Components of resistance to late leaf spot and rust among interspecific derivatives and their significance in a foliar disease resistance breeding in groundnut (Arachis hypogaea L.)

Late leaf spot (LLS) and rust cause substantial yield losses and reduce the fodder and seed quality in groundnut (Arachis hypogaea L.). Adoption of resistant cultivars by the semi-arid tropic farmers is the best option to overcome yield losses. Knowledge on components of resistance to these diseases should facilitate the development of groundnut cultivars with enhanced resistance to LLS and rust. The objectives of the experiments were to study the genetic variability and relationships among components of resistance to LLS and rust, and assess their significance in disease resistance breeding. Fifteen interspecific derivatives for LLS and 14 for rust and a susceptible control, TMV 2, were evaluated in a randomised complete block design with two or three replications under greenhouse conditions. The experiments were repeated twice. Genotypic differences were highly significant for all the traits studied. Resistance to LLS is due to longer incubation and latent periods, lesser lesions per leaf, smaller lesion diameter, lower sporulation index, and lesser leaf area damage and disease score. Selection based on components of resistance to LLS may not lead to plants with higher retained green leaf area. The remaining green leaf area on the plant should, therefore, be the major selection criteria for resistance to LLS in breeding programs. Resistance to rust is due to longer incubation and latent periods, fewer pustules per leaf, smaller pustule diameter, lower sporulation index, and lesser leaf area damage and disease score. Rust resistant components appear to work additively, therefore, selection based on resistance components together with green leaf area retained on the plant should be the basis of selecting for resistance to rust in breeding programs. ICGV 99005, 99003, 99012, and 99015 for rust and ICGV 99006, 99013, 99004, 99003, and 99001 for LLS are the better parents for use in resistance breeding programs. This revised version was published online in July 2006 with corrections to the Cover Date.     

稀土（Nd,Pr）（Ⅲ）双酞菁衍生物的合成,表征和成膜性

本文介绍四种新的稀土（Ｎｄ，Ｐｒ）（Ⅲ）双酞菁衍生物合成：八－４－（四氢糖氧基）钕（Ⅲ）（Ａ）；八－４－（β－萘氧基）钕（Ⅲ）（Ｂ）；八－４－（２，４－二特戊基苯氧基）钕（Ⅲ）（Ｃ）：八－４－（２，４－二特戊基苯氧基）镨（Ⅲ）（Ｄ）；并通过元素分析红外光谱，核磁共振谱加以确认。     

4-羟基-3-甲氧基肉桂酸衍生物除草活性研究

为了寻找新的除草活性化合物,利用茎叶处理、叶绿体光密度测定及相对电导率测定等方法对天然产物4-羟基-3-甲氧基肉桂酸及其3个衍生物进行了除草活性研究。结果表明:4-羟基-3-甲氧基肉桂酸、4-羟基-3-甲氧基肉桂酸酰肼、4-乙酰氧基-3-甲氧基肉桂酸和4-羟基-3-甲氧基肉桂酸乙酯在光照条件下对马唐的抑制中浓度(IC50)分别为4.31,1.97,4.26和0.67mg/mL;黑暗条件下分别为2.65,0.83,2.54和0.36mg/mL;4-乙酰氧基-3-甲氧基肉桂酸对马唐叶绿体光密度的影响呈上升趋势;4-羟基-3-甲氧基肉桂酸酰肼、4-乙酰氧基-3-甲氧基肉桂酸和4-羟基-3-甲氧基肉桂酸乙酯处理后,马唐的相对电导率分别增加了19.24%,11.96%和18.33%。可见这3个衍生物的除草活性均高于母体化合物。     

金融衍生工具风险及防范

金融衍生工具存在着市场、信用、流动性、操作和交易风险。应通过完善衍生工具法制建设,实施动态监管,严格金融衍生工具合约设计,使其标准化、规范化,确保衍生工具交易的公开、公平。应加强衍生工具法律风险防范的国际合作,以防范和规避金融衍生工具风险。     

Cherbonolides M and N from a Formosan Soft Coral Sarcophyton cherbonnieri

Two new isosarcophine derivatives, cherbonolides M (1) and N (2), were further isolated from a Formosan soft coral Sarcophyton cherbonnieri. The planar structure and relative configuration of both compounds were established by the detailed analysis of the IR, MS, and 1D and 2D NMR data. Further, the absolute configuration of both compounds was determined by the comparison of CD spectra with that of isosarcophine (3). Notably, cherbonolide N (2) possesses the unique cembranoidal scaffold of tetrahydrooxepane with the 12,17-ether linkage fusing with a γ-lactone. In addition, the assay for cytotoxicity of both new compounds revealed that they showed to be noncytotoxic toward the proliferation of A549, DLD-1, and HuCCT-1 cell lines. Moreover, the anti-inflammatory activities of both metabolites were carried out by measuring the N-formyl-methionyl-leucyl-phenylalanine/cytochalasin B (fMLF/CB)-induced generation of superoxide anion and elastase release in the primary human neutrophils. Cherbonolide N (2) was found to reduce the generation of superoxide anion (20.6 ± 6.8%) and the elastase release (30.1 ± 3.3%) in the fMLF/CB-induced human neutrophils at a concentration of 30 μM.     

小麦 中间偃麦草衍生后代的细胞学和SSR标记鉴定

为了鉴定小麦与八倍体小偃麦的杂交组合NZ2W5的衍生后代中是否含有中间偃麦草的遗传物质,利用细胞学和SSR技术对该组合的12个衍生单株进行了鉴定.结果表明,NZ2W5组合衍生后代的根尖细胞染色体数目均为2n=42,花粉母细胞减数分裂中期Ⅰ染色体构型均为2n=21Ⅱ.以相关亲本中间偃麦草、小麦-中间偃麦草部分双二倍体远中2、普通小麦合作2号和阿勃以及衍生后代为材料,选取均匀分布于小麦各条染色体上的480个SSR标记进行分析,结果表明,Xbarc008、Xbarc195、Xwmc489、Xcfb3440、Xwmc331和Xgwm608等20个标记在中间偃麦草中具有特异条带,其中定位在小麦4D染色体上的标记Xwmc331可以在NZ2W5组合衍生的12个单株中检测到中间偃麦草119 bp的特异条带.研究结果表明,NZ2W5组合衍生后代的细胞遗传学基本稳定,携带中间偃麦草的遗传物质,涉及的外缘遗传物质可能同源于小麦的第四部分同源群.     

小麦-卵穗山羊草衍生后代的SSR分子标记鉴定和白粉病抗性评价

山羊草属植物是普通小麦改良过程中重要的有益基因来源,小麦的许多抗病虫、抗逆基因都来源于山羊草属植物。本研究利用杂交和回交的方法,成功获得了19株小麦-卵穗山羊草衍生后代,实验选取均匀分布于小麦各条染色体的SSR标记400个,对三个亲本(中国春、卵穗山羊草和陕优225)以及19株衍生后代进行分子标记特异性分析,结果表明,341个标记可以在卵穗山羊草中扩增出条带,说明SSR标记在山羊草中位点丰富;20个标记可以在卵穗山羊草中扩增出特异条带,说明在卵穗山羊草中有不同于另外两个亲本的特异SSR位点;将20个在卵穗山羊草亲本中有特异条带的标记应用于19株衍生后代中,发现有10个标记可以在衍生后代中扩增出特异条带,说明19株衍生后代中全部含有卵穗山羊草的遗传物质,这些特异引物可以继续应用于后代的检测中。本实验还对3个亲本材料和19株衍生后代进行了成株期白粉病抗性鉴定,结果显示,中国春和陕优225都是9级高感,卵穗山羊草是0级免疫,19株衍生后代中有3株(1-1,1-2,1-3)分别是7、8和8级感病,其余均为0级免疫,说明衍生后代的白粉病抗性完全遗传自卵穗山羊草亲本。     

-石竹烯及其衍生物的生物活性与合成研究进展

综述了β-石竹烯及其衍生物的活性及合成方法。在活性方面,β-石竹烯作为香料已经被应用于化妆品和食品添加剂中,药理研究表明β-石竹烯具有局麻作用、抗炎作用、驱蚊虫作用、抗焦虑、抗抑郁作用,β-石竹烯醇还应用于镇咳祛痰药物中,石竹烯氧化物具有镇痛和抗炎作用,抗真菌作用,还有细胞毒性等。同时还简单介绍了β-石竹烯及其部分衍生物的合成方法。     

Assessment of genetic diversity among selected groundnut germplasm. I: RAPD analysis

Assessment of genetic diversity in a crop species is prerequisite to its improvement. The use of germplasm with distinct DNA profiles will help to generate genetically diversified breeding populations. The aims of the present experiment were to study molecular diversity among selected groundnut accessions and identify those with distinct DNA profiles for mapping and genetic enhancement. Twenty‐six accessions and eight primers of a 10‐mer were selected for random amplified polymorphic DNA assay. The genetic similarity (S_ij) ranged from 59.0% to 98.8%, with an average of 86.2%. Both multidimensional scaling and unweighted pair‐group method with arithmetic averages (UPGMA) dendrograms revealed the existence of five distinct clusters. However, this classification could not be related to known biological information about the accessions falling into different clusters. Some accessions with diverse DNA profiles (ICG 1448, 7101, and 1471, and ICGV 99006 and 99014) were identified for mapping and genetic enhancement in groundnut.