飞虱是一种重要的农业害虫,其对许多杀虫剂都产生了抗药性。化学药剂的大量不合理使用是导致褐飞虱产生抗药性的主要原因。褐飞虱的抗药性机理主要包括代谢抗性和靶标抗性。本文对褐飞虱的抗药性机理进行了综述,并对该虫的抗性治理进行了探讨。褐飞虱的抗性治理策略应包括抗性监测、使用新型药剂、合理使用杀虫剂及抗虫品种等。     

湖南近三年褐飞虱发生规律研究

通过采用虫情测报灯和田间虫情系统调查相结合的方法,调查和分析了2008-2010年湖南4个调查圃褐飞虱田间种群动态。汉寿的测报灯下褐飞虱始见日早于其他3个调查圃;褐飞虱全年上灯量道县最小,汉寿最大,2008-2010年汉寿上灯量分别为89 469、81 641头/灯和33 137头/灯。2008-2010年汉寿早稻、晚稻褐飞虱发生量都比较大,分析认为早期褐飞虱迁入量大是导致汉寿褐飞虱种群数量大于其他三地的主要原因,同时由于2010年9月下旬的连续低温导致道县、临湘和宁乡晚稻后期褐飞虱成虫和高龄若虫数量下降。褐飞虱在湖南可发生不完全6代,褐飞虱以7月上、中旬和9月下旬至10月上旬虫口密度最大,对迟熟早稻、一季稻和双季晚稻危害最大。     

褐飞虱利它素及其与水稻品种的关系

本文主要研究了稻虱缨小蜂(Anagrus nilaparvatae Pang et Wang)寄主褐飞虱(Nilaparvata lugens(St(?)l))利它素的存在部位、抽提方法以及水稻品种对其蜜露中利它素活性的影响。结果表明:在褐飞虱的各虫态、蜜露及脱皮壳中均存在能引起稻虱缨小蜂触角搜索行为的接触性利它素;干燥蜜露中的利它素活性极显著地低于新鲜和湿润蜜露中的。用二氯甲烷、正己烷、乙醚、甲醇和丙酮均能有效地从褐飞虱若虫和雌成虫中提取利它素。水稻品种能对褐飞虱蜜露中的利它素活性产生明显影响。在测试的6个水稻品种中,取食浙852的褐飞虱蜜露中的利它素活性分别显著和极显著地比取食TN1和Nabeshi的褐飞虱蜜露中的高。     

杀虫剂诱导褐飞虱再猖獗的原因分析

杀虫剂诱导褐飞虱再猖獗的原因分析陈建明（浙江省农业科学院植保所杭州３１００２１）褐飞虱ＮｉｌａｐａｒｖａｔａＩｕｇｅｎｉｓＳｔａｌ是我国及许多亚洲国家当前水稻生产上的首要害虫之一。目前，在褐飞虱的综合治理中化学防治仍然是一项不可缺少的措施，不少稻区由...     

六种植物精油对褐飞虱和稻虱缨小蜂行为的影响

为研发基于植物精油的褐飞虱Nilaparvata lugens驱避剂和稻虱缨小蜂Anagrus nilaparvatae引诱剂,利用嗅觉仪测试了6种植物精油在不同浓度下对褐飞虱和稻虱缨小蜂的行为反应。结果表明,6种植物精油对褐飞虱和稻虱缨小蜂行为的影响具有种类差异性,不同植物精油对昆虫的行为影响有较大差异。此外,褐飞虱和稻虱缨小蜂对植物精油的嗅觉反应还与精油浓度有关,精油浓度范围在100～5 000 mg/L时,山楂油、白木香油、金银花油、肉桂油和鱼腥草油对褐飞虱雌成虫表现出明显的趋避效果,其中山楂油和金银花油的驱避效果最好,二者在100、500、1 000和5 000 mg/L这4个浓度下均能显著驱避褐飞虱。0.1 mg/L和1 mg/L浓度的山楂油、0.1 mg/L浓度的白木香油和1 mg/L浓度的丁香花蕾油对稻虱缨小蜂雌成虫有较强的吸引力。较高浓度10 mg/L的鱼腥草油对稻虱缨小蜂有明显的驱避性。表明植物精油可以明显地影响褐飞虱和稻虱缨小蜂的行为,可作为行为调控物在"推-拉"策略中防控褐飞虱。     

近年来我国水稻褐飞虱暴发原因及治理对策

本文从气象因素、水稻耕作制度因素及化学防治因素等方面分析了我国近年来水稻褐飞虱暴发成灾的原因。褐飞虱迁入足够的虫源基数是大发生的基础,适宜的气候条件是大发生的关键,而化学药剂的防效下降及其技术不到位则是暴发成灾的客观原因。最后,还讨论了褐飞虱的防治策略。     

Development of a New Semiselective Medium for Isolating Xanthomonas campestris pv. manihotis from Plant Material and Soil

ABSTRACT An effective control for bacterial blight of cassava (Manihot esculenta), caused by Xanthomonas campestris pv. manihotis, requires the use of non-contaminated cuttings and seeds. Using classical agar plating techniques for screening planting material for contamination has not been very successful because of the lack of a reliable semiselective agar medium. The pathogen grows slowly on general plating media and is easily overgrown by saprophytic bacteria during isolation from diseased plants. In an effort to develop a semiselective medium, the utilization of several carbon and nitrogen sources was studied. Results of these tests provided information used to design a basal medium allowing good growth of the target organism while suppressing growth of several common saprophytes. Additional selectivity was achieved by incorporating three antibiotics into the basal medium. The new semiselective agar medium, designated cefazolin trehalose agar (CTA) medium, contained (per liter) 3.0 g of K(2)HPO(4), 1.0 g of NaH(2)PO(4), 0.3 g of MgSO(4).7H(2)O, 1.0 g of NH(4)Cl, 9.0 g of D(+)-trehalose, 1.0 D(+)-glucose, 1.0 g of yeast extract, 0.025 g of cefazolin, 0.0012 g of lincomycin, 0.0025 g of phosphomycin, 0.25 g of cycloheximide, and 14.0 g of agar. In comparison to a starch-based semiselective medium (SXM), plating efficiencies using pure cultures of 10 strains of X. campestris pv. manihotis were significantly higher on CTA, with an average of 85 and 50%, respectively. Likewise, isolation and recovery of X. campestris pv. manihotis from infected cassava leaves and contaminated soil were much higher on CTA than on SXM agar. When X. campestris pv. manihotis occurs in high concentrations in diseased tissue, the standard yeast trehalose glucose agar medium supplemented with 250 mug of cycloheximide per ml appears to be satisfactory. The newly developed CTA medium should prove useful for control strategies to identify and remove infected planting material of cassava, as well as for basic ecological studies of the pathogen.     

改良的L-15培养基对鳞翅目昆虫细胞生长和芹菜夜蛾核型多角体病毒增殖的影响

4种鳞翅目昆虫细胞系SL-ZSU-1、TnH5、Sf9和Ha-AM1都不能在L-15 5?S或L-15 350mg/L脯氨酸 5?S(L-15-P,pH6.5)的培养基中生长,但是都可以在L-15 3g/L水解乳蛋白 3g/L酵母提取物 1g/L葡萄糖 5?S(L-15-LYG)、L-15 350mg/L脯氨酸 1g/L葡萄糖 5?S(L-15-PG)、L-15 1g/L葡萄糖 5?Sa(L-15-G,pH6.5)的培养基中生长。细胞从TNM-FH 5?S(pH6.5)培养基中转入上述培养基后,适应期的长短相差较大。转入L-15-LYG中的细胞没有明显的适应期;转入L-15-PG中的细胞需1个月左右才能正常传代;转入L-15-G中的细胞需45~60d才能正常传代。L-15-LYG替代TNM-FH对4种昆虫细胞的形态、大小、最大生长密度和群体培增时间没有显著影响,对芹菜夜蛾核型多角体病毒AfaMNPV胞外病毒粒子的滴度没有明显的变化,但多角体的产量显著下降。     

MB和CMC液体培养基对禾谷镰孢产孢水平的影响

禾谷镰孢分生孢子定量接种是研究作物抗禾谷镰孢的必要手段?本试验利用绿豆(mung bean, MB)与羧甲基纤维素(carboxylmethyl cellulose, CMC)液体培养基在相同条件下培养禾谷镰孢, 比较两种培养基对禾谷镰孢产孢效率的影响; 并用两种培养基诱导分生孢子制成相同浓度孢子悬浮液, 对75个玉米家系进行人工接种鉴定, 检测不同培养基所产分生孢子致病性差异?结果表明, CMC培养基诱导分生孢子增长率(k2=1.125)大于MB培养基诱导增长率(k1=0.844)?在培养第14天, MB培养基诱导获得的分生孢子平均浓度为2.51×105个/mL, CMC培养基诱导的为3.62×105个/mL, 比MB培养基诱导多44.22%?用两种培养基诱生的孢子进行田间接种, 玉米穗腐病发病程度无明显差异?CMC培养基具有产孢快?孢子浓度高的优点, 是一种适宜禾谷镰孢分生孢子诱生的高效液体培养基?     

紫花苜蓿下胚轴愈伤组织诱导及再生植株的研究

以培养4～5d的紫花苜蓿无菌苗的下胚轴为材料,改良SH(SH大量元素+MS微量元素+MS铁盐+UM有机)+水解酪蛋白(CH)2000 mg/L为基本培养基,对紫花苜蓿愈伤组织诱导和植株再生进行了研究。愈伤组织诱导和继代培养基分别为2,4-D 1.0 mg/L+KT 0.5 mg/L+蔗糖30 g/L及2,4-D 0.05 mg/L+BA0.5 mg/L+蔗糖30 g/L,将获得的愈伤组织转入正交设计的培养基上进行筛选,得到了愈伤组织分化率相对较高的培养基配方:基本培养基+KT 0.4 mg/L+蔗糖20 g/L,其分化率为73.0%。获得的再生芽在生根培养基上(1/2MSO)培养约10d便能获得具有根和叶的再生植株。本试验结果为下一步将来自蓝藻的Na⁺/H⁺ an-tiporter基因转入苜蓿,获得转基因耐盐苜蓿奠定了基础。     

Testing a Rapid Diagnostic Medium for Erwinia amylovora and Development of a Procedure for Sampling Blossoms in Pear Orchards

ABSTRACT The coliform agar produced by Merck was tested for rapid diagnosis of Erwinia amylovora (the causal agent of fire blight) in pear blossoms. The medium enabled the diagnosis to be completed within 36 h. Diagnoses performed with the medium were confirmed by the BIOLOG and the fatty-acid profile methods. The diagnostic medium was used to determine the spatial distribution of colonized blossoms in the orchards and it was found that E. amylovora may be distributed both in clusters and at random. These findings were used in the development of a statistical model for sampling blossoms in the orchard. The model determines the number of trees to be sampled in the orchard and the number of blossoms be taken from each tree, which would enable the true colonization incidence of blossoms in the orchard to be estimated at desired levels of accuracy and confidence. Parameters included in the model are: the total number of trees in the orchard (T), the number of trees to be sampled in the orchard (t), the number of blossoms to be sampled from each tree (n), the true colonization incidence of blossoms (pi), a coefficient of aggregation (rho), the required level of confidence (1 - alpha), and the required level of accuracy (L). Sensitivity analyses revealed that the parameter governing sample size is the required level of accuracy. Sampling of 20 blossoms from each of several hundred trees is required to achieve an accuracy of +/-1%, but only a few single trees are needed for an accuracy level of +/-10%. A sampling procedure then was developed, validated with an independent data set, and found to be accurate. It was concluded that sampling of pear blossoms and estimation of the incidence of blossom colonization by E. amylovora could improve fire blight management, but not in all cases.     

Development of a semi-selective medium for isolation of <Emphasis Type="Italic">Xanthomonas campestris</Emphasis> pv<Emphasis Type="Italic">. musacearum</Emphasis> from banana plants

Banana Xanthomonas wilt, caused by Xanthomonas campestris pv. musacearum, is a new threat to banana cultivation in eastern Africa. The causal bacterium grows slowly in culture and is easily overgrown by contaminants. A selective culture medium for isolation of X. c. pv. musacearum will facilitate disease study. A medium that suppressed saprophytic growth and possessed diagnostic characters for the pathogen was developed. Various carbon sources were tested with two isolates of X. c. pv. musacearum, and sucrose was selected as main carbon source. The susceptibility of X. c. pv. musacearum and other bacterial strains was tested with 29 different antibiotics. Cephalexin and cycloheximide had no effect on X. c. pv. musacearum but cephalexin inhibited most of the saprophytes and cycloheximide inhibited the fungal contaminants. Based on these studies, we have developed a semi-selective medium YTSA-CC containing yeast extract (1%), tryptone (1%), sucrose (1%), agar (1.5%), cephalexin (50 mg l⁻¹) and cycloheximide (150 mg l⁻¹), pH 7.0. The pathogen X. c. pv. musacearum was easily identified as yellowish, mucoid and circular colonies on YTSA-CC medium. This simple semi-selective medium was effective for isolation of X. c. pv. musacearum from infected banana tissues and soil, and it should be a valuable tool in ecological and epidemiological studies.     

Comparison of PCR, BIO-PCR, DIA, ELISA and isolation on semiselective medium for detection of Xanthomonas albilineans, the causal agent of leaf scald of sugarcane

Polymerase chain reaction (PCR) and newly designed primers, XAF1/XAR1, were tested for selective detection of the causal agent of leaf scald of sugarcane, Xanthomonas albilineans . The efficiency and reliability of PCR were compared with dot immunobinding assay (DIA), ELISA and classical isolation techniques for detecting X. albilineans in suspensions of pure cells and extracts of field-collected stalk and leaf samples of sugarcane. In addition, classical PCR and BIO-PCR (biological amplification followed by PCR) were compared with isolation on a semiselective agar medium. Classical PCR and BIO-PCR techniques had the advantage of not requiring pathogenicity tests to confirm the identity of colonies tentatively identified as X. albilineans on modified semiselective XAM agar medium. The m-XAM medium and BIO-PCR techniques were the most sensitive; however, the former required seven days whereas the latter required only four days. The BIO-PCR technique was as sensitive as the semiselective medium technique and eliminated the need to conduct any additional tests to confirm the identification.     

Improved Medium for Selecting Nitrate-Nonutilizing (nit) Mutants of Verticillium dahliae

ABSTRACT Nitrate-nonutilizing (nit) mutants are commonly used to determine vegetative compatibility between isolates of Verticillium dahliae by complementation (heterokaryon) testing. These mutants emerge spontaneously as chlorate-resistant sectors growing out of partially restricted, wild-type colonies on chlorate-amended media. The commonly used chlorate media are based on minimal medium (MMC) or cornmeal agar (CMC), amended with potassium chlorate. nit mutants recovered on these media constituted 10 to 36%(on MMC) and 25 to 45%(on CMC) of the apparently resistant sectors. An improved water agar chlorate medium (WAC) is described that is more effective for selecting chlorate-resistant nit mutants. WAC medium consists of agar (2%), glucose (0.02%), and potassium chlorate (2 to 5%). On WAC, growth of most V. dahliae isolates was strongly inhibited, and 66 to 100%(average >80%) of the chlorate-resistant sectors formed were nit mutants. Most mutants were characterized as nit1, and about 6% as NitM.     

Effects of agrochemical residues on four spider taxa: Laboratory methods for pesticide tests with web-building spiders

The susceptibility of web-building and hunting spiders from the tropics (Panama), Europe (F.R. of Germany) and the Middle East (Israel) to 30 pesticides (16 insecticides, 4 acaricides, 1 herbicide, 9 fungicides) was determined. Laboratory test methods for juvenile and adult web-building spiders are described.Philodromus sp. (hunting spider), was completely resistant to all substances;Argiope sp. (web-building spider),Linyphia sp. (web-building spider) andChiracanthium sp. (hunting spider) showed medium to high susceptibility. Insecticides affected spiders in a wide range of responses: from no mortality (most compounds of biological origin) and medium mortality (pyrethrin compounds, organophosphorus and carbamate compounds), to high mortality (cyclo compounds). To both groups of spiders (the hunting and web-building), most acaricides were highly toxic, whereas herbicides and fungicides were nontoxic.     

小麦矮腥黑穗病在中国定殖风险分析及区划研究

 本研究根据小麦矮腥黑穗病菌Tilletia controversa Kühn (TCK)萌发侵染的条件,结合气象数据,利用地理信息系统分析了TCK在中国冬麦区的定殖可能性。根据18年内出现适合TCK发生的年数,将中国冬麦区划分为4类,即高、中、低风险区和基本不发生区。18年内可能发生9年以上的地区为高风险区,可能发生4~8年的地区为中风险区,可能发生1~3年的地区为低风险区。计算出各风险区所占冬麦区的面积,其中,高中风险区约占全国冬麦区总面积的19.3%。