中国沿海河口地区鳗苗的群体生态和群体结构

本报道了１９９２－１９９５年间对中国沿上代表性河口鳗苗的群体生态（包括溯河的生态条件，日龄生长、食性、对温度和盐度变化的适应力、耗氧率、室息点、耐铠力）和群体结构（全长、体重和日龄结构）的研究结果。     

Sporadic endemicity of zoonotic Paragonimus in raccoon dogs and Japanese badgers from Miyazaki Prefecture,Japan

Paragonimiasis is a zoonotic trematode infection caused by Paragonimus spp. To determine the recent status of Paragonimus infections in wild animals, this study investigated Paragonimus spp. in 39 raccoon dogs and 54 Japanese badgers from March 2019 to January 2021 in Miyazaki Prefecture, and examined metacercariae in freshwater crabs. Triploid P. westermani was found in one raccoon dog (2.6%), and metacercariae were recovered from Eriocheir japonica captured near the infected animal collected. One Japanese badger (1.9%) harbored P. skrjabini miyazakii; this prevalence was lower than the approximately 30% that was reported in the 1970s. Results indicated that zoonotic Paragonimus was sporadically prevalent in wild animals. Further investigation in various animals is awaited to elucidate current wildlife reservoirs for those Paragonimus.     

灌溉方式对温室樱桃番茄结果期根系特征与产量的影响

采用小区试验研究了不同灌溉方式对樱桃番茄结果期根系特性与产量的影响。试验设置了6个灌溉方式处理,即:处理Ⅰ,常规沟灌,种植行和操作行同时灌溉;处理Ⅱ,交替沟灌,种植行和操作行交替灌溉;处理Ⅲ,固定灌种植行;处理Ⅳ,固定灌操作行;处理Ⅴ,前期常规沟灌,结果期交替沟灌;处理Ⅵ,前期交替沟灌,结果期常规沟灌。结果表明,不同灌溉方式之间樱桃番茄根系的特征值差异达到显著水平,处理Ⅵ根体积显著高于其余5种处理,根系伤流量为22.37 mg/min,根系活力高达0.50 mg/(g.h)。灌溉方式对樱桃番茄单果重、产量有显著影响,前期交替沟灌结果期常规沟灌(处理Ⅵ)的单果重与产量均高于其他处理。因此,前期交替沟灌结果期常规沟灌有利于樱桃番茄根系的发育与产量的提高。     

日本金竹文化论

日本的金竹文化鲜明体现在古代战争、传统节日、文学等方面,具有历史悠久、内涵深刻、表现广泛等特点。近代以后金竹文化低迷,但仍然是日本竹文化中最具神圣文化内涵的部分。     

大连地区大樱桃常见缺素症状及防治对策

大樱桃是多年生木本果树,其根系分布较浅,且养分需求比较集中,常造成某些养分的缺乏。近年来在大连地区大樱桃种植区走访调查发现,钾、锰、镁、硼、铁等养分的缺素现象比较多,因此针对大樱桃以上缺素症状的识别和采取相应的防治对策是很有必要的,同时针对樱桃缺素发生的原因进行了深入的分析,以便于系统的对樱桃缺素进行综合防治。     

日本落叶松人工林生长预测的全林分模型研究

以长岭岗林场日本落叶松人工林中的固定样地以及临时样地调查数据为基础，从模型间的相容性出发，建立了包含立地指数SI、林分密度SDI、林分断面积生长模型、树高曲线动态模型和林分收获模型的全林分模型系统，着重探讨了用Korf方程构造林分断面积生长模型时有关参数与SI和SDI的关系。     

双层棚架式栽培的日本梨品种光合特性初探

以双层棚架式栽培条件下的7个日本梨(Pyrus pyrifolia Nakai)品种为试材,采用Li-6400便携式光合作用测定系统,对各品种的光合特性进行了比较研究,结果表明,日本梨品种喜水、新高、清澄为光合能力和干物质积累能力较高、水分需求量较多的类型,秋荣较低,筑水、幸水、丰水的光合能力和水分消耗都属中等,而秋荣属于光合能力和水分消耗均较低的类型.建议在日照充足、灌溉条件好的地方发展日本梨可选喜水、新高、清澄,而灌溉条件较差的地方可选秋荣.整形方式可采用双层棚架式.     

Molecular characterisation of Berberis thunbergii cultivars using microsatellite markers

Due to a growing concern for black stem rust (BSR) disease in wheat-producing regions of the USA and Canada, the sale and movement of barberry plants to ‘quarantined’ regions is restricted to just a few cultivars approved as being BSR-resistant. Currently, verification of a given barberry plant as being ‘true-to-type’ of the approved cultivar relies on comparing its morphological features with those of its reference cultivar. Frequently, this approach leads to mis-identification of cultivars due to the similarity of morphological features among young plants. The approach is complicated, or not at all useful, when the plants are dormant, which is the stage at which plants are sold. A reliable technique that could be used at any stage of plant growth to identify and verify cultivars is needed. In this study, the genetic diversity of 51 barberry cultivars was assessed using microsatellite markers, and their genotypic profiles were developed based on the allele composition of different microsatellite loci. A total of 43 alleles were generated at seven microsatellite loci, and all were polymorphic. An unweighted pair group method with arithmetic averaging (UPGMA) cluster analysis of the Jaccard’s coefficient of similarity matrix showed that 84.3% of the 51 cultivars tested were distinct from each other. Ten of the 11 cultivars approved for import into Canada were distinguishable based on their genotypic profiles. The results indicated that microsatellite-based genotyping could be used by regulatory agencies to identify and offer ‘true-to-type’ guarantees to cultivars destined for BSR ‘quarantined’ regions, and to verify the uniqueness of new cultivars when issuing Plant Patents.     

New potyvirus isolated from <Emphasis Type="Italic">Cryptotaenia japonica</Emphasis>

 A potyvirus, for which the name Japanese hornwort mosaic virus (JHMV) is proposed, was isolated from Japanese hornwort plants (Cryptotaenia japonica) with mosaic disease symptoms. The virus was used to inoculate mechanically 34 plants belonging to 33 species of 10 families. Of these species seven from two families were infected. Faint chlorotic spots appeared on the inoculated leaves of Chenopodium quinoa and C. amaranticolor, but no systemic infection occurred in these plants. JHMV systemically infected only Umbelliferae plants; they did not infect 26 other species in eight families. JHMV was transmitted in a nonpersistent manner by aphids (Myzus persicae). The virus was a flexuous rod-shaped particle about 750 nm in length. Sequencing the nucleotides in the 3′ terminal region of JHMV revealed that the coat protein contains 280 amino acids with a molecular mass of 32.2 kDa. The nucleotide sequence of the coat protein of JHMV had the highest similarity with that of Zantedeschia mosaic virus (83.3%) compared to those of other potyviruses (57.0%–64.9%). An antiserum against JHMV reacted strongly with JHMV and weakly with Potato virus Y. These results indicate that JHMV is a new potyvirus. Received: September 9, 2002 / Accepted: November 7, 2002 RID="*" ID="*" The nucleotide sequence determined in this work appears in the DDBJ/EMBL/GenBank nucleotide sequence databases with the accession number AB081518     

Ultrastructural study on scab resistance expressed in epidermal pectin layers of pear leaves

Proliferation and collapse of subcuticular hyphae of Venturia nashicola race 1 were studied ultrastructurally, after inoculation of susceptible Japanese pear cv. Kousui, resistant Japanese pear cv. Kinchaku, resistant Asian pear strain Mamenashi 12 and nonhost European pear cv. Flemish Beauty leaves, to understand the nature of the resistance mechanism. After cuticle penetration by the pathogen, the hyphae were observed at lower frequency in epidermal pectin layers and middle lamellae of leaves of the three resistant plants than in those of susceptible ones. This result suggested that fungal growth was suppressed in the incompatible interaction between pear and V. nashicola race 1. In the pectin layers of all inoculated plants, some hyphae had modifications such as breaks in the plasmalemma with plasmolysis, necrotic cytoplasm and degraded cell walls. More hyphae had collapsed in the leaves of the three resistant plants than in those of the susceptible cv. Kousui. In collapsed hyphae, the polymerized cell walls broke into numerous fibrous and amorphous pieces, showing that the scab resistance might be associated with cell wall-degrading enzymes from pear plants.