Brugia malayi in Mastomys natalensis: efficacy of mebendazole in combination with Freund's complete adjuvant.

The chemotherapeutic efficacy of mebendazole given in combination with Freund's complete adjuvant (FCA) against Brugia malayi in multimammate rat was evaluated. Animals treated with mebendazole, orally at 200 mg/kg x 5 consecutive days along with FCA given subcutaneously (s.c.) on day -10, day 0 and day +15 of the drug treatment killed 48.51% of the adult worms. This drug given alone at the same regimen and by the same route showed only 18.7% mortality rate on adults. Mebendazole given intraperitoneally along with FCA given s.c., however, was four times more efficacious as filaricide than mebendazole alone. Nevertheless, the animals receiving FCA alone also revealed 23.5% mortality rate of adult worms. The animals receiving a combination therapy or FCA alone showed significant increase in antibody titre to the filariae which however decreased in the later stages. No enhancement of antibody level could be detected in animals treated with mebendazole alone. The non-specific immunopotentiation induced by FCA appeared to play a major role in enhancing the activity of mebendazole.     

Stage-specific antibody response of Mastomys natalensis during the course of Dipetalonema viteae infection

Stage-specific haemagglutinating (HA) and precipitin antibodies (PA) to infective larvae (L3), adult worms and microfilariae (mf) have been demonstrated in sera of Mastomys natalensis during the course of Dipetalonema viteae infection using indirect haemagglutination (IHA) and Ouchterlony's gel-diffusion tests. L3-specific HA antibody titre was shown to be quite low and lasted for shorter period whereas adult-specific antibody response was significantly higher and persisted for longer duration (beyond day 240 post exposure). No precipitin antibody to L3 stage could be detected, however, significant adult-specific antibody was detected which ultimately tapered off by day 210 post exposure (p.e.). In contrast, mf-specific PA which appeared at the beginning of patency, never disappeared even at the late stage of infection. Mf-specific HA antibody appeared at early incubation period (day 15 p.e.) and after exhibiting two peaks, one in the midst of prepatent period (day 30 p.e.) and the other on day 180 p.e. persisted at low level during the late stage of infection when amicrofilaraemia developed.     

Brugia malayi: status of host during different stages of infection

The status of glycogen, protein, lipid components, lipid peroxides and a few enzymes of energy metabolism was studied in liver of Mastomys natalensis during the development of Brugia malayi infection. Glycogen and lipid contents were decreased during the patent phase of infection while total protein was slightly altered in latent animals. Phospholipid and triglyceride contents declined at prepatent and patent phase of infection. The levels of lactate and malate dehydrogenases, as well as of adenosine triphosphatases (Na+K+, Mg2+, Ca2+), were significantly elevated and monoamine oxidase activity was decreased at patent phase of infection, while succinic dehydrogenase remained unaltered. The lipid peroxide formation was enhanced in liver during the development of filarial infection.     

Food preferences of the multi-mammate mouse,Mastomys natalensis,in irrigated rice habitats in Tanzania

We investigated the composition of the diet of the multi-mammate mouse, Mastomys natalensis, within irrigated rice and fallow field habitats at set time periods related to rice crop growth stages. In both habitats, vegetative plant material, i.e. leaves, stems and seeds, were the most abundant components of the rodent's diet, while other food types (invertebrates, fruits) were observed only in low quantities. We conclude that vegetative plant material and seeds were the main types of food consumed not only due to their relatively higher abundance in the environments under study but also because of the highly specialised herbivorous/granivorous nature of the dominant rodent species, M. natalensis. Thus, the introduction and expansion of continuous rice-cropping using irrigation in Tanzania is likely to be severely constrained by the presence of M. natalensis. In our opinion, field hygiene, including the removal of alternative food resources and nesting sites for M. natalensis near cropping areas, may help to both lower rodent population numbers and reduce immigration potential. Non-chemical rodent control methods such as trap barrier systems developed for lowland irrigated rice in south-eastern Asia should, we argue, be evaluated for their effectiveness under African conditions.     

二化螟对不同药剂的敏感度研究

为了解江西省不同地区二化螟对不同类型杀虫剂的敏感度水平,科学指导二化螟的田间药剂防治,应用点滴法测定了江西省代表性稻区二化螟对5大类8种杀虫剂的敏感度。结果表明,靖安、南昌、吉安稻区二化螟对三唑磷、毒死蜱、稻丰散和杀虫单敏感度极低,对丁烯氟虫腈和氯虫苯甲酰胺敏感度较高,对甲维盐和阿维菌素敏感度最高;3个稻区的二化螟种群对试验药剂的敏感度,除毒死蜱和阿维菌素外（相对敏感性指数为3.88、3.85）,对其他药剂的敏感度差异不大（相对敏感性指数均低于1.5）。     

Susceptibility of spring wheat to infestation with wheat blossom midges and thrips

Journal of Plant Diseases and Protection - Susceptibility of spring wheat to infestation with wheat blossom midges (WBM) and thrips was studied in Central Germany in the two seasons, 2008 and 2009....     

116株芒果炭疽病菌对咪鲜胺的敏感性测定

研究芒果炭疽病菌对咪鲜胺的敏感性, 以期为该病的综合防治提供参考。从国内及国外芒果产区采集病样, 分离、纯化芒果炭疽菌菌株, 采用生长速率法测定芒果炭疽病菌对咪鲜胺的敏感性。结果表明, 分离获得的116株芒果炭疽病菌菌株对咪鲜胺的EC50值为0.000 8～0.073 9 μg/mL, 平均值为0.012 4 μg/mL, EC50最大值是最小值的92.4倍。不同采集地区和采集部位菌株对咪鲜胺的敏感性不同, 美国夏威夷的菌株敏感性最低, 广东的最高; 分离自叶片的菌株敏感性最高, 果实的最低。芒果炭疽病菌对咪鲜胺具有较高的敏感性, 生产上仍具有较高的使用价值, 但不同菌株的敏感性之间具有一定差异性, 存在潜在的抗性风险。     

Susceptibility of seven annual grasses to herbicides

The relative susceptibility of Digitaria sanguinalis (L.) Scop, (large crabgrass), Echinochloa crus-galli (L.) Beauv. (barn-yardgrass), Eriochloa villosa (Thumb.) Kunth. (hairy cup-grass), Setaria faberi Herrm. (giant foxtail), Setaria lutescens (Weigel) Hubb. (yellow foxtail), Setaria viridis (L.) Beauv. (green foxtail) and Setaria viridis var. robusta-purpurea Schreiber (robust-purple foxtail) to alachlor, atrazine, butylate and cyanazine was studied under glasshouse conditions. Hairy cupgrass was the least susceptible to the herbicides tested, of which alachlor appeared to be the most effective. Large crabgrass was controlled by alachlor, butylate and cyanazine at all of the rates tested, but by atrazine only at rates above 0–56 kg/ha. All four herbicides provided acceptable control for barnyardgrass, giant foxtail, green foxtail, robust-purple foxtail, and yellow foxtail. The susceptibility of the grasses to cyanazine and alachlor was correlated with seed size. Alachlor was more effective in controlling green foxtail and hairy cupgrass when applied to the soil surface before emergence than when incorporated into the soil prior to sowing. Sensibility de sept graminées annuelles à divers herbicides La sensibilité relative des espéces suivantes: Eriochloa villosa (Thumb,) Kunth. Echinochloa crus-galli (L.) Beauv. (panic). Digitaria sanguinalis (L.) Scop, (digitaire), Setaria faberi Herrm, (sétaire). Setaria viridis (L.) Beauv., Seiaria viridis var. robusla-purpurea Schreiber ct Seiaria lutescens (Weigel) Hubb., (sétaires) a étéétudiéé en serre. vis-d-vis de I'atrazine. de la cyanazine, du butylate et de I'alachlore. Eriochloa villosa a été I'espéce la moins sensible aux herbicides essayds parmi lesquels I'alachlore s'est montré le plus efficace. La digitaire a été maitrisé par I'alachlore, le butylate et la cyanazine k toutes les doses essayees, mais pour I'atra-zine. seulement à des doses supérieures à 0.56 kg/ha. Ces quater herbicides ont donne des resultats acceptables contre le panic, et les sétaires (S. faberi, S. viridis, S. viridis var. robusta-purpurea, S. lutescens). La sensibilité des graminées à la cyanazine et à I'alachlore fut en corrélation avec la taille des semences. L'alachtore s'est montré plus efficace contre la sétaire S. viridis var. robusta-purpurea ct contre l'Eriochloa villosa quand il a été appliqué sur la surface du sol avant la levée que lorsqu'il a éié incorporé au sol avant le semis. Die Empfindlichkeit von sieben einjährigen Gräsern gegenüber Herbiziden. Es wurde die relative Empfindlichkeit von Digitaria sanguinalis (L.) Scop., Echinochloa erus-galli (L.) Beauv., Eriochloa villosa (Thumb.) Kunth-, Setaria faberi Herrm., Setaria lutescens (Weigel) Hubb., Setaria viridis (L.) Beauv. und Setaria viridis var. robusta-purpurea Schreiber gegenuber Atrazin, Cyanazin, Butylat und Alachlor unter Gewächs-hausbedingungen untersucht. Eriochloa him war gegenúber den gepruften Herbiziden am wenigsten empfindlich, Alachlor scliien die beste Wirkung zu haben. Digiiaria sanguinalis wurde durch Alachkir. Butylat und Cyanazin bei alien gepruften Aiifwandmengen bekampft, durch Atrazin aber nur bei Aufwandmengen ilber 0.56 kg/ha. Alte vier Herbizide ergaben eine brauchbare Bekampfung von Echinochloa crus-galli, Seiaria Jabcri, Seiaria viridis. Setaria viridis var. robusta-purpurea und Setaria luiescens. Die Emptindlichkeit der Gräser gegenüber Cyanazin und Alachlor stand in Beziehung zur Samengrösse. Alachlor bekämpfte Seiaria viridis und Erioehloa villosa im Vor-auflaufverfahren besser als im Vorsaatverfahren mit Ein-arbeitung.     

116株芒果炭疽病菌对咪鲜胺的敏感性测定

研究芒果炭疽病菌对咪鲜胺的敏感性,以期为该病的综合防治提供参考。从国内及国外芒果产区采集病样,分离、纯化芒果炭疽菌菌株,采用生长速率法测定芒果炭疽病菌对咪鲜胺的敏感性。结果表明,分离获得的116株芒果炭疽病菌菌株对咪鲜胺的EC50值为0.000 8~0.073 9μg/mL,平均值为0.012 4μg/mL,EC50最大值是最小值的92.4倍。不同采集地区和采集部位菌株对咪鲜胺的敏感性不同,美国夏威夷的菌株敏感性最低,广东的最高;分离自叶片的菌株敏感性最高,果实的最低。芒果炭疽病菌对咪鲜胺具有较高的敏感性,生产上仍具有较高的使用价值,但不同菌株的敏感性之间具有一定差异性,存在潜在的抗性风险。     

Susceptibility of cultivars of garlic to Sclerotium cepivorum

Five garlic cultivars, including one claimed to be resistant to Allium white rot, were similar in their effects on the germination of sclerotia of Sclerotium cepivorum. There was no evidence of resistance to the pathogen in any of the cultivars when tested under field conditions.     

Susceptibility in oats to stem rust induced by co-infection with leaf rust

Induction of susceptibility in oats to a normally avirulent pathotype of Puccinia graminis f.sp. avenae was studied in the presence of different pathotypes of P. coronata f.sp. avenae . Induction occurred on seedlings only in the presence of a virulent culture of P. coronata avenae and was not dependent on time or order of inoculation of either pathogen. This phenomenon was restricted to seedlings of lines possessing the Pg-a source of oat stem rust resistance. The specificity of induced susceptibility can be used as a valuable bioassay for screening and identifying Pg-a . Induced susceptibility occurred only at the seedling stage, and apparently provides no obstacle to the use of Pg-a as a source of stem rust resistance in oats.     

长期施药果园中的苹果轮纹病菌对戊唑醇和甲基硫菌灵的敏感性

为了监测果园中苹果轮纹病菌对戊唑醇和甲基硫菌灵敏感水平的变化,采用菌丝生长速率法测定了采集自山东烟台地区和北京市昌平区,有较长施药史苹果园中的苹果轮纹病菌对戊唑醇和甲基硫菌灵的敏感性。结果表明:戊唑醇对连续施用戊唑醇5年、每年施药1~2次的果园中苹果轮纹病菌的EC_(50)为0.017 4~0.114 3μg/mL,即该类果园中苹果轮纹病菌对此药的敏感性仍然保持在较高水平,与野生菌株的敏感性非常接近,没有出现敏感性分化的抗药亚群体;甲基硫菌灵对连续施用甲基硫菌灵10年、每年施药2次的果园中苹果轮纹病菌的EC_(50)为0.846 4~4.677 4μg/mL,果园中苹果轮纹病菌与野生菌株相比EC_(50)平均值约上升3.15倍,最低值和最高值分别是已报道敏感性基线的1.19倍和6.59倍,没有出现敏感性发生显著分化的抗药性亚群体。     

Susceptibility of some species of rodents to rickettsiae.

The present study was designed to test the susceptibility of free-living rodents, viz Apodemus flavicollis, Microtus arvalis, Clethrionomys glareolus, Mus musculus, and outbred white mice from Dobrá Voda farm, CSFR, to Coxiella burnetii, rickettsiae of the spotted fever group (Rickettsia sibirica, R. conorii, R. slovaca and R. akari) and rickettsiae of typhus group (R. typhi and R. prowazekii) by various routes of administration. The highest levels of antibodies to C. burnetii were found in A. flavicollis and M. arvalis inoculated intraperitoneally and intracerebrally. Antibodies to C. burnetii exerted peak levels between days 13 and 16 in contrast to white mice which showed maximum levels on day 28. When 10(0.5) and 10(0.05) EID50/0.25 ml of C. burnetii was administered intraperitoneally to A. flavicollis, M. arvalis and white mice, the agent was detected only in organs of wild animals. In addition to spleen, the bone marrow appeared as a predilective tissue for the detection of this agent. R. akari at a dose of 10(4.5) EID50/0.25 ml caused overt illness and death in rodents. Antibody levels to R. sibirica and R. conorii were dependent on dosage, route of inoculation and duration of infection, but were not dependent on animal species. Antibodies to R. slovaca and R. akari were dependent on dosage, infection duration and animal species but were not dependent on the route of infection. For R. conorii, R. sibirica and R. slovaca a sharp increase of antibody levels with high titres on days 4-6 and peak levels about day 11 post intraperitoneal infection was characteristic. Antibody level to R. akari increased up to day 21. Spotted fever group rickettsiae in rodents inoculated intraperitoneally were observed in various organs, particularly in tunica vaginalis and spleen at days 2-8 post infection. R. typhi at a dose of 10(4.3) EID50/0.25 ml inoculated intracerebrally or intraperitoneally killed white mice and inoculated intraperitoneally killed C. glareolus and M. musculus. The antibody response of white mice to intraperitoneal, subcutaneous or intranasal inoculation of this rickettsia was low and no antibody was detected following peroral administration. M. musculus did not develop antibodies after intracerebral, intranasal, subcutaneous or peroral inoculation of R. typhi. The target organs for this rickettsia were the spleen and tunica vaginalis. R. prowazekii inoculated intraperitoneally into white mice at a dose of 10(6.5) EID50/0.25 ml and at a dose of 10(4.5) EID50 into C. glareolus was fatal for these rodents.(ABSTRACT TRUNCATED AT 400 WORDS)     

不同抗性型灰葡萄孢菌Botrytis cinerea对不同作用机制杀菌剂的敏感性研究

不同类型杀菌剂对灰葡萄孢菌菌株的离体、活体毒力测定结果表明 ,苯并咪唑类的多菌灵、甲基硫菌灵之间 ,二甲酰亚胺类的腐霉利、异菌脲、菌核净之间表现交互抗性 ;苯并咪唑类和 N -苯氨基甲酸酯类乙霉威表现有负交互抗性趋势。离体测定中 ,对不同类型菌株以吡咯类杀菌剂咯菌腈 (EC50 200mg/ L) ,咯菌腈以及甾醇抑制剂戊唑醇、氟硅唑和丙环唑均表现出较高的活性。     

Susceptibility of grapevine tissues to Neofusicoccum luteum conidial infection

This study investigated the ability of Neofusicoccum luteum to infect wounded shoots, trunks, pruned cane ends, leaf surfaces, buds, berries and roots, and its further progression into stem tissues. All tissue types were susceptible to infection except roots, with highest incidences in trunks (100%), cane ends (100%), shoots (92%) and buds (88%), indicating that in New Zealand, N. luteum is primarily a trunk and shoot pathogen. In trunks, there were no external symptoms, although N. luteum could be reisolated from 60 to 70 cm acropetally from the inoculation site after 4 months, by which time the pathogen had progressed into side shoots which became necrotic. Wounded and non‐wounded buds became infected; most were killed, with basipetal progression of the pathogen into the supporting shoots. Berries wounded and inoculated at the pre‐bunch closure stage were susceptible to N. luteum infection, with isolation incidence increasing over the season and peaking at harvest, when infected berries became mummified and produced pycnidia with many conidia. The pathogen was also able to progress from berries into bunch stems and supporting canes. Results from this research have indicated that N. luteum infection can occur in all aerial grapevine tissues and progress to young stem tissues where it causes wood necrosis. Growers should remove mummified berries from vineyard trash to ensure that pruning and trimming times do not coincide with rainy periods when conidia are released and dispersed. Furthermore, the susceptibility of buds to N. luteum infection indicates the need for fungicide sprays before budburst in spring.     

Sensitivity to a Phytotoxin from Rhizoctonia solani Correlates with Sheath Blight Susceptibility in Rice

ABSTRACT Sheath blight is one of the most important and intractable diseases of rice (Oryza sativa) where limited control has been achieved using traditional approaches. Quantitative inheritance, extraneous traits, and environmental factors confound genetic analysis of host resistance. A method was developed to isolate and utilize a phytotoxin from Rhizoctonia solani to investigate the genetics of sheath blight susceptibility. Infiltration of the toxin preparation into plant leaves induced necrosis in rice, maize, and tomato. Using 17 rice cultivars known to vary in sheath blight resistance, genotypes were identified that were sensitive (tox-S) and insensitive (tox-I) to the toxin, and a correlation (r = 0.66) between toxin sensitivity and disease susceptibility was observed. Given the broad host range of R. solani, genotypes of host species may be both tox-S and tox-I. A total of 154 F(2) progeny from a cross between Cypress (tox-S) and Jasmine 85 (tox-I) segregated in a 9:7 ratio for tox-S/tox-I, indicating an epistatic interaction between two genes controls sensitivity to the toxin in rice. This work provides the means to genetically map toxin sensitivity genes and eliminate susceptible genotypes when developing sheath blight-resistant rice cultivars.     

甜菜夜蛾不同品系对甜菜夜蛾核多角体病毒的敏感性

利用寄主昆虫增殖病毒时，影响病毒产量的因素很多，其中寄主昆虫的敏感性是重要因素之一。尽管国内外在不同寄主对同种病毒敏感性方面进行了较多研究，但在相同寄主不同品系对同种病毒敏感性上的研究，尚未见报道。鉴于此，本文开展了甜菜夜蛾不同品系对甜菜夜蛾核多角体病毒（Spodoptera exigua Nucleopolyhedmvirus，SeNPV）敏感性的研究，以期筛选到高敏感性寄主昆虫，从而实现在甜菜夜蛾幼虫末龄高效增殖甜菜夜蛾核多角体病毒，达到有效提高甜菜夜蛾病毒杀虫剂生产效率的目的。现报道如下。     

Susceptibility of maize genotypes to Rhyzopertha dominica (F.)

Journal of Plant Diseases and Protection - This work examined the survival of Rhyzopertha dominica on maize kernels differing either for specific traits or for their genetic background. Maize...