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11.
Shohei MATSUURA Shigeru HOSHINO Hideaki HAYASHI Tetsuyuki KOHGUCHI Kyoji HAGIWARA Toshihiro OMURA 《Journal of General Plant Pathology》2002,68(1):99-102
DAS-ELISA proved to be reliable enough to detect a latent infection by Tomato spotted wilt virus (TSWV) in asymptomatic stock plants of chrysanthemum. A high density of Frankliniella occidentalis, the predominant vector, in the presence of latently infected stock plants resulted in a high incidence of disease in the chrysanthemum
production field. The incidence of disease was low when the vector thrips were not abundant in spite of the presence of latently
infected stock plants. These results suggest that an infestation of the vector thrips causes severe secondary spread of TSWV
originating from latently infected stock plants in chrysanthemum production fields.
Received 27 July 2001/ Accepted in revised form 27 November 2001 相似文献
12.
13.
Eiji Tanaka Chihiro Tanaka Atsushi Ishihara Yasumasa Kuwahara Mitsuya Tsuda 《Journal of General Plant Pathology》2003,69(1):1-6
Aciculosporium take (Ascomycota; Clavicipitaceae) is a causal agent of witches' broom of
bamboo plants. The symptoms of this disease are believed to be induced by plant
hormones, particularly auxins. Indole-3-acetic acid (IAA) was identified in
cultures of this fungus in an l-tryptophan-supplemented liquid medium.
IAA production was confirmed on 30 isolates of A. take from various
hosts and locations at levels up to 1 mg/l. The biosynthetic pathway of
IAA in A. take culture was examined by analyzing intermediate products
and by feeding experiments. The results showed that the indole-3-pyruvic acid
pathway (l-tryptophan → indole-3-pyruvic acid → indole
acetaldehyde → IAA) was the dominant pathway in A. take.
Received: June 3, 2002 / Accepted: July 25, 2002 相似文献
14.
Hiromitsu Furuya Tsutomu Matsumoto Shin-ichi Fuji Hideki Naito 《Journal of General Plant Pathology》2003,69(2):115-119
Rice seedling growth, estimated by plant height and root development and discoloration, was better in pasteurized soil than
in unpasteurized soil obtained from a flooded rice field. Rice seedlings also grew better in sterilized soil modified by adding
roots harvested from the pasteurized soil than in soil modified by adding roots harvested from the unpasteurized soil. The
results demonstrate that seedling growth in the rice field soil was inhibited by soil microorganisms, even though no typical
symptoms such as seedling blight or damping-off appeared. Pythium aristosporum is suggested to be involved in the inhibition. Thus, it appears that inconspicuous restraint of rice seedling growth could
occur in soils of rice paddy fields.
Received: May 20, 2002 / Accepted: October 16, 2002
Acknowledgments The authors thank Dr. T. Ichitani, former professor at Osaka Prefectural University, for providing an isolate of Pythium aristosporum for comparison, and Mr. Mitsuaki Sato of Akita Prefectural College of Agriculture for technical assistance. 相似文献
15.
Norman Owen-Smith 《Landscape Ecology》2004,19(7):761-771
Large mammalian herbivores are notorious for their propensity towards population irruptions and crashes, yet many herbivore populations remain relatively stable. I explore how resource heterogeneity within landscapes dampens population instability, using a metaphysiological modelling approach considering patch state distributions. Resource heterogeneity is functionally stabilizing through spreading consumption away from preferred resources before these become critically depleted. Lower-quality resources act as a buffer against starvation during critical periods of the seasonal cycle. Enriching resource quality is destabilizing, even if patch diversity is maintained, because food quantity then becomes the limitation. The potential consequences of landscape fragmentation are explored using the Serengeti ecosystem, characterised by broadscale resource gradients, as a hypothetical example. Further insights provided by the model are illustrated with specific examples concerning the effects of patch scales and waterpoint distribution. A metaphysiological modelling approach enables the basic consequences of landscape heterogeneity to be distinguished from further effects that may arise from specific patch scales and configurations, without the distracting detail of spatially explicit models. 相似文献
16.
Judith Hübschen Lilo Kling Ulrike Ipach Volker Zinkernagel Nathalie Bosselut Daniel Esmenjaud Derek J.F. Brown Roy Neilson 《European journal of plant pathology / European Foundation for Plant Pathology》2004,110(8):779-788
Xiphinema diversicaudatum and X. index are vector nematode species of economic importance in viticulture regions as they can transmit Arabis Mosaic, Grapevine Fanleaf and Strawberry Latent Ringspot viruses to grapevine. Wang et al. (2003) designed species-specific diagnostic primers from ribosomal genes for both these vector species as well as a vector and a non-vector species X. italiae and X. vuittenezi, respectively. Our study aimed to confirm the specificity and determine the sensitivity and reliability of the primers for the two vector species, X. diversicaudatumand X. indexwhen challenged with closely related longidorid species and general nematode communities typical of vineyard soil. With one exception, no PCR product was observed when the primers were tested against six Longidorus, one Paralongidorus and one Xiphinema non-target species. Occasionally (three out of eight replicate PCR reactions) a weak PCR product was noted when primers for X. index were tested with L. elongatus. Furthermore, when challenged with a range of non-target nematode species comprising the nematode community typical of viticulture soil, no PCR product was amplified. An experimental dilution series of extracted DNA rigorously demonstrated that DNA from an equivalent single specimen of the target virus-vector species, X. diversicaudatum and/or X. index, could be detected amongst 1000 equivalent non-targetX. vuittenezi. Also, extracted DNA from an equivalent single target specimen was detected when added to DNA extracted from the overall soil nematode community. The primers were assessed further by using serial mixtures of actual nematodes rather than extracted DNA to simulate field soil. Using this method, a single target nematode could be detected amongst 200 non-target specimens. Given their specificity, sensitivity and reliability, it appears that these diagnostic primers will be of great benefit to phytosanitary/quarantine services related to the viticulture industry. 相似文献
17.
“动物福利”这一概念的提出,标志着人们惯有的对待动物甚至对待生命的态度已经转变。“动物福利”不仅要求善待所有的生命,而且也关系到人类的公共道德和环境保护。早在19世纪初,欧洲的一些有识之士就开始了他们捍卫动物的征程。1822年世界上第一部反对虐待动物的法律在英国诞生,许多国家和地区出于对人类健康、环境保护和“动物福利”的考虑,也都相继制定了相关法律来保护动物的基本福利,禁止虐待和伤害动物。近20年来,特别是欧洲发生震惊世界的疯牛病和二恶英污染事件后,发达国家纷纷出台和制订“动物福利”法和饲料添加剂使用法来加强对动物的保护。“动物福利”国家间的差距正在成为农产品国际贸易中的新壁垒形式。 相似文献
18.
Abbas Safari Navid Ghavi Hossein-Zadeh Abdol Ahad Shadparvar Rostam Abdollahi Arpanahi 《Tropical animal health and production》2018,50(4):707-714
The aim of current study was to review breeding progress and update information on genetic strategies in Iranian buffaloes. Iranian buffalo is one of the vital domestic animals throughout north, north-west, south and south-west of Iran with measurable characteristics both in milk and meat production. The species plays an important role in rural economy of the country due to its unique characteristics such as resistance to diseases and parasites, having long productive lifespan and showing higher capability of consuming low-quality forage. In Iran, total production of milk and meat devoted to buffaloes are 293,000 and 24,700 tons, respectively. Selection activities and milk yield recording are carrying out by the central government through the Animal Breeding Centre of Iran. The main breeding activities of Iranian buffaloes included the estimation of genetic parameters and genetic trends for performance traits using different models and methods, estimation of economic values and selection criteria and analysis of population structure. Incorporating different aspects of dairy buffalo management together with improved housing, nutrition, breeding and milking, is known to produce significant improvements in buffalo production. Therefore, identifying genetic potential of Iranian buffaloes, selection of superior breeds, improving nutritional management and reproduction and developing the education and increasing the skills of practical breeders can be useful in order to enhance the performance and profitability of Iranian buffaloes. 相似文献
19.
Haemonchus contortus is a parasite of major economic importance of most sheep-rearing areas of the world. A cross-sectional study was conducted from November 2015 to March 2016 with objectives of determining the prevalence and associated risk factors of Haemonchus contortus infection in sheep slaughtered at Jimma town municipal abattoir, Ethiopia. Of the total 7000 sheep slaughtered during the study time period, 384 sheep were randomly selected and examined for parasites. The overall prevalence of Haemonchus contortus infection was 264 (68.75%). Infection rate of poor body condition animals was significantly (P?=?0.000) higher than good body conditioned animals. The mean packed cell volume (PCV) values (%) of parasitemic and aparasitemic sheep were 23.73?±?3.7 SD and 37.66?±?4.736 SD, respectively. The prevalence in adult sheep (>?1 year) was insignificantly (P?=?0.653) higher than that of young sheep (≤?1 year). The highest prevalence was recorded in sheep that originated from Seka district (73.3%) and the lowest in Kersa district (63.4%) with non-significant variation (P?=?0.691). The highest monthly mean worm burdens and prevalence of Haemonchus contortus infection were recorded in November and lowest in March. The current study revealed that Haemonchus contortus infection is an important and common parasitic disease and requires special attention to its control. 相似文献
20.
Eric Lim Teik Chung Michael Predith Frisco Nobilly Anjas Asmara Samsudin Faez Firdaus Abdullah Jesse Teck Chwen Loh 《Tropical animal health and production》2018,50(8):1727-1732
Brachiaria decumbens is an extremely productive tropical grass due to its aggressive growth habit and its adaptation to a varied range of soil types and environments. As a result of the vast availability, treated B. decumbens demonstrates as a promising local material that could be utilised as an improved diet for sheep and goats. Despite the fact that the grass significantly increases weight gains in grazing farm animals, there were many reports of general ill-thrift and sporadic outbreaks of photosensitivity in livestock due to the toxic compound of steroidal saponin found in B. decumbens. Ensiling and haymaking were found to be effective in removing toxin and undesirable compounds in the grass. Biological treatments using urea, activated charcoal, polyethylene glycol, and effective microorganisms were found to be useful in anti-nutritional factor deactivation and improving the nutritive values of feedstuffs. Besides, oral administration of phenobarbitone showed some degree of protection in sheep that fed on B. decumbens pasture. In this review, we aim to determine the effect of B. decumbens toxicity and possible treatment methods on the grass to be used as an improved diet for small ruminant. 相似文献