The genome donors of the groundnut/peanut (Arachis hypogaea L.) revisited

Arachis hypogaea, the cultivated groundnut is a tetraploid with an AABB genomic constitution. The available literature on the origin of groundnut reveals that there is general agreement that the cultivated groundnut has evolved from the wild tetraploid species A. monticola, with which it crosses freely to produce fertile hybrids. However, the issue of actual diploid ancestors of A. monticola is still unresolved. Both cytogenetic and molecular evidences support A. duranensis being the most probable progenitor and donor of the A genome to A. hypogaea. For the B genome, the cytogenetic evidence suggests A. batizocoi to be the most probable progenitor, but the RFLP banding pattern indicates that A. batizocoi is more distantly related to A. hypogaea than other species of section Arachis. RFLP banding pattern indicates A. ipaensis to be one of the closest species to A. hypogaea and the possible donor of the B genome. The present article critically analyzes the available data, which suggests that until an amphidiploid is produced synthetically between A. duranensis × A. ipaensis and crossed successfully with A. hypogaea to produce a fertile hybrid, this issue would remain unresolved. A. batizocoi would remain the most probable donor of the B genome because of its directly demonstrable cytogenetic affinity.     

Resistance to Meloidogyne javanica in wild Arachis species*

The root-knot nematode, Meloidogyne javanica Race 3 is an important nematode parasite of groundnut. Greenhouse evaluation of 184 accessions of 33 wild Arachis spp. five interspecific derivatives, 18 groundnut cultivars for root damage (galls formed by nematode) and nematode reproduction demonstrated that resistance to the nematode is available in the genepool of wild Arachis spp. Seven accessions, ICG 8952 (Arachis helodes), ICC 13211 (A. sylvestris), ICG 13224 (A. kretscmeri), ICG 13231 (Arachis sp.), ICG 14862 (A. kuhlmannii), ICG 14868 (A. stenosperma), and ICG 14915 (A. sylvestris) were highly resistant to nematode reproduction and root damage. There was no gall and eggmass formation on any plant of these accessions. Thirty-three accessions were resistant and 14 were moderately resistant. All the tested accessions of A. monticola, A. benensis, A. ipaensis, A. hoehnei, A. kempff-mercadoi, A. valida, A. chiquitana, A. rigonii, A. vallsii, A. dardani, A. paraguariensis, A. triseminata, interspecific derivatives, and groundnut cultivars were susceptible. The possible use of resistance sources in the breeding program is discussed.     

Chemical composition and biological activities of Arachis species

Arachis hypogaea , known as the peanut, is native to South America. Peanut contains several active components including flavonoids, phenolic acids, phytosterols, alkaloids, and stilbenes. Some therapeutic effects have been reported for peanut seed extracts, such as antioxidative, antibacterial, antifungal, and anti-inflammatory activities. This paper aims to give an overview of the chemical composition, focusing on secondary metabolites, and of the biological activity of A. hypogaea, to stimulate new studies about species of the Arachis genus.     

红壤缓坡花生地不同水土保持措施效果分析

采用径流小区试验,以花生常规种植为对照,研究红壤荒坡花生地花生+草篱、花生+覆盖+草篱、花生+覆盖3种种植措施的水土保持效果.试验从4月份花生种植后开始测定,8月底花生收获结束.结果表明:1)3种种值措施地表径流量均随日降雨量的增大而增大;2)3种种植措施地表径流量、土壤侵蚀量均与对照差异显著(P＜0.01).表明,花...     

Study of the genetic variability and similarity among and within Arachis villosulicarpa, A. pietrarellii and A. hypogaea through isoenzyme analysis

Arachis villosulicarpa is a perennial species cultivated for its soft and tasty seeds by indigenous inhabitants of the Mato Grosso State, Brazil. Besides A. hypogaea, this species is considered as the only species of Arachis which represents a valuable food source for human consumption. Due to the lack of knowledge concerning the genetic diversity of A. villosulicarpa, this study was conducted to evaluate the genetic variability of the accessions from the Germplasm Collection of CENARGEN/EMBRAPA (Brasília, DF, Brazil) and Instituto Agrono^mico (IAC, Campinas, SP, Brazil). In addition, the genetic similarity between A. villosulicarpa, the related wild species A. pietrarellii, and the cultivated peanut A. hypogaea cv. Tatu was evaluated. From the entire sample analyzed of A. villosulicarpa, the accession from Instituto Agrono^mico showed the highest indices of diversity for both enzymatic systems analyzed, pointing this accession as a promising source of genetic variabil ity that must be preserved in the Germplasm Bank. A high level of genetic similarity was observed between A. pietrarellii and A. villosulicarpa, supporting previous suggestions that A. pietrarellii could be the ancestral progenitor species of A. villosulicarpa or that both species originated from a common ancestor.     

沂蒙山区坡耕花生地垄间植草对土壤理化性质的影响

以沂蒙山区坡耕花生地为研究对象,建立野外原位观测小区,将花生+狗牙根(处理Ⅰ)、花生+草木犀(处理Ⅱ)、花生+黑麦草(处理Ⅲ)、花生+三叶草(处理Ⅳ)、花生+空白对照(处理Ⅴ)5种植草方式进行对比,研究垄间不同植草方式对坡耕花生地土壤理化性质的影响,并运用灰色关联分析法对多个土壤理化性质指标进行综合判定。结果表明:垄间植草方式中土壤粗化指数、砂粒含量、总孔隙度、毛管孔隙度、毛管持水量、有机质及全氮含量出现了不同程度的升高,而容重、黏粒与粉粒、全磷含量呈现下降趋势;与空白对照相比,垄间植草明显改良了土壤理化性质,其中以花生+黑麦草处理效果最优,灰色关联度达到0.931 9,其余依次为花生+三叶草(0.929 6)、花生+草木犀(0.747 6)及花生+狗牙根(0.731 1),空白对照效果最差,灰色关联度仅为0.548 7。     

New peanut (Arachis hypogaea) phytoalexin with prenylated benzenoid and but-2-enolide moieties

A new pigmented, optically active, low molecular weight metabolite has been isolated from peanut (Arachis hypogaea) kernels challenged by four species of Aspergillus. The structure of the new compound, termed SB-1, was elucidated by analysis of 1H NMR, 13C NMR, and mass spectrometric data. The SB-1 molecule bears prenylated benzenoid and but-2-enolide moieties and represents an unusual class of compounds. The closest known analogue to SB-1 was isolated from heartwood of Pericopsis elata. Both A. hypogaea and P. elata belong to the family Leguminosae. The new metabolite was accumulated in different peanut genotypes challenged by five Aspergillus species and may be an important representative of a new class of peanut phytoalexins. SB-1 production often exceeds production of major known stilbenes.     

Genetic variation vis-à-vis molecular polymorphism in groundnut, Arachis hypogaea L.

Recent studies on the genus Arachis using molecular markers have revealed very little demonstrable polymorphism in the cultivated groundnut, A. hypogaea. This has led to the hasty generalization that the groundnut lacks genetic variation. However, this is in complete contradiction to the results of other lines of investigations into the origin and evolution of A. hypogaea. Further, a characterization of the world collection for various traits also shows significant levels of variation for almost all genetic traits. The literature review in this article suggests that the lack of genetic variation was inferred because of an inadequacy in the material studied, and the range of techniques used to study molecular polymorphism. A comprehensive and rigorous examination of the material available in the groundnut world collection, either by improving current techniques, or by using such advanced techniques as SSRs and AFLP could well reveal polymorphism at the molecular level.     

Available nitrogen and arginine deaminase activity in groundnut (Arachis hypogaea L.) fields after imidacloprid, diazinon, and lindane treatments

Plant available nitrogen and arginine deaminase activities were determined in insecticide-treated groundnut (Arachis hypogaea L.) fields between July and November for three consecutive years (1997-1999). Diazinon was applied for both seed and soil treatments. However, imidacloprid and lindane were used only for the seed treatments. An average half-life (t(1/2)) of diazinon in seed- and soil-treated fields was 29.32 and 34.87 days, respectively. Its residues were detected till 60 days in both seed- and soil-treated fields. Diazinon treatments had shown stimulatory effects on available nitrogen in both types of treatments. However, the increase in arginine deaminase activity was only observed in diazinon soil-treated field. Residues of imidacloprid and lindane were detected in seed-treated fields till 90 and 120 days with an average half-life (t(1/2)) of 40.96 and 53.39 days, respectively. Imidacloprid had stimulatory effects, and lindane had adverse effects on both available nitrogen and arginine deaminase activities.     

Variation in a wild groundnut species, Arachis duranensis Krapov. & W.C. Gregory

Forty-two accessions of Arachis duranensis, a wild groundnut species that has been reported as a source of resistance to several groundnut diseases, were studied for 30 quantitative traits including total protein content, oil content, and reaction to groundnut rust. Protein profiles were also investigated for variation at the molecular level. Principal component analysis was applied to 28 traits that showed significant variation. Of these, only five characters, namely, height of the main stem, length of apical leaflet on the main stem, length of isthmus between pods, width of seed, and reaction to groundnut rust, accounted for more than 61.4% of the total variation. Protein profiles of these accessions were broadly similar, except some accessions which differed in few bands. The importance of these variations in strategies for germplasm collection and breeding is discussed.Submitted as Journal Article No. 1507 by the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Patancheru P.O. 502 324 A.P. India.     

花生二氢黄酮醇还原酶基因(DFR)的克隆及表达分析

二氢黄酮醇还原酶(dihydroflavonol 4-reductase,DFR)是植物花青素合成过程中的关键酶,催化二氢黄酮醇生成无色花青素。本研究利用花生(Arachis hypogae a L.)未成熟种子cDNA文库,通过大规模EST测序,从花生中克隆了DFR基因的全长cDNA序列。序列分析表明,花生DFR蛋白氨基酸序列与其他植物来源的DFR有很高的同源性。利用花生cDNA芯片和半定量RT-PCR方法对花生DFR基因表达模式的研究发现,DFR基因在果针中表达水平最高,其次是花,在根和叶中有微量表达;不同种皮颜色花生品种的种子中表达差异明显,随种皮颜色的加深,DFR基因表达增强,在中花9号黑色种子中表达量最高。对茎叶紫色花生种质材料的研究表明,在紫色组织中DFR基因表达较强。结果表明DFR表达量与花青素积累量呈正相关,说明DFR催化反应是花青素合成途径的关键步骤。     

晋西黄土区幼龄苹果+花生间作地土壤水分的时空分布特征

选取晋西黄土区具有典型代表性的幼龄苹果(Malus pumila)+花生(Arachis hypogaea)间作地作为研究对象,在花生生长季的不同时间对苹果+花生间作地和对照花生单作地的土壤水分进行定位监测,研究苹果+花生间作系统间作界面上土壤水分的时空分布特征和水分效应,及其对花生生长状况和产量的影响。结果表明:1)间作地土壤平均水分含量生长季逐月变化显著,水分耗用最大的时间为7月;2)在垂直方向上,土壤含水量随着土壤深度的增加而增加,在水平方向上,土壤含水量最低值出现在距离果树行最近的区域,并随着与树行距离的增加而增加;3)间作地种间土壤水分耗用量最大的区域为靠近苹果树的表层土壤;4)在当前树龄下,苹果+花生间作系统相对于花生单作土壤水分在整体上表现为负效应,对花生的产量产生了不利的影响,并限制了果农间作系统生态效益和经济效益的进一步提高。建议采取适当的调控和管理措施缓解种间水分竞争并提高花生的产量。     

Groundnut (Arachis hypogaea L.) improvement in sub-Saharan Africa: a review

Groundnut (Arachis hypogaea L.) is a multi-purpose legume crop widely cultivated in sub-Saharan Africa (SSA). However, yield levels of the crop has remained relatively low in SSA owing to a range of biotic, abiotic and socio-economic constraints. A dedicated groundnut improvement programme integrating new tools and methodologies to breed varieties suitable for current and emerging agro-ecologies and market needs is essential for enhanced and sustainable groundnut production in SSA. The objective of this review is to highlight breeding progress, opportunities and challenges on groundnut improvement with regard to cultivar development and deployment in SSA in order to guide future improvement of the crop. The review analysed the role of new tools in breeding such as, high-throughput and automated phenotyping techniques, rapid generation advancement, single seed descent approach, marker-assisted selection, genomic selection, next-generation sequencing, genetic engineering and genome editing for accelerated breeding and cultivar development of groundnut.     

Spermidine and flavonoid conjugates from peanut (Arachis hypogaea) flowers

A new spermidine triamide derivative has been isolated from peanut flowers and identified as N (1)-acetyl- N (5), N (10)-di- p-( EE)-coumaroylspermidine on the basis of detailed analysis of NMR, MS, and UV data. Two other spermidine conjugates, N (1), N (5), N (10)-tri- p-( EEE)-coumaroylspermidine and di- p-( EE)-coumaroylspermidine, as well as four flavonoid conjugates (quercetin-3-glucoside, quercetin-3-glucuronide, isorhamnetin-3-glucoside, and isorhamnetin-3-glucuronide) that have been previously reported in organs of other plants, have been found in this study in peanut ( Arachis hypogaea L.), a representative of the Leguminosae family, for the first time. The dynamics of photoisomerization in the spermidine conjugates have been investigated.     

花生油体蛋白家族基因的克隆和表达分析

油体蛋白是一类覆盖在油体表面的碱性小分子蛋白.油体蛋白的存在对于维护油体的稳定性非常重要,油体蛋白也是种子作为生物反应器表达重组外源蛋白的重要载体.本研究通过构建花生(A rac his hypogaea L.)未成熟种子的全长cDNA文库,测序得到284条编码油体蛋白的EST.根据编码蛋白分子量的大小可将花生油体蛋白基因分为6个亚族:AhOLE O- 16.9、AhOLEO- 17.7、AhOLEO- 18.6、AhOLEO-22、AhOLEO- 18.4和AhOLEO- 14.3 (GenBank登录号分别为:EG372527、EG373122、EG373716、EG372719、EE125019和EE124234),其中AhOLEO- 16.9,AhOLEO- 17.7和AhOLEO- 14.3分别有2个成员,其它家族的各只有1个成员.本研究首次从花生中克隆了分子较大的AhOLEO-22.cDNA芯片和半定量PCR结果表明6个亚族的油体蛋白基因在花生的不同器官和在种子不同发育时期表达模式相似,在根、茎、叶、花中几乎检测不到油体蛋白基因的表达,在种子中表达量高,在果针入土15d内几乎检测不到油体蛋白基因的表达,随着种子发育成熟油体蛋白基因的表达量逐步提高.本研究为研究花生油体蛋白基因的家族构成和利用花生油体蛋白基因提高花生含油量、生产外源蛋白等提供了有用的信息.     

On the diffusion constant of water in wheat

Diffusion-weighted magnetic resonance imaging (MRI) was used to obtain diffusion constants for water in the embryo and endosperm of wheat. Our experiments showed a significant difference between the diffusion constant for the two components. It was also shown that water diffusion in both the endosperm and embryo deviates from the typically observed Gaussian behavior in bulk fluids, showing a time-dependent diffusion constant. Diffusion constants for the embryo and endosperm were shown to differ by an order of magnitude. Using a model for restricted diffusion, information on the endosperm pore size and the embryo cell dimensions could be obtained.     

Genetic variation within and among species of genus Arachis, section Rhizomatosae

The genus Arachis is endemic to South America and comprises 80 species, 69 of which have already been described and eleven not yet published. The genus includes the cultivated peanut (A. hypogaea) and several forage species, the most important ones being A. glabrata and A. pintoi. Accessions of section Rhizomatosae, including three tetraploid species 2n = 4x = 40 (A. glabrata, A. pseudovillosa and A. nitida nom. nud.) and one diploid species 2n = 2x = 20 (A. burkartii), were evaluated using RAPD markers to assay genetic variability within and among species. The ten random primers used yielded a total of 113 polymorphic bands. The data were scored as the presence or absence of each band in each sample. A distance matrix and dendrogram were obtained using Link's coefficient and the neighbor-joining method. Most accessions analyzed grouped into two major clusters: the first comprised most accessions of A. glabrata and accessions of A. nitida, and the second cluster comprised accessions of A. burkartii. Arachis pseudovillosa and a few accessions of A. glabrata and A. nitida were placed between these major clusters. The diploid and tetraploid species were grouped quite separately, suggesting that the tetraploids did not originate from the diploid species analyzed.     

不同品种、外植体和光照条件对花生体细胞胚诱导的影响

用11个不同花生品种的胚轴为外植体，接种于含2，4－D的MS培养基进行体细胞胚的诱导。结果表明，不同的花生品种对花生体细胞胚的诱张每个外植体产生的体细胞胚的数目影响很大。此外还对不同外植体来源及不同的光照条件对花生体细胞胚诱导进行了研究。结果认为，成熟胚轴最适合于体细胞胚的诱志；不同品种最适合体细胞胚产生的光照条件不一样，汕油71要求在黑暗的条件下培养，泉花10号则要求有一定的光／暗比。     

我国花生根瘤菌技术应用与研究进展

花生根瘤菌技术应用与研究在我国已有30多年的历史,1949—1955年的资料已有总结。本文是总结1956—1985年的资料,30年来接种面积累积达3425.2万亩。1256次试验,增产5%以上的占试验总数90.9%;每亩增产花生10—35公斤的占试验总数81.8%。选育出一批优良菌株,其中以009、97-1和C₁菌株应用面积最大,达300万亩以上。菌剂生产有固体或液体培养,用草炭吸附,每克菌剂含活菌数1—2亿。接种技术普遍采用直接拌种,也有再用石膏等球化技术,一般球化比直接拌种增产。深施接种或幼苗接种也有增产效果。细沙壤土接种效果最好。接种后用地膜覆盖可获良好增产。亩施2—3公斤氮素不影响结瘤固氮,可提高花生产量。缺磷条件下增施磷肥,能提高接种效果。用钼酸铵和根瘤菌拌种可促进菌剂的增产作用。     

Release of soluble protein from peanut (Arachis hypogaea, Leguminosae) and its adsorption by activated charcoal

Peanut (Arachis hypogaea, Leguminosae) allergy is a major cause of food-induced anaphylaxis. The potential use of activated charcoal (AC) to adsorb and reduce the bioavailability of peanut protein allergens for use in the moderation of hypersensitivity reactions was investigated. The rate and extent of protein release from peanut and the adsorption of the solubilized protein by AC was determined under physiological pH values and confirmed in vivo using a porcine animal model system. Peanut proteins were adsorbed with equal efficiency at pH 2 and 7 and are completely removed from solution by an AC/protein ratio of approximately 80:1. This suggests that AC can bind protein under gastric (pH 2) or intestinal (pH 7) conditions. The rapid adsorption of soluble peanut allergens and the continuous binding of allergens released from peanut particulate material suggest the potential efficacy of using AC for gastric decontamination and possible elimination of a biphasic allergic reaction.