Errors in Leaf Area Measurement with an Automatic Area Meter due to Leaf Chlorophyll in Crop Plants

This study revealed that an area meter with a semi-automaticfeeding mechanism underestimated the area of yellowish leavesand wavy leaves in crop plants. It is recommended that areameasurements should be made using photocopied leaves and leafsegments. The degree of underestimation should be checked whenchlorophyll meter (SPAD) values are less than 30.Copyright 1999Annals of Botany Company Glycine max Merr., Hordeum vulgare L., leaf area meter, leaf colour, Oryza sativa L.,Solanum tuberosum L., SPAD, Triticum aestivum L., Zea mays L.     

Development and characteristics of microsatellite markers in Pinus merkusii

Pinus merkusii is an important industrial species that is distributed only in Southeast Asia. We isolated 10 microsatellite markers from this species using a dual‐suppression‐polymerase chain reaction technique. Of these markers, five loci were codominant and polymorphic. The number of alleles per locus ranged from three to six and the expected heterozygosity ranged from 0.389 to 0.728. These microsatellite markers will be available for analysis on population genetics and mating patterns.     

农杆菌介导的玉米大斑病菌转化

采用玉米大斑病菌Exserohilum turcicum的无性菌丝作受体,建立了农杆菌Agrobacterium tumefaciens介导的转化方法。采用的载体为 pUR5750, 携有来源于质粒pAN71的潮霉素抗性选择标记。PCR分析表明T-DNA 插入到E. turcicum基因组中。     

Life history and host specificity of the Japanese flea beetles Trachyaphthona sordida and T. nigrita (Coleoptera: Chrysomelidae), potential biological control agents against skunk vine, Paederia foetida (Rubiaceae), in the southeastern parts of the United States and Hawaii

Skunk vine, Paederia foetida (Rubiaceae), is native to Asia and has been recognized as an invasive weedy vine of natural areas in Florida and Hawaii. Two insects, Trachyaphthona sordida and Trachyaphthona nigrita (Coleoptera: Chrysomelidae) from Japan are being considered as potential biological control agents against skunk vine. To gather fundamental information on their biology, we carried out field surveys and laboratory experiments in Kyushu, southern Japan, between 2003 and 2006. We found that T. sordida is commonly distributed in Kyushu and T. nigrita is restricted to the southern parts of Kagoshima Prefecture on the southern part of Kyushu. These species are fundamentally univoltine and adults appear in late April to early July. Trachyaphthona sordida overwinters as mature larvae and T. nigrita as mature larvae or rarely as adults. Larvae of both species feed on fine roots of P. foetida in the field and Serissa foetida (Rubiaceae) under rearing conditions, and they appear to have tribe‐level host specificity in their host range. On the basis of these results, we suggest that both species are suitable as biological control agents.     

玉米大斑病菌(Exserohilum turcicum)原生质体的分离及转化

玉米大斑病是严重危害玉米生产的一个世界性真菌病害。由于玉米大斑病菌(Exserohilum turcicum)在无性生长过程中迅速产生黑色素,致使原生质体难以分离。测试了包括Fungase、Funcelase、Novozyme、Glucanex、Driselase、Uskizyme、Kitalase在内的7种细胞壁降解酶及其组合、病原菌菌株和培养基对原生质体分离效果的影响。结果表明菌株的培养形态和菌丝的生长状态显著影响原生质体的分离效率;酶组合Kitalase Glucanex Driselase,Kitalase Glucanex和Kitalase Uskizyme能够有效地分离玉米大斑病菌的原生质体。初步的转化试验表明,质粒pAN71可以用于该病原菌的转化。这些结果将为E．turcicum和Exserohium属其它真菌的基因克隆提供一些有用的信息。     

Species‐specific mitochondrial gene rearrangements in biting midges and vector species identification

Abstract Partial mitochondrial gene sequences of 16 Culicoides species were determined to elucidate phylogenetic relations among species and to develop a molecular identification method for important virus vector species. In addition, the analysis found mitochondrial gene rearrangement in several species. Sequences of the mitochondrial genome region, cox1–trnL2–cox2 (1940–3785 bp) of 16 Culicoides and additional sequences were determined in some species, including whole mitochondrial genome sequences of Culicoides arakawae. Nine species showed common organization in this region, with three genes cox1–trnL2–cox2 and a small or no intergenic region (0–30 bp) between them. The other seven species showed translocation of tRNA and protein‐coding genes and/or insertion of AT‐rich non‐coding sequences (65–1846 bp) between the genes. The varied gene rearrangements among species within a genus is very rare for mitochondrial genome organization. Phylogenetic analyses based on the sequences of cox1+cox2 suggest a few clades among Japanese Culicoides species. No relationships between phylogenetic closeness and mitochondrial gene rearrangements were observed. Sequence data were used to establish a polymerase chain reaction tool to distinguish three important vector species from other Culicoides species, for which classification during larval stages is not advanced and identification is difficult.