茭白胡麻叶斑病研究进展

综述了近年来在茭白胡麻叶斑病上的病害发生、病原菌鉴定及其生物学特性、发病规律和病害防治等方面的研究成果，论述了胡麻叶斑病的防治措施如选用抗病品种、农业防治、药剂防治、植物免疫诱导剂防治等的研究进展，总结了茭白胡麻叶斑病研究上存在的问题，并指出未来需要加强茭白胡麻叶斑病病原物种群多样性、致病力分化以及于病原菌的浸染机制及致病机理方面的研究；进一步收集、筛选与鉴定茭白抗病种质资源，培育优良的抗性品种；开展茭白胡麻叶斑病抗药性监测及抗性机理研究；筛选新型生态友好的化学农药和低毒、高效的生防菌剂。     

一类具有饱和发生率的虫媒传染病模型研究

考虑虫媒传染病具有潜伏期的特征,研究了一类具有饱和发生率的时滞传染病模型的动力学行为,确定了疾病是否流行的阈值R_0.当R_01时,无病平衡点全局渐近稳定,疾病将最终灭绝;当R_01时,唯一地方病平衡点条件稳定,系统会产生Hopf分支.     

金华市单季稻主栽品种对稻曲病的田间抗性评价

2016年采用自然诱发方法测定了金华市10个单季稻主栽品种稻曲病的发病情况,并对其抗性进行了评价。结果表明,深两优5814、甬优17、春优84、中浙优8号、甬优1540、丰两优香1号和Y两优2号对稻曲病的抗性较好,而甬优15、甬优9号、浙优18的抗性较差。     

Impact of farm management on expression of early mortality syndrome/acute hepatopancreatic necrosis disease (EMS/AHPND) on penaeid shrimp farms in Thailand

Asian shrimp farming industry has experienced massive production losses due to a disease caused by toxins of Vibrio bacteria, known as early mortality syndrome/acute hepatopancreatic necrosis disease (EMS/AHPND) for the last 5 years. The disease can cause up to 100% cumulative pond mortality within a week. The objective of this study was to identify factors associated with AHPND occurrence on shrimp farms. A case–control study was carried out on shrimp farms in four provinces of Thailand. Factors related to farm characteristics, farm management, pond and water preparation, feed management, post‐larvae (PL) shrimp and stock management were evaluated. Multivariable logistic regression analysis identified factors affecting AHPND occurrence at the pond level. Chlorine treatment, reservoir availability, use of predator fish in the water preparation, culture of multiple shrimp species in one farm and increased PL stocking density contributed to an increased risk of AHPND infection, while delayed first day of feeding, polyculture and water ageing were likely to promote outbreak protection. Additionally, the source of PL was found to be associated with AHPND occurrence in shrimp ponds, which requires further study at the hatchery level. Identification of these factors will facilitate the development of effective control strategies for AHPND on shrimp farms.     

Effects of Panax ginseng extract in practical diets for rainbow trout (Oncorhynchus mykiss) on growth performance,immune response and resistance to Yersinia ruckeri

In a preliminary in vitro study, a Panax ginseng extract exhibited an evident antibacterial activity against Yersinia ruckeri and Lactococcus garvieae and affected the respiratory burst and proliferation of rainbow trout Oncorhynchus mykiss leukocytes. Subsequently, the effects of a dietary ginseng extract supplementation on growth, blood biochemical profile, innate immune response and resistance against Y. ruckeri infection were investigated in vivo in rainbow trout juveniles. Four experimental diets were obtained by adding 0.0%, 0.01%, 0.02%, 0.03% of ginseng ethanolic extract to a commercial feed. Each diet was fed to triplicate groups of fish (mean body weight 30.5 ± 0.15 g) at 1% of body weight day^?1 for 10 weeks. The dietary supplementation with ginseng extract did not affect growth performance, feed utilization, biometric traits and fish whole body composition (P > 0.05). No major changes due to graded levels of ginseng extract in the diet were observed in blood biochemical parameters except for increasing plasma triglycerides and non‐esterified fatty acids in fish fed diets including 0.01% and 0.02% of extract (P < 0.05). The innate immune response was barely modulated by the dietary addition of ginseng extract. Serum lysozyme and leukocytes respiratory burst activities were just slightly increased in fish fed all the ginseng extract‐supplemented diets compared with controls, whereas serum antiproteases and leukocyte MPO were not affected (P > 0.05). The dietary administration of ginseng extract induced a reduction in mortality of rainbow trout infected with Y. ruckeri, although no significant differences between treated and control groups were observed (P > 0.05).     

槟榔黄化病病原及检测方法研究进展

黄化病是一种严重威胁槟榔生产种植的毁灭性传染性病害，目前主要在印度和我国槟榔主产区发生。本文从非生物与生物因素两方面对槟榔黄化病病原认识过程及检测方法进行详细的综述。     

发酵豆粕及其在水产动物生产中的应用

在日粮中使用发酵豆粕能够提高消化酶活性,增强免疫力,提高生产性能。文章就发酵豆粕的营养特性及其在水产动物生产中的应用作以简述。     

Chemical management of Fusarium wilt of watermelon

Watermelon yield loss due to Fusarium wilt is increasing in the U.S., due in part to the emergence of the virulent race 2 of Fusarium oxysporum f. sp. niveum, and to the shift in production to triploid cultivars, which generally have less host resistance than previously grown diploid cultivars. One potential management strategy is the use of soil-applied fungicides to reduce Fusarium wilt. The U.S. national program, interregional project 4 (IR-4) supported multistate trials of soil-applied chemicals to manage Fusarium wilt of watermelon. Greenhouse trials were conducted in Maryland, Indiana and Georgia to test the efficacy of 14 chemicals on Fusarium wilt. Based on the performance of these chemicals in the greenhouse, six in Maryland and Delaware and eight in Indiana were selected for subsequent field evaluations. These chemicals were applied once, as a drench at planting, in field trials in Maryland, Indiana, and Delaware in 2008. The fungicides prothioconazole, acibenzolar-S-methyl, and thiophanate-methyl resulted in the greatest reduction in Fusarium wilt, and caused no phytotoxicity. In Maryland and Indiana in 2009, these chemicals were applied through the drip irrigation line alone and in combination, at 0, 2 and 4 weeks after planting. The experiment was repeated in 2010 in Maryland. Prothioconazole alone and in combination with acibenzolar-S-methyl or/and thiophanate-methyl resulted in the greatest decrease in the area under the disease progress curve (AUDPC) of Fusarium wilt of watermelon in Maryland in 2009. The same trend was observed in 2010 in Maryland where three of the prothioconazole treatments ranked the lowest of all treatments and prothioconazole in combination with thiophanate-methyl had significantly lower Fusarium wilt AUDPC compared to the non-treated control. All chemical applications except for acibenzolar-S-methyl in combination with prothioconazole reduced Fusarium wilt AUDPC in Indiana in 2009. Prothioconazole alone and prothioconazole in combination with thiophanate-methyl ranked lowest in Fusarium wilt AUDPC, although not significantly lower than most other treatments. These studies are the first to demonstrate that the soil-applied fungicides prothioconazole and thiophanate-methyl may provide an additional field management option for Fusarium wilt of watermelon.     

黑龙江烟草病害种类鉴定及发生情况

为了明确黑龙江主要烟区目前病害发生和危害情况，于2010-2013年对黑龙江烟草主产区病害进行普查。鉴定结果表明，黑龙江烟草病害26种，其中真菌病害11种，细菌病害2种，病毒病害7种，寄生性种子植物1种，非侵染性病害5种；发生普遍且危害重的病害主要是烟草普通花叶病、角斑病。