枸杞红瘿蚊和枸杞白瘿蚊所致虫瘿形态结构差异

枸杞红瘿蚊是宁夏枸杞上重要成灾害虫之一。枸杞白瘿蚊是继枸杞红瘿蚊后在宁夏枸杞上新发现的另一种瘿蚊科害虫。两种瘿蚊均以幼虫为害宁夏枸杞幼嫩花蕾使其不能正常发育,但形成的虫瘿结构差异明显。本文通过外部形态观察、石蜡切片等方法对两种虫瘿发育过程中的外部形态特征、内部组织结构进行了对比。结果表明,两种瘿蚊幼虫的取食不会引起花部结构的增加或缺失,但均影响花部结构发育,使其无法正常开花结果。枸杞红瘿蚊主要造成子房细胞数量增多形成虫瘿,枸杞白瘿蚊主要造成花冠细胞体积增大形成虫瘿。此外两种虫瘿在花柱、花丝、蜜腺、花药、花柄等处均存在一定差异。     

Feasibility of biological control of the sugarcane scale insect Melanaspis gfomerata in India

Abstract

Melanaspis glomerate (Green) is a serious pest of sugarcane in India and does not have effective natural enemies. Parasites of M. smilacis Comst. and M. paulislus Hempel from Brazil and Aphytis mytilaspidis (Le Baron) collected from Aulacaspis tegalensis (Zehnt.) in Mauritius were imported for biological control trials. Only Neococcidencyrtus sp., an endoparasite of M. paulistus accepted M. glomerata. Among the coccinellid predators that were imported only Chilocorus cacti (L.) bred on M. glomerata. The non‐acceptance of this scale insect by most of the introduced natural enemies seems to indicate the need for confirmatory studies on its taxonomic status. Until such time as this is done and suitable natural enemies are found, an integrated approach for its control may have to be considered.     

水稻品种抗稻瘿蚊与主要农艺性状的关系

对水稻品种抗稻瘿蚊与主要农艺性状关系的研究结果表明,水稻品种抗稻瘿蚊与其分蘖力、始穗期、抽穗期、齐穗期、生育期、株高、有效穗、穗粒数、结实率、千粒重的相关均不显著。水稻品种抗稻瘿蚊与其主要农艺性状并无矛盾,在抗稻瘿蚊育种中可以选育出高产且抗性强的品种。     

小麦品种抗吸浆虫鉴定

１９９１～１９９４年利用一套较完整的田间抗性鉴定方法，对４４３个生产品种、后备品种及抗源进行了抗吸浆虫鉴定。结果表明，参试品种（系）对吸浆虫的抗性差异显著。高抗、中抗和低抗的品种（系）分别占参试材料的１３．１％、１２．９％和２８．１％，其中冀麦２３、２４和２５号、遗４１７９、４１５４、４１８８、郑太育一号等１８个品种（系）对吸浆虫连续几年表现出稳定的抗性。鉴定结果为生产和育种部门利用抗虫品种提供了科学依据。     

国际水稻遗传评价试验网材料对稻褐飞虱和稻瘿蚊的抗性鉴定

对引进的国际水稻遗传评价试验网的材料进行抗稻褐飞虱和稻瘿蚊的抗虫性鉴定,筛选出一批抗稻褐飞虱和稻瘿蚊的品种(材料),其中高抗稻褐飞虱的有IR3383-9-1-13、IR40931-43-2-2-3-2、IR39334-31-2-2-2;高抗稻瘿蚊的有KANGWEN2、ARC5833、DUOKANGI1、ARC5984、RP2572-18-316、RP2337-253-65-11、PHALGUNA、ARC5987。这些材料可供抗稻飞虱和稻瘿蚊育种选用。     

我国河南和甘肃地区梨树根癌病病原菌鉴定

近年来, 我国梨树根癌病多有发生, 危害严重, 但病原尚不明确?本研究采集了河南商丘和甘肃庆阳梨树根瘤, 共分离得到13个分离物, 对其进行形态特征观察?序列分析和特异性PCR检测?生理生化测定和致病性测定?结果表明, 这13个分离物在NA平板上的菌落呈白色?圆形, 单菌落中间凸起?边缘整齐?它们均能在New Kerr培养基上良好生长?其16S rRNA基因序列与GenBank中已登录的Agrobacterium tumefaciens和A.rhizogenes序列相似性大于98%?将分离物人工接种向日葵后能使接种部位产生癌瘤?鉴定结果表明, 梨树根瘤中分离出的13个分离物均为生物Ⅱ型土壤杆菌?     

一种危害杧果幼果的瘿蚊科害虫

杧幼果普瘿蚊(Procontarinia frugivora Gagné)是目前已知唯一危害杧果果实的地区性害虫,国内尚未发生分布。本文综述了其分类地位、地理分布、成虫形态特征、生物学特性、传播途径等,讨论了其经济重要性及防治对策,提出了进境检疫鉴定方法,以期为进境检疫工作提供参考。     

水稻瘤矮病毒广东分离物基因组第10组分的序列分析及原核表达

 应用RT-PCR技术克隆了水稻瘤矮病毒(Rice gall dwarf virus,RGDV)广东分离物基因组的第10片段,并测定了全序列。结果表明,RGDV广东分离物S10(登录号EF532325)全长1198bp,含有一个ORF,编码一条由320氨基酸组成、推测分子量约36kDa的多肽。与泰国分离物相应组分相比,基因结构基本一致,核苷酸和氨基酸序列同源性分别为96.2%和98.8%;S10编码多肽与水稻矮缩病毒(Rice dwarf virus,RDV)s9编码蛋白及伤瘤病毒(Wound tumor virus,WTV)S11编码蛋白也分别具有29%和33%的相似性。本研究还将S10cDNA克隆至原核表达载体pET28b(+)上,通过IPTG诱导在大肠杆菌BL21(DE3)中得到了高效表达,并利用His,Bind树脂纯化得到电泳纯级制品。本工作为进一步研究S10编码蛋白的结构与功能奠定了一定的基础。     

两种五倍子蚜虫的鉴定及倍子形态与倍蚜数量关系研究

通过观察由张家界市所产的蛋铁倍和角倍内致瘿蚜虫的玻片标本,确定了两种蚜虫分别为肚倍蚜蛋铁亚种Kaburagia rhusicola ovogallis（Tsai et Tang）和角倍蚜Schlechtendalia chinensis（Bell）。分析了角倍干湿重与倍子内蚜虫的数量关系,角倍体积与蚜虫的数量关系,初步得出结果显示：倍子内蚜虫的数量并不随五倍子的重量和体积的增大而增加。     

水稻瘤矮病毒S11基因沉默抑制子的原核表达及抗血清制备

以采自广东省水稻瘤矮病的典型病株为材料,通过RT-PCR法扩增和克隆了水稻瘤矮病毒(Rice gall dwarf virus,RGDV)S11组分核苷酸序列全长。序列分析结果表明,RGDV广东分离物S11(登录号EF532326)核苷酸序列全长1168bp,含有一个1068bp的开放阅读框,编码一条355个氨基酸的多肽,推测分子量约40kD,与泰国分离物基因结构基本一致,其核苷酸与氨基酸序列相似性分别为94.3%和98.8%。将广东分离物S11基因克隆至pBV221温敏表达载体上,在大肠杆菌DH5α中实现了高效表达。以诱导蛋白为抗原免疫家兔获得了抗血清。利用ELISA法测定抗血清的效价为1∶4096,Western blot分析结果表明,抗血清能与S11蛋白发生特异血清学反应。这可为进一步研究S11蛋白的结构和功能,揭示其抑制基因沉默的作用机制提供参考。     

小麦品种(系)抗麦红吸浆虫鉴定及利用

2004-2006年利用一套较完整的田间抗性鉴定方法,对425份生产推广品种(审定品种)、区试品种及品种资源进行了抗麦红吸浆虫鉴定。结果表明,不同小麦品种(系)对麦红吸浆虫的抗性差异显著,高抗品种(系)有56份,占供鉴品种的13.18%、中抗品种54份,占12.71%、低抗品种99份,占23.29%。在近年已审定品种中,石7221、良星99、1457、衡71-3、中麦9、石新822、石家庄11号等7个小麦品种对麦红吸浆虫均表现出稳定的抗性。     

不同水稻品种对二化螟的抗性及其与形态学和解剖学特征的关系

在实验室条件下研究了6个不同类型的水稻品种对二化螟的抗性及其与形态学和解剖学特征的关系。结果表明，二化螟幼虫在粳稻品种辽粳294和秀水11上的存活率最低，显著地低于在超级杂交籼稻两优培九和杂交籼稻汕优63上的存活率，但超级杂交籼稻协优9308和杂交籼稻汕优10上的存活率无显著差异。60日龄时汕优63的分蘖数最多，汕优10次之，辽粳294最少。杂交水稻品种的株高显著高于普通粳稻品种，而辽粳294和汕优63的叶鞘显著短于其它品种。除协优9308与两个粳稻品种无显著差异外，其它三个杂交稻品种的叶宽和叶角均大于粳稻品种。60日龄时杂交籼稻品种两优培九叶鞘的维管束间距最宽，辽粳294的维管束间距最窄，但其维管束直径最大。辽粳294和秀水11叶鞘硅细胞的密度显著高于其它几个籼稻品种。被二化螟幼虫危害后，除汕优10叶鞘的维管束间距略有下降（-0．28％）外，其它几个品种的叶鞘维管束间距均增大，其中辽粳294增幅最大，为33．33％。而维管束直径和硅细胞密度均有不同程度的下降，其中硅细胞数下降最为明显。     

泰安樱桃根癌病致病菌分离及生物型鉴定

由致病性土壤杆菌侵染引起的根癌病严重影响了樱桃树的生长?利用选择性培养基, 以阿糖醇和赤藓糖醇作为不同碳源, 从山东泰安食用樱桃根部瘤状组织和感病根际土壤中分离到土壤杆菌100余株, 通过胡萝卜切片法和番茄茎部针刺接种法从中筛选到31株有致瘤活性的菌株?经16S rDNA和recA基因序列分析, 结合生物型检测鉴定出96%以上的致病菌属原生物Ⅱ型(Agrobacterium rhizogenes), 只有1株致病菌为原生物Ⅰ型(A. tumefaciens)?根据Ti质粒上致病相关基因保守序列设计3对引物, 12株有致瘤活性菌株中11株PCR扩增到目的条带?经分子生物学测定和高压纸电泳检测, 所有致病菌株的质粒均为胭脂碱型?建立了致病型土壤杆菌的分子生物学快速鉴定方法, 为定向选择生防菌株提供基础?     

Arthropod populations and rice yields in direct-seeded and transplanted lowland rice in West Africa

Studies were conducted on the effect of pruning time, host age, urediniospore release and weather parameters on the incidence and intensity of mulberry leaf rust (Peridiopsora mori). Rust severity significantly increased with increasing shoot age, irrespective of pruning time. Maximum disease severity was observed in plants pruned during the third week of October, and minimum severity in plants pruned during last week of November. Apparent infection rate was higher in younger shoots. Infection rate was higher in plants pruned during the last week of November. Urediniospore release was influenced by prevailing climatic conditions. A higher rate of spore release was noticed during sunny days. Maximum spore release was found between 12.00 h and 14.00 h. Spore release was positively correlated with temperature and negatively correlated with relative humidity. Rust severity (34.97%) was higher in January and least (1.03%) during May. Rust severity was negatively correlated with both temperature and rainfall. An exponential model was developed for the prediction of rust severity which was accurate up to 96.60%.     

水稻瘤矮病毒P12蛋白抗血清制备及其应用

为了进一步研究水稻瘤矮病毒(Rice gall dwarf virus,RGDV)P12的功能,将RGDV-GX P12编码区亚克隆至原核表达载体,并导入大肠杆菌诱导表达;重组的P12融合蛋白经Ni-NTA His·Bind Resins纯化后用于免疫小鼠制备抗血清,并进行Western blotting分析。结果显示,约41 kD大小的RGDV P12融合蛋白可在大肠杆菌中高效表达;利用该重组蛋白所制备的抗血清可特异地与融合表达和非融合的P12蛋白发生强烈的免疫学反应。利用该特异性抗血清在病毒粒子样品中检测不到P12蛋白,而在病株总蛋白样品中可检测到1条与预期大小一致的明显条带,表明RGDV P12是一种非结构蛋白。     

不同番茄品种对5种植物双生病毒的抗病性鉴定

 由粉虱传双生病毒引起的番茄曲叶病［1］在我国最初仅分布在海南、云南、广东和广西,自2006年上海市和浙江省先后在番茄上发现番茄黄化曲叶病毒（Tomato yellow leaf curl virus,TYLCV）以来,该病害蔓延迅速,在多个省份的番茄上暴发成灾［2］。引起番茄曲叶病害的病原较复杂,在我国其主要病原为TYLCV、中国番木瓜曲叶病毒（Papaya leaf curl China virus, PaLCuCNV）、中国番茄黄化曲叶病毒(Tomato yellow leaf curl China virus, TYLCCNV)、泰国番茄黄化曲叶病毒（Tomato yellow leaf curl Thailand virus, TYLCTHV）和台湾番茄曲叶病毒（Tomato leaf curl Taiwan virus, ToLCTWV）［2~5］,而浙江省的主要病原为TYLCV和ToLCTWV。选育抗病品种是防治番茄黄化曲叶病最有效的手段。了解番茄品种对不同双生病毒的抗性,对因地制宜布局抗病品种具有重要意义。浙杂502、浙粉701、浙粉702是浙江省大规模种植的番茄品种,为了解这些品种对上述5种病毒的抗性,本研究利用5种病毒的侵染性克隆,在人工接种条件下,综合评定分析这3个番茄品种的抗病指标。     

Estimation of rice yield losses due to the African rice gall midge,Orseolia oryzivora Harris and Gagne

Abstract

The African rice gall midge, Orseolia oryzivora Harris and Gagne (Diptera: Cecidomyiidae), is an important pest of rice, Oryza sativa, in Burkina Faso as well as other countries in West and East Africa. In spite of its importance, little is known regarding the relationship between gall midge populations and grain yield losses. To determine yield losses the gall midge was reared in cages and adult midges were placed on caged plants of the rice variety ITA 123 at different population levels. The seven treatments consisted of different numbers of insects infested on the plants; 0 insect pairs (non‐infested check), and 1, 5, 10, 15, 20 or 25 midge pairs/cage. The loss in yield in relation to the non‐infested control was highly positively correlated (R² = 0.81) with the percentage of gall midge damaged tillers. The infestation by the insect on the plants resulted in the compensatory production of tillers which developed in response to the gall midge damage but the compensation was not sufficient to make up for the loss of yield due to the damaged tillers. Yield loss ranged from 0% in the control to 65.3% in the treatment with 25 pairs of adults. One per cent of tillers damaged resulted in 2% grain yield loss.     

Identification of a bacterium isolated from galls on carrot and weeds

In 2004, bacterial galls were found on the roots of carrots in Shizuoka Prefecture, Japan. Galls were about 0.1–2 cm in diameter, light brown in color and had rough surfaces. In 2005, similar galls were found on the roots of three weeds: henbit (Lamium amplexicaule L.), Persian speedwell (Veronica persica Poir.) and leaf mustard (Brassica juncea L.). A bacterium that forms white, rough colonies was isolated from the carrot and weeds galls. The bacterial isolates had properties identical with Rhizobacter dauci Goto and Kuwata. Phylogenetic analysis based on 16S rDNA sequences showed that the carrot isolate had the highest homology (similarity of 100%) with that of the type strain of R. dauci. Rep-PCR genomic fingerprinting using BOX A1R primer showed that the carrot and weeds isolates were nearly identical. Pathogenicity of the isolates was confirmed by inoculating the roots of carrots and the weeds. After 2–5 weeks, they formed galls on the roots of the original host species and on other plant species tested. The galls were indistinguishable from those formed naturally, and the inoculated bacterium was reisolated. Thus, the causal bacterium of carrot and weeds gall was identified as R. dauci, and the bacterium was found to have a wider host range than previously known. These weed hosts may serve as inoculum sources for carrot bacterial gall disease.     

In vitro but not in planta encapsidation of Rice gall dwarf virus core particles by the outer capsid P8 protein of Rice dwarf virus expressed in transgenic rice plants

Transencapsidation of the Rice gall dwarf virus (RGDV) inner core by the Rice dwarf virus (RDV) outer capsid P8 protein was examined in vitro and in planta. When RGDV core particles were incubated with an extract from RDV P8-transgenic rice leaf tissue, RDV P8 encapsidated the RGDV core particles to form double-shelled virus-like particles in vitro. In contrast, when RDV P8-transgenic rice plants were inoculated with RGDV, progeny RGDV particles contained RGDV P8 but RDV P8 was not detectable in the virions. No significant differences were found in acquisition by the vector insects and subsequent transmission rates between RGDV infecting nontransgenic rice plants and those infecting RDV P8-transgenic rice plants. These results indicate that mechanisms of and/or requirements for interactions between P8 and the inner core particles of phytoreoviruses differ between in vitro and in planta.