Simple multiresidue method for monitoring of trimethoprim and sulfonamide residues in buffalo meat by high-performance liquid chromatography

A simple, specific, and rapid analytical method for the determination of trimethoprim (TMP) and three sulfonamide (SA) antimicrobial drug residues in buffalo meat is developed and validated. This method is based on a solid-phase extraction technique followed by high-performance liquid chromatography (HPLC)-photodiode array (PDA) detection. Target compounds were extracted from the meat by acetonitrile and water, cleaned up on a Bond Elute C 18 cartridge column, and separated on a RP-C 18 column during HPLC analysis. Acetonitrile along with water appears to be an excellent extractant as recovery of the analytes at maximum residues levels (MRLs) in spiked sample was in the range of 75-108%, with coefficient of variations (CVs) ranging between 1.34 and 22%. The limit of detection (LOD) and the limit of quantification (LOQ) were 0.031 and 0.062 microg/g, respectively, for all of the compounds. Intra- and interday assay precisions of the method at 0.125 microg/g concentrations for any drug ranged between 3 and 4%. The linearities of the TMP, sulfadimidine (SDM), sulfadoxine (SDO), and sulfamethoxazole (SMX) were 0.9989, 0.9999, 0.9998, and 0.9997, respectively. For robustness, the analytical method was applied to 122 buffalo meat samples obtained from export meat processing plants.     

洞庭湖湿地水生生物监测方法初步体系

介绍了微型生物群落监测法、指示生物法、污水生物系统、生物标志物等不同的湿地水生生物监测方法,并对未来的工作提出了展望。     

Global sources of pepper genetic resources against arthropods, nematodes and pathogens

Today India is the main producer of peppers especially the hot peppers, albeit mostly for domestic use. The thrips and mites, and the virus diseases transmitted by them along with fungal diseases like fruit rot, powdery mildew, bacterial wilt and leaf spots are the limiting factors in pepper productivity. The solution for managing these pests on a sustained basis exists in adopting eco-friendly approaches like using resistant cultivars. Fortunately huge natural genetic diversity exists in pepper and therefore, essential research efforts in finding out resistant sources and their utilization have been by and large dynamic and successful. Despite continuous scientific efforts there is a dire need for new cultivars with resistant traits for various pests suitable to varied climatic conditions, consumption and quality preferences all over the world. Efforts need to be intensified to find out useful genetic material and to introduce genes of resistance against insects, fungal and virus diseases into commercial cultivars. Genetic resources that have been used intensively in pepper breeding are for developing sweet peppers, hot peppers, bell peppers in various shapes, sizes and colors. Germplasm repositories at the World Vegetable Research Center (AVRDC) and United States Department of Agriculture (USDA) do possess number of genotypes resistant to insect pests, nematode, fungi, bacteria and virus diseases. At AVRDC resistant genotypes originating from several pepper growing countries to most virus diseases like Tobacco mosaic virus, Cucumber mosaic virus, Pepper veinal mottle virus, Chilli veinal mottle virus, Peanut bud necrosis virus etc., were identified from its rich pepper diversity. Exploitation of rich genetic diversity resulted in the development of new cultivars encompassing resistance to various pests and good agronomical traits. This has eventually resulted in meeting the demanding situations of diverse domestic as well as global production requirements. The chile database (Chile Database, 2010) highlights the exemplary utilization of germplasm and development of large number of cultivars and hybrids resistant to most diseases and nematodes around the world. This paper also depicts information on Indian sources of resistance to thrips, mites, leaf curl complex, nematodes and diseases, while presenting the scope for exploitation of diversity available in the Indian National Gene Bank and other repositories all over the world. An attempt is also made to identify the gaps in the genetic diversity and cultivars against the biotic constraints and the augmentation efforts required to be initiated toward enrichment of the gene pool for domestic as well as global use.     

利用信息技术改进林业技术专业地形图教学的实践

充分运用现代信息技术开展教学实践活动,有利于激发学生学习热情,实现最优化教学.福建林业职业技术学院教师在教学过程中,通过信息技术和多媒体演示,实现地形图三维动态演示教学,活跃了课堂气氛,激发了学生求知欲,在提高教学质量,建立新型师生关系等方面起到了良好作用.     

Identification of sugarcane grassy shoot-associated phytoplasma and one of its putative vectors in India

During a survey of sugarcane fields at the Sugarcane Research Institute, Shahjahanpur, Uttar Pradesh, India, in August–September 2012, 6% to 28% incidence of sugarcane grassy shoot disease was observed in different fields of sugarcane variety CoS 7250. The association of phytoplasma with symptomatic sugarcane was confirmed by direct and nested PCR amplification of phytoplasma ribosomal gene. Four different delphacid leafhopper species, viz. Cofana unimaculata Signoret, Exitianus indicus (Distant), Sogatella kolophon Kirkaldy and Hishimonus phycitis (Dist.) were the prevalent feeding species of the Auchenorrhyncha fauna in the symptomatic sugarcane fields. Out of these four leafhopper species, only E. indicus tested positive for phytoplasma presence. Phylogenetic analysis suggested that the phytoplasmas from sugarcane and E. indicus in the present study were members of 16Sr XI. The confirmation of association of sugarcane grassy shoot phytoplasma in E. indicus population is important to understand the secondary spread of this phytoplasma in sugarcane plants.     

Salt Stress Delayed Flowering and Reduced Reproductive Success of Chickpea (Cicer arietinum L.), A Response Associated with Na+ Accumulation in Leaves

Salinity is known to reduce chickpea yields in several regions of the world. Although ion toxicity associated with salinity leads to yield reductions in a number of other crops, its role in reducing yields in chickpea growing in saline soils is unclear. The purpose of this study was to (i) identify the phenological and yield parameters associated with salt stress tolerance and sensitivity in chickpea and (ii) identify any pattern of tissue ion accumulation that could relate to salt tolerance of chickpea exposed to saline soil in an outdoor pot experiment. Fourteen genotypes of chickpea (Cicer arietinum L.) were used to study yield parameters, of which eight were selected for ion analysis after being grown in soil treated with 0 and 80 mm NaCl. Salinity delayed flowering and the delay was greater in sensitive than tolerant genotypes under salt stress. Filled pod and seed numbers, but not seed size, were associated with seed yield in saline conditions, suggesting that salinity impaired reproductive success more in sensitive than tolerant lines. Of the various tissues measured for concentrations of Cl^?, Na⁺ and K⁺, higher seed yields in saline conditions were positively correlated with higher K⁺ concentration in seeds at the mid‐filling stage (R² = 0.55), a higher K⁺/Na⁺ ratio in the laminae of fully expanded young leaves (R² = 0.50), a lower Na⁺ concentration in old green leaves (R² = 0.50) and a higher Cl^? concentration in mature seeds. The delay in flowering was associated with higher concentrations of Na⁺ in the laminae of fully expanded young leaves (R² = 0.61) and old green leaves (R² = 0.51). We conclude that although none of the ions appeared to have any toxic effect, Na⁺ accumulation in leaves was associated with delayed flowering that in turn could have played a role in the lower reproductive success in the sensitive lines.     

关于促进畜牧业养殖小区发展的研究

我国畜牧业目前的分散饲养和粗放经营已经不适应动物疫病防控和食品卫生安全的要求,要加快畜牧业的现代化就必须推广农区的养殖小区建设。通过探讨解决养殖小区建设、规模养殖的财政支持和养殖用地等问题的途径,提出促进畜牧业养殖小区健康发展的相关政策建议。     

柏类绿化植物温室大棚扦插技术

柏类植物采用常规露地扦插繁殖,管理粗放,成活率低(一般为30%～40%),再加上柏类植物生长慢的特点,市场常供不应求,为此我院结合教学对各种柏类植物尝试了温室大棚扦插技术试验。从1999年开始试验,并不断地改进和完善。现在其扦插技术,成活率在98%以上。并且生长快,3～4年可长至     

近交对中国美利奴羊的影响及其克服和预测方法的研究

本文对中国美利奴羊(军垦型)应用多变量线性模型方法,分析近交对生产性能的影响,在各主要经济性状中,遗传力高的性状近交衰退较小,遗传力中等和低的性状近交衰退较大。选择能有效地克服近交的影响,对遗传力高的性状,加强选择克服近交衰退较强。采用指数选择克服近交衰退效果较好。利用双亲亲缘系数估测后代生产性能可早期预测近交衰退。     

矮败小麦胚芽鞘长度的研究

本研究对矮败小麦育性，株高和鞘长三性状相互间的遗传关系进行了分析。进一步证实了太谷核不育基因（Ｍｓ２）与矮秆基因（Ｒｈｔ１０）紧密连锁，同时发现矮败小麦的短芽鞘与矮秆性紧密相关，其短芽鞘特性可作为太谷核不育基因的早期形态标记。通过短芽鞘区分可育株与不育株的准确率因组合而异，平均为８８．２％。用２０ｍｇ．ｋｇ＾－＾１ＧＡ３浸种处理可明显促进可育株芽鞘伸长，但对不育株芽鞘伸长作用不明显，从而加大可育株