温室快速鉴定花生根结线虫病抗性新方法

为了通过对花生抗线虫鉴定方法的比较,确定更加快速有效的抗性鉴定技术,作者于2002～2003年在佐治亚大学的Tifton试验站进行了温室盆栽试验。结果表明,侵染期幼虫与虫卵均可用于花生抗线性鉴定的温室接种,但与使用虫卵接种相比,以侵染期幼虫作为接种体需要多花3～5d的时间收集幼虫;接种后14d,可以依据0～5级的虫瘿分级标准将供试的4份花生种质区分开来;接种后6～10周依据卵块数量或每克根中的虫卵数可以进一步确认花生的抗性水平。虫瘿级数、虫瘿数量、卵块数量及每克根中的卵量之间存在着极显著(P<0.01)的正相关关系。根据研究结果提出了温室中花生抗线虫鉴定的程序方法:以8000粒卵/株为适宜接种量,接种后14d依据0～5级的虫瘿分级标准进行初筛,对初筛入选的材料再在接种后6周根据卵块数量或卵量验证其抗性。     

Genomic-SSR 和EST-SSR在柱花草种间的遗传差异

为了探讨genomic-SSR与EST-SSR标记在柱花草种间的遗传差异,利用两种SSR标记技术,对来自不同种的12份柱花草种质进行了遗传分析,并对两种不同标记进行比较.结果表明:EST-SSR标记相比genomic-SSR在柱花草不同种间具有更好的通用性,EST-SSR检测到的等位基因数和PIC指数平均值分别是4.6和0.610,genomic-SSR检测到的等位基因数和PIC指数平均值分别是5.6和0.702.聚类结果表明,genomic-SSR和EST-SSR均能有效鉴别所有供试柱花草种质.     

Feeding ecology of dominant demersal fish species <Emphasis Type="Italic">Favonigobius gymnauchen,Repomucenus</Emphasis> spp. and <Emphasis Type="Italic">Tarphops oligolepis</Emphasis> at a sandy beach where larval Japanese flounder settle in the Seto Inland Sea,Japan

ABSTRACT:   Feeding habits of Favonigobius gymnauchen , Repomucenus spp. and Tarphops oligolepis were examined during the period from May to August in 1999, 2000 and 2001 at a sandy beach in the central Seto Inland Sea, Japan. The three species of fish accounted for more than 60% of all fish collected in terms of number of individuals. All three species mainly consumed small crustaceans. However, the major prey of F .  gymnauchen and Repomucenus spp. differed from that of T .  oligolepis . F .  gymnauchen and Repomucenus spp. mainly consumed mysids and small crangonid shrimp (<12 mm in body length), which predominated in the study area. T .  oligolepis actively selected only epifaunal mysids Nipponomysis ornata and avoided crangonid shrimp and gammarids . The frequencies of occurrence of fish in the guts of the three dominant species were very low, and larval and juvenile Japanese flounder were not observed in any of the three fish species. The diet of juvenile Japanese flounder was similar to that of the three species. From these results, it appears that these three fish are competing species for the flounder.     

Effects of temperature, salinity, desiccation and chemical treatments on egg embryonation and hatching success of Benedenia seriolae (Monogenea: Capsalidae), a parasite of farmed Seriola spp

The effects of temperature and salinity on the embryonation period and hatching success of eggs of Benedenia seriolae were investigated. Temperature strongly influenced embryonation period; eggs first hatched 5 days after laying at 28 degrees C and 16 days after laying at 14 degrees C. The relationship between temperature and embryonation period is described by quadratic regression equations for time to first and last hatching. Hatching success was >70% for B. seriolae eggs incubated at temperatures from 14 to 28 degrees C. However, no B. seriolae eggs embryonated and hatched at 30 degrees C and <2% of eggs hatched when incubated at 24 degrees C after transfer to 30 degrees C for 48 h. Embryonation period was similar for eggs incubated in sea water at 25, 30 and 35 per thousand salinity, but increased for eggs incubated at higher or lower salinities. When incubated at salinities ranging from 25 to 45 per thousand, more than 70% of B. seriolae eggs embryonated and hatched. Hatching success was lower at 20 and 50 per thousand salinity and few or no eggs hatched at 10 and 15 per thousand. Hatching of B. seriolae eggs can be prevented by desiccation for 3 min, by immersion in water at 50 degrees C for 30 s or by treatment with 25% ethanol for 3 min.     

鱼类腐败菌不同生长动力学温度模型的可靠性评价和比较

探讨和比较了Arrhenius方程和Belehradek方程两种腐败菌生长动力学温度模型预测鱼鲜度和货架期的可靠性。结果表明，两种温度模型都能很好地预测罗非鱼中假单胞菌的生长动态和预报货架期，通过假单胞菌生长动力学模型的预测值，与罗非鱼中假单胞菌生长的实测值比较，偏差度在0．95～1．01之间，准确度在1．02～1．06之间，两种温度模型相比，Belehradek温度模型的可靠性更好。罗非鱼在3和8℃贮藏中货架期实测值与利用Arrhenius方程和Belehradek方程建立的假单胞菌生长动力学温度模型求得的预测值的比较，Arrhenius温度模型预测值和实测值的相对误差分别为11．8％和8．00％，Belehradek温度模型预测值和实测值的相对误差分别为3．47％和一7．91％，两种温度模型相比，Belehradek温度模型的结果更为理想。     

Catch and trade bans for seahorses can be negated by non-selective fisheries

1. All seahorse species (genus Hippocampus) are listed under Schedule I of India's Wild Life Protection Act, making all capture and trade of seahorses illegal. In the more than 15 years since the ban, little work has been done to assess its effects on seahorse conservation.
2. Between 2015 and 2017, fisheries and trade surveys were conducted along the south-east coast of India, in the state of Tamil Nadu, historically known to be a hub for seahorse catches and trade.
3. Seahorses were primarily landed as bycatch, although in greater quantities by traditional drag nets than as trawl bycatch. Total annual catches were estimated between 4.98 million and 13.64 million seahorses, 87% of which were caught by active non-selective gear.
4. Generalized additive models revealed that seahorse catch per unit effort had non-linear relations with depth and latitude, and were higher in biogenic habitats, with active, bottom-used, and non-selective gears (e.g. trawls).
5. The illegal nature of the trade in seahorses hampered an understanding of trade routes and trade volumes. Catch estimates indicated that 11.21–30.31 tonnes of seahorses probably entered trade, yet interviews with traders only documented trade of about 1.6 tonnes.
6. Fishers reported a decreasing availability of seahorses. Since most seahorses come from bycatch in persistent fisheries that are not directly affected by the ban on seahorse capture, this decline is likely to represent a population decline.
7. A fishery and trade ban for incidentally caught species, particularly in a poorly regulated fishery, appears to add little conservation value. There needs to be a shift in the management approach, moving from a ban towards spatial and temporal restrictions, and toward enforcing existing fishery regulations.

     

中国沿海两例食用织纹螺中毒事件中织纹螺体内毒素分析

近年来,因食用织纹螺(Nassariusspp.)导致的中毒事件在中国沿海屡有发生。由于中毒患者的症状与麻痹性贝毒中毒症状相似,因此,许多中毒事件被归咎于麻痹性贝毒,认为织纹螺中的毒素与邻近海域的有毒赤潮有关,但也有研究发现螺体内存在河豚毒素。对此,本研究应用亲水性相互作用色谱柱建立了河豚毒素的液相色谱-质谱联用分析方法,对造成2002年和2003年两次中毒事件的织纹螺样品进行分析。结果表明,两批织纹螺样品中均含有高浓度的河豚毒素及其衍生物,包括三脱氧河豚毒素、脱水河豚毒素和单加氧河豚毒素等,而且两个织纹螺样品中的毒素组成非常相似。因此,导致这两起中毒事件的致毒因子是河豚毒素及其衍生物。江苏和福建两地织纹螺中毒素组成的相似性显示两地织纹螺可能具有相同或相近的毒素来源。     

圆盘豆热处理材光稳定性的研究

采用热处理和氙灯照射对圆盘豆木材颜色的变化进行研究,以CIE(1976)L*a*b*表色系统表色,分析木材热处理前后、氙灯照射前后颜色变化。结果表明,热处理后木材颜色加深。随着氙灯照射时间延长,未处理材表面颜色逐渐加深,色差△E*逐渐增大。热处理材表面颜色变化不大,色差△E*值变化较小,这表明与未处理材相比,热处理材光稳定性能更好。     

线虫寄生菌巴斯德杆菌的生物多样性研究进展

巴斯德杆菌(Pasteuriaspp. )是一类结构特殊且能产芽孢的革兰氏阳性菌,能寄生于多种重要的植物病原线虫,在控制线虫群体方面效果明显.作为一类线虫寄生菌,该菌属内种间、分离物间、种与分离物之间在表型特征、寄主范围、遗传本质等多方面存在差异,并呈现出较为明显的多样性.本文就该菌的生物多样性研究状况作一总结,并阐明其在线虫生防中的意义.     

枯草芽孢杆菌SB1的抑菌活性及其对番茄青枯病的防治作用

 Bacillus subtilis strain SB1 isolated from tomato roots was evaluated for its ability to control tomato bacterial wilt under greenhouse conditions.Application of strain SB1 culture suspension suppressed tomato wilt disease both in sterilized and non-sterilized soil,providing 76.03% and 77.78% protection,respectively.Wilt symptom was significantly reduced when strain SB1 was applied before pathogen inoculation,while less suppression was conferred by strain SB1 application after pathogen inoculati...