厚朴药材研究进展

就厚朴的分布、生物学特性、化学成分、药理作用及提取方法进行综述,以期为厚朴的开发应用提供依据。     

Glyphosate-resistant weeds of South American cropping systems: an overview

Herbicide resistance is an evolutionary event resulting from intense herbicide selection over genetically diverse weed populations. In South America, orchard, cereal and legume cropping systems show a strong dependence on glyphosate to control weeds. The goal of this report is to review the current knowledge on cases of evolved glyphosate-resistant weeds in South American agriculture. The first reports of glyphosate resistance include populations of highly diverse taxa (Lolium multiflorum Lam., Conyza bonariensis L., C. canadensis L.). In all instances, resistance evolution followed intense glyphosate use in fruit fields of Chile and Brazil. In fruit orchards from Colombia, Parthenium hysterophorus L. has shown the ability to withstand high glyphosate rates. The recent appearance of glyphosate-resistant Sorghum halepense L. and Euphorbia heterophylla L. in glyphosate-resistant soybean fields of Argentina and Brazil, respectively, is of major concern. The evolution of glyphosate resistance has clearly taken place in those agroecosystems where glyphosate exerts a strong and continuous selection pressure on weeds. The massive adoption of no-till practices together with the utilization of glyphosate-resistant soybean crops are factors encouraging increase in glyphosate use. This phenomenon has been more evident in Argentina and Brazil. The exclusive reliance on glyphosate as the main tool for weed management results in agroecosystems biologically more prone to glyphosate resistance evolution.     

Pathogenesis of Eutypa lata in grapevine: identification of virulence factors and biochemical characterization of cordon dieback

Eutypa lata is a vascular pathogen of woody plants. In the present study we (i) determined which component(s) of the cell wall polymers were degraded in naturally infected grapevines and in artificially inoculated grape wood blocks; (ii) compared the pattern of wood decay in the tolerant grape cv. Merlot versus the susceptible cv. Cabernet Sauvignon; and (iii) identified secondary metabolites and hydrolytic enzymes expressed by E. lata during wood degradation. Biochemical analyses and a cytochemical study indicated that glucose-rich polymers were primary targets of E. lata. Structural glucose and xylose of the hemicellulose fraction of the plant cell wall and starch were depleted in infected woods identically in both cultivars. Moreover, the more tolerant cv. Merlot always had more lignin in the wood than the susceptible cv. Cabernet Sauvignon, indicating that this polymer may play a role in disease resistance. In vitro assays demonstrated the production by E. lata of oxidases, glycosidases and starch degrading enzymes. Phytotoxic secondary metabolites were also produced but our data suggest that they may bind to the wood. Finally, we demonstrated that free glucose in liquid cultures repressed primary but not secondary metabolism.     

广东丰顺县青蒿产业化发展现状与对策

丰顺县已初步建成一定规模的青蒿种植基地,产业化模式初见端倪。通过建立"GAP"规范,推行标准化生产,打造特色品牌和新型的社会化服务体系等对策,为青蒿的产业化经营和可持续发展提供保障。     

Seasonal stability in parasite assemblages of the Brazilian flathead, Percophis brasiliensis (Perciformes: Percophidae): predictable tools for stock identification

A comparison of the composition and structure of parasite communities of the Brazilian flathead, Percophis brasiliensis Quoy et Gaimard (Perciformes: Percophidae) among seasons during one year was carried out in the Argentine Sea. A total of 195 fish specimens were examined and 25 parasite species were found. Parasite communities in seasonal samples showed a high degree of homogeneity in taxonomic composition and infection levels. Similarity analysis showed that the seasonal stability within and between samples was constant in both the composition and community structure throughout the year. Parasites can, therefore, be considered predictable markers for fish stock identification, independently of the season of capture, at least on an annual scale.     

香蕉原生质体培养研究进展

本文综述了20多年来香蕉原生质体培养的研究概况;对影响香蕉原生质体分离、培养及植株再生因素进行了综述,并提出了香蕉原生质体培养研究展望。     

高产粳稻新品种“云粳30号”特征特性及栽培技术

云粳30号是云南省农业科学院粮食作物研究所选育的常规粳稻新品种,杂交组合为云粳15号×云粳优8号,于2011年通过云南省农作物品种委员会审定。1特征特性1.1农艺性状云粳30号属中熟粳稻,全生育期170 d。株高98cm,分蘖力强,最高茎蘖数555万个/hm2,株叶型好,叶色淡绿,耐肥抗倒,熟相好。     

玉米黑白膜同田对比试验研究

按照项目试验要求,安排6组黑白膜同田对比点进行试验.试验结果表明,黑膜覆盖比白膜覆盖有3点明显优势：一是茎宽、穗粗、穗长、百粒重等经济性状及产量黑膜均明显优于白膜;二是黑膜覆盖比白膜覆盖有极显著的控制杂草效果;三是黑膜覆盖不易烧苗,得到老百姓普遍认可.     

加拿大西部大麦的历史评价

为了评价加拿大西部１９１０－１９８７年间发放的春大麦品种的产量进展以及产量组份和农艺性状对产量所起的作用，１９８９－１９９０年在Ｂｏｔｈａ、ｌａｃｏｍｂｅ、Ｏｌｄｓ三个地点对２０个六棱和二棱栽培品种进行了试验。结果表明，籽粒产量每年增加１２．７－４１．４ｋｇ／ｈｍ＾２，收获指数每年增加０．０８－０．１７％，倒状每年减少０．０１－０．０５％，种子蛋白质含量每年减少０．０１－０．０２ｇ／ｋｇ。１９９０