Screening of endemic wild Vigna accessions for resistance to three bruchid species

Several bruchid species attack stored pulses including those belonging to Vigna species.Wild Vigna accessions offer a host of useful traits for improvement of their cultivated types and hence 42 endemic wild Vigna accessions from 13 species were screened against three cosmopolitan bruchid species viz., Callosobruchus maculatus (F.), C. chinensis L. and C. analis (F.). The accessions exhibited varied reactions to three bruchid species and were categorized based on two criteria-seed damage (SD) and susceptibility index (SI). Based on SD, IC251442 accession of V. umbellata was found highly resistant, whereas accessions of V. umbellata (IC251439, PRR 2007-2 and IC251440), V. vexillata (IC248326 and IC248343), V. trilobata (JAP10-5) and V. trineriva var. bournei (IC247407) were found resistant to C. maculatus. Likewise, the accessions of V. mungo var. mungo (IC251390, IC251385 and IC251387), V. vexillata (IC248326) and V. khandalensis (Kumur local) were found highly resistant, whereas the accessions V. umbellata (IC251440), V. mungo var. mungo (IC251397), V. vexillata (IC248343) and V. dalzelliana (IC247408) were found resistant to C. chinensis. Interestingly, none of the accessions was found either highly resistant/resistant to C. analis. Based on SI, several accessions (including those susceptible on the basis of SD) recorded lower SI (<0.05) and were found resistant. A few accessions namely, V. trinervia (JAP 10–51), V. trinervia var. bournei (IC247407), V. pilosa (IC210575, IC210580 and IC210576) and V. dalzelliana (IC203864) were found resistant/moderately resistant to C. chinensis and C. maculatus, whereas the same lines were found moderately susceptible/susceptible against C. analis. The remaining accessions were found to be susceptible/highly susceptible to all bruchid species tested. These resistant lines could be further subjected to biochemical as well as molecular analysis to identify the specific seed components imparting resistance to bruchids. Simultaneously, these may be deployed in introgression breeding to develop bruchid resistant superior cultivars.     

Seed coat tannins and bruchid resistance in stored cowpea seeds

Seeds of wild species and varieties of Vigna were screened for their tannins and α‐amylase inhibitor contents as defensive compounds against cowpea weevil. Seed coats contained condensed tannins that were positively correlated to their colour but not to their resistance against the insect. The α‐amylase inhibitors were present in different amount in cotyledons of all species analysed. Amongst the cultivated lines assayed, Vigna unguiculata TVu 2027, an accession identified as moderately resistant, was found to contain the higher amount of α‐amylase inhibitor. When wild species were considered, V luteola and V vexillata (two resistant species) showed the highest content of α‐amylase inhibitors. In addition, two cultivated accessions (Vita 7 and IT 84E‐1‐108) of cowpea seeds, both classified as susceptible accessions, showing a different degree of bruchid damage in storage, were also analysed. No α‐amylase inhibitory activity was found in cotyledons of undamaged Vita 7 seeds, while the seed coat tannin content was found to be 13 times higher in undamaged Vita 7 seeds than in IT 84E‐1‐108 infested seeds. These latter results support the hypothesis that seed coat tannins must also be considered in biochemical defence mechanisms, which can deter, poison or starve bruchid larvae that feed on cowpea seeds. Copyright © 2004 Society of Chemical Industry     

一种可用于皮革分析的蛋白质快速检测方法

本文针对常规蛋白质检测法分析速度慢、难以实现在线自动检测的缺陷，建立起了一种新颖、简便、快速的分析方法，实现了Lowry试剂－Folin试剂体系、双通道流路的蛋白质快速流动注射分光光度分析法。本文进行了方法精密度、线性回归、检测限等可行性参数的测定和干扰试验，并将该方法应用于皮革分析上。本方法测得的蛋白质含量与双缩脲法分析的结果较为一致。试验结果表明，本方法的线性好、分析速度快、精密度高、检测限低、节省人力物力，可应用于皮革分析检验，为皮革工业的科研和生产提供可靠的依据。     

A non-impedimetric electrical method for detecting and enumerating micro-organisms

A non-impedimetric electrical technique is desribed which enabled the rapid detection and enumeration of micro-organisms during growth. Five bacterial strains demonstrated a linear response over a wide dilution range when calibrated against traditional methods. The growth of a wide range of organisms was detected using this technique.     

Combining parasitoids and plant resistance for the control of the bruchid Acanthoscelides obtectus in stored beans

Acanthoscelides obtectus (Say) and Zabrotes subfasciatus (Boheman) are the main bruchid pests of stored beans in widespread regions of Latin America and Africa. Host-plant resistance based on the protein arcelin is effective in reducing damage caused by Z. subfasciatus, but beans containing arcelin remain susceptible to A. obtectus. The compatibility of combining arcelin resistance with biological control by Dinarmus basalis (Rondani) was investigated in climatic chambers. Three arcelin containing bean varieties with high and intermediate resistance towards Z. subfasciatus (RAZ 36, RAZ 94 and RAZ 104) and an arcelin-free standard (Calima, susceptible to both bruchids) were investigated. Immature development of A. obtectus in arcelin-containing beans was prolonged by 15% as compared to the standard, allowing D. basalis to have access to suitable host stages for a longer period of time. Over a 20-week storage period, the combined use of resistant host plants and biological control agents yielded best results with the host-plant varieties RAZ 94 and RAZ 104. In both varieties, parasitoids managed to keep bruchid damage below 1% as compared to 4.7% in the arcelin-free standard, and bruchids were eradicated in 80% of the replicates. Control levels in RAZ 36, the bean variety with the highest resistance to Z. subfasciatus, were not greater than the standard. Our results show that the combination of certain arcelin-enriched bean varieties with the parasitoid D. basalis is favourable for suppressing damage by A. obtectus.     

谷氨酸生产中生物素含量的检测

微生物检测法是利用营养缺陷型菌株细胞的生长、繁殖与环境中某一限制性营养因子含量之间存在关联性而建立起来的一种生物检测方法.微生物法可以免去繁琐的样品预处理步骤,适合于生物素含量测定.在生物素浓度为0～0.8μg/L的范围内可以获得重复性较好的线性关系.利用该方法,分析了玉米浆、糖蜜、淀粉水解糖液中生物素的含量,分别为248.18μg/kg,1790.53μg/kg和1.25μg/L.     

A direct plate count method for detecting E. coli in frozen food by detecting indole in colonies

A medium giving maximum indole production colonies of Escherichia coli has been defined and includes diethylaminoethylcellulose which restricts the spread of indole through the agar medium. A reagent based on p-dimethylaminocinnamaldehyde has been developed to give optimum indication of indole production. A simple method which will identify E. coli in cultures obtained from selective media is described and an extension, including a resuscitation stage, devised for rapid and direct quantitation of E. coli from frozen foods.     

一种检测麦芽蛋白质溶解度的新方法

麦芽库值是反映大麦蛋白质溶解的重要指标,只有溶解适度的麦芽才能酿制出高品质的啤酒,因此麦芽蛋白质溶解度的检测尤为重要。EDTA是一种良好的金属离子螯合剂,本文分别用不同浓度的EDTA水溶液培养大麦,利用EDTA、金属离子和蛋白酶活性之间的关系,分析EDTA对蛋白酶活力和麦芽中各组分蛋白含量的影响、各蛋白组分之间的转化及其与麦芽库值的相关性,并以此为据建立检测麦芽蛋白质溶解度的新方法。      

微生物生长法检测生物素含量方法的研究

利用生物素营养缺陷型茵株的特点,建立了简便检测天然有机物中生物素含量的微生物方法。当生物素浓度在1～4μg／L,与平板生长圈直径大小呈直线相关。用此方法检测了玉米浆、酵母膏、甜菜糖蜜中生物素的含量分别为747,248,1707μg／kg。     

如何完善阿斯巴甜检验标准的检验方法

０前言阿斯巴甜,英文名为ＡＳＰＡＲＴＡＭＥ,化学名为天门冬酰苯丙氨酸甲酯简称ＡＰＭ,是当前用途较为广泛的食品添加剂。在食品中的使用功能为：增甜剂、糖类替代物、调味剂,甜度为糖的２００倍。阿斯巴甜为白色结晶性粉末,无异味,能溶解于水,微溶于酒精,无副作用,其水溶液在４０℃以上易分解而失去甜味。目前在食品加工行业主要用于软饮料如“可乐”等各种液体饮料、口香糖、咖啡、药用糖衣等,起调味与增甜作用,可作为较理想的蔗糖替代物,适合糖尿病患者食用。该产品起源于美国,我国起步较晚,于９０年代中期才开始,生…     

食用油中邻苯二甲酸酯类高通量检测方法的研究

建立固相萃取净化-气相色谱-质谱分析食用油中16种邻苯二甲酸酯的方法。样品用正己烷溶解,过SPE净化柱,采用气相色谱-质谱在选择离子检测(SIM)模式下进行定性、定量分析。结果表明:16种邻苯二甲酸酯在10～10 000μg/L范围内线性关系良好,平均加标回收率为70.0%～110.1%,相对标准偏差为2.68%～11.83%,检出限为10～15μg/L。     

Physical and biochemical bases of resistance in groundnut against bruchid,Caryedon serratus (Olivier)

A laboratory experiment was taken to study the “physical and biochemical basis of resistance in groundnut against bruchid, Caryedon serratus (Olivier)” at department of entomology, college of agriculture, svpua&t, Meerut during August 2018 to February 2019. Varietal screening of groundnut pods against bruchid were carried out with ten varieties and the performance of the varieties was assessed based on the physical and biochemical parameters. These varieties showed significant differences in the physical parameters selected for study such as pod length × width, pod shell thickness, test weight and inter granular space. Shell thickness contributed to resistance, while other parameters, pods size, test weight and inter granular space to susceptibility. Chemical parameters of those varieties showed significant differences for pod sugars, pod proteins, pod phenols and pod tannins. Pod sugars and pod proteins content had a positive effect on the development of the bruchid. While, pod tannins and pod phenols exerted a negative effect. Thus, resistance to groundnut bruchid is a multifaceted mechanism governed by both physical and chemical characters of pods.     

芝麻过敏原PCR检测方法

芝麻是重要的食品过敏原之一,微小剂量即可引起严重的过敏反应。针对芝麻过敏蛋白-2S白蛋白的基因序列设计PCR扩增引物,建立并优化芝麻过敏原检测的普通聚合酶链式反应(PCR)和实时荧光定量聚合酶链式反应(Real-time PCR)方法。结果表明,两种方法的最低检测限分别为0.1,0.01ng DNA,该方法特异性良好,成本较低,具有一定的应用价值。     

纯棉抗菌整理的简易测试方法

纯棉织物用抗菌卫生整理剂SCJ 963进行整理,可采用定性的抑菌圈法和定量的菌种培养计数法,对整理后织物的抗菌效果和耐久性进行测试。试验简要介绍了测试方法的操作及注意事项。     

针织物三维仿真新方法

介绍了使用OpenGL在Leaf-Glaskin模型基础之上建立了新的三维针织线圈模型,并将其作为模拟针织物的基础,进行针织物三维仿真的新方法,包括:线圈模型的建立、用OpenGL实现参数化模型和针织物的模拟效果。线圈模型的建立中包括模型结构和模型参数化。该方法解决了针织物在厚度方向的空间起伏问题,且可以模拟各种复杂针织物组织。     

A simple and effective method for detecting toxicity of chromium trioxide on Vicia faba

In modern biological research, there are many analytical methods to evaluate the toxicity caused by chemical agents, such as higher plant bioassay, flow cytometry, single-cell gel electrophoresis or the comet assay. However, these methods are either tediously experimental procedures or require a high-tech platform. In this study, the effects of chromium trioxide (CrO₃) on the primary root growth of Vicia faba seeds over 72 h were investigated. The primary root length of seeds cultivated in different concentrations of CrO₃ was collected and analyzed. It was indicated that the Vicia faba seeds maintained a good growing state when the CrO₃ concentration was below 100 μmol/L, while the root growth was suppressed when they were kept in 250 μmol/L of CrO₃ for 72 h or cultured with CrO₃ concentrations above 500 μmol/L. In comparison with the chromosome aberration bioassay, the primary root length assay is proved in this paper to be a simple and effective alternative for water toxicity testing in areas where heavy metal pollution has become serious.