一株菊酯类农药降解菌的分离鉴定及其降解酶基因的克隆

摘要：【目的】筛选分离高效降解菊酯类农药的光合细菌,研究其降解特性,并对该菌株中降解酶基因进行克隆与初步分析。【方法】根据分离菌株的细胞形态结构、活细胞光吸收特征、生理生化特征及其16S rDNA序列系统发育分析鉴定降解菌,气相色谱法测定该菌株降解菊酯类农药的能力,PCR方法克隆降解酶基因。【结果】菌株PSB07-21属红假单胞菌属（Rhodopseudomonas sp.）,其降解最佳条件为3000 lx、35℃、pH 7,在此条件下培养15 d对600 mg/L甲氰菊酯、氯氰菊酯、联苯菊酯降解率分别为     

20种杀虫剂对柑橘矢尖蚧的室内毒力测定

柑橘矢尖蚧Unaspis yanonensis(Kuwana)是危害柑橘的重要害虫之一。为了筛选高毒有机磷农药的替代物,在室内条件下采用浸渍法分别测定20种杀虫剂原药对柑橘矢尖蚧1龄若虫的毒力。结果表明:供试杀虫剂对柑橘矢尖蚧的毒力大小依次为:甲氨基阿维菌素苯甲酸盐>阿维菌素>硝虫硫磷>噻嗪酮>杀扑磷>吡虫啉>乙酰甲胺磷>毒死蜱>喹硫磷>亚胺硫磷>稻丰散>敌百虫>残杀威>氟氯氰菊酯>甲氰菊酯>甲氧虫酰肼>苯氧威>高效氯氰菊酯>石硫合剂>矿物油。     

拟除虫菊酯类农药对茶树害虫的生物活性与残留降解

本文报道了溴氰菊酯、联苯菊酯、氯氰菊酯、顺式氯氰菊酯、杀灭菊酯、功夫菊酯和二氯苯醚菊酯等七种拟除虫菊酯类农药对茶树主要害虫的杀虫效果和在茶树叶片上的降解动态试验结果.上述七种拟除虫菊酯类农药对鳞翅目茶树害虫的幼虫都具有极高的毒力,但对其他害虫的活性谱则表现有差异.它们在茶树芽梢上的降解速率常数为0.20—0.28天^-1,在茶树上的半衰期为2.5—3.5天,明显较有机磷农药稳定.在影响降解的因素中,挥发、热分解、雨水淋洗的作用不大,由茶梢生长稀释所起的作用较为明显.鲜叶中的农药残留在加工过程中的降解率为15—45%,平均20%,远低于有机磷农药.成茶中的残留农药在泡茶过程中由于他们的低水溶性,因此浸出率很低,一般仅有1—4.5%.     

甘薯抗瘟种质创新与评价

通过常规杂交和杂种后代的抗瘟鉴定,创新和筛选出多份抗薯瘟材料。同时,对46份抗薯瘟病Ⅱ型菌系种质的主要性状进行鉴定和评价,表明泉薯148和American No．7二个抗瘟品种（系）兼具高产、高干（粉）和食用品质优等性状。     

人工环境鉴定小豆芽苗期耐冷性研究

对来自中国北京187份、天津33份、河北25份、山西16份、山东6份、河南1份、安徽1份、江苏22份、四川2份、陕西3份、辽宁18份、吉林33份、黑龙江5份,日本31份和韩国1份共384份小豆种质资源进行发芽期耐冷性鉴定,并以31份资源和18个品种为试验材料,进行三叶期耐冷性鉴定研究。结果表明：筛选出发芽期耐冷性较好（ 耐冷指数＞0.80）的资源31份;在三叶期低温8～5℃胁迫7d,资源G-I-34、JN95-0和E0064等表现出较强的耐冷性。采用三叶期低温8～5℃胁迫7d,只统计生长正常苗的方法进行小豆苗期耐冷性鉴定评价是可行的;小豆发芽期与三叶期耐冷性存在差异;苗期持续耐冷性存在差异。     

抗病高干甘薯地方资源的鉴定评价与育种利用

摘要：抗病高干甘薯地方资源的筛选是选育多抗、优质、高产甘薯新品种的基础。本文通过对收集的850份甘薯地方种资源进行抗病鉴定及品质分析：筛选出高干（干率≥30%）的资源材料71份,高干兼抗三病资源材料5份,高干兼抗两病资源材料23份,高干并抗一种病害的资源材料42份;通过对1981年以来育成的254个品种的亲本类型分析表明：85.8%的育成品种选用国内育成种（品系）作为亲本,18.5%的品种选用国外引进资源作为亲本,只有8.3%和0.78%的品种分别选用国内甘薯地方种和甘薯野生资源作为亲本。     

甘薯兼抗薯瘟病和蔓割病种质筛选鉴定

用甘薯瘟2个致病型菌株对557份甘薯品种(系)分菌系做盆苗和田间接种鉴定,并用蔓割病菌接种鉴定.结果表明,筛选出兼抗薯瘟病2个菌系的品种(系)31份,兼抗甘薯瘟和蔓割病的品种(系)有16份,其中泉薯860、泉薯854、金山93、榕选416、金山908、广薯88-70和泉薯853等7份与我省主栽抗病品种湘薯75-55(CK)相比,具有类似的双抗性能力,而其抗瘟能力更强.福薯87、林泗2号、金山57和湛93-16等4份对照品种只抗单个病害或兼抗单个菌系.     

中国裸燕麦β-葡聚糖含量的鉴定研究

对来源于中国13个省（区）1010份和国外引进的4份裸燕麦品种（系）进行了β-葡聚糖含量的鉴定研究。结果表明,中国裸燕麦β-葡聚糖含量为2．0％～7．5％,其中含量〈3．00％的占6．61％,3．00％～4．99％的占86．4％。5．00％～5．99％的占5．72％,≥6．00％的占1．18％。按品种类型划分,地方品种的含量低于育成品种（系）。按来源地划分,河北、山西、内蒙古的含量较高,云南、贵州、四川的含量较低,而陕西的含量最低。同年不同地点或相同地点不同年份种植的相同品种（系）,含量有一定的变化（0．27％～0．83％）。在鉴定中筛选出一批高β-葡聚糖品种（系）。本研究不仅为燕麦高β-葡聚糖育种提供了理论依据和物质基础,而且为降脂燕麦保健片的生产提供了优良品种。     

不同农药对木瓜秀粉蚧的毒力及复配增效作用

为筛选对入侵害虫木瓜秀粉蚧毒力较好的农药及复配增效配比,为该虫的化学药剂防治提供理论依据,本文采用叶面喷雾法测定了11种农药对木瓜秀粉蚧2龄若虫的室内毒力,挑选毒力较好的两种药剂进行复配,筛选增效配比,并进行田间药效试验。结果表明,11种农药对木瓜秀粉蚧的毒力大小依次为:螺螨酯>哒螨灵>噻虫胺>联苯菊酯>矿物油>高效氯氰菊酯>炔螨特>啶虫脒>吡虫啉>噻螨酮>四螨嗪。哒螨灵与螺螨酯(60∶40)复配共毒系数最大,为182.47。田间药效试验发现,混配药剂防效均高于单剂且达到差异显著。     

萝卜地方优良品种高制种潜力雄性不育系转育方法研究

不育系的制种潜力是决定制种产量的重要因素。在前期选育过程中对不育系制种潜力关注不够,往往导致所选育的品种制种产量低甚至无法制种,造成品种无法推广。我国拥有丰富的优良地方品种萝卜资源,但是存在着种质退化、栽培面积缩减、栽培区域小而分散的问题。培育杂交种是提升优良地方品种品质、维持栽培面积和扩大栽培地域的有效途径。本研究将Ogura胞质转育到26份优良地方品种萝卜资源,发现其中16份种质资源在Ogura胞质中的不育率达到或接近100%;建立了一种基于网纱隔离和壁蜂授粉的鉴定方法,用于分析这16份优良地方品种萝卜资源的保持系及其Ogura不育系的制种产量与潜力,发现练丝萝卜和五月红两份资源的不育系和保持系都具有较高的角果产量,有望转育成高制种潜力的不育系亲本,红灯笼、大青皮和心里美3份资源中都分离出具有较高种子产量的胞质雄性不育单株,但是其保持系种子产量很低,需要提高保持系的种子产量;小红袍水萝卜和扶沟萝卜的不育系和保持系的种子产量都处于中等水平,具有优化和应用的潜力;红水萝卜、青皮脆等5份资源不适合Ogura胞质不育系制种;狗头罐、绛县白、象牙白3份资源是自交不亲和材料。本研究发现,Ogura胞质的不同品种以及同一品种不同单株间制种产量差异巨大,说明从转育初代开始逐代监测和筛选制种潜力是非常必要的。本研究介绍一种简易高效鉴定及筛选萝卜胞质不育系制种潜力的方法,并用此方法初步筛选出一批高制种潜力的萝卜地方品种Ogura胞质雄性不育材料。     

Potentiation/Antagonism of pyrethroids with organophosphate insecticides in Bemisia tabaci (Homoptera: Aleyrodidae)

The binary mixtures of pyrethroids cypermethrin, alpha-cypermethrin, zeta-cypermethrin, bifenthrin, fenpropathrin, lambda-cyhalothrin, and deltamethrin plus organophosphates ethion, profenofos, chlorpyrifos, quinalphos, acephate, methamidophos, methyl parathion, and triazophos were evaluated on putatively resistant field populations of Bemisia tabaci (Gennadius) (Homoptera: Aleyrodidae) from Pakistan using a leaf-dip bioassay. Ethion exhibited good potentiation with all the pyrethroids. Quinalphos potentiated cypermethrin, fenpropathrin, and lambda-cyhalothrin but not bifenthrin. Acephate was potentiating with bifenthrin and fenpropathrin but antagonistic with zeta-cypermethrin. A potentiation effect was also found when methamidophos was mixed with bifenthrin and fenpropathrin. However, profenofos was antagonistic with cypermethrin, bifenthrin, and lambda-cyhalothrin. Similarly, bifenthrin + methyl parathion and deltamethrin + triazophos mixtures were antagonistic when tested on several populations of B. tabaci. Chlorpyrifos was antagonistic with cypermethrin but had an additive effect with fenpropathrin.     

Toxicity of seven foliar insecticides to four insect parasitoids attacking citrus and cotton pests

Laboratory studies were carried out to compare the toxicity of seven foliar insecticides to four species of adult beneficial insects representing two families of Hymenoptera: Aphelinidae (Aphytis melinus Debach, Eretmocerus eremicus Rose & Zolnerowich, and Encarsiaformosa Gahan) and Mymaridae (Gonatocerus ashmeadi Girault) that attack California red scale, Aonidiella aurantii (Maskell); sweetpotato whitefly, Bemisia tabaci (Gennadius) (both E. eremicus and E. formosa); and glassy-winged sharpshooter, Homalodisca vitripennis (Germar), respectively. Insecticides from four pesticide classes were evaluated using a petri dish bioassay technique across a range of concentrations to develop dosage-mortality regressions. Insecticides tested included acetamiprid (neonicotinoid); chlorpyrifos (organophosphate); bifenthrin, cyfluthrin, and fenpropathrin (pyrethroids); and buprofezin and pyriproxyfen (insect growth regulators [IGRs]). Chlorpyrifos was consistently the most toxic pesticide to all four species of beneficial insects tested based on LC50 values recorded 24 h posttreatment compared with 48-h LC50 values with the neonicotinoid and pyrethroids or 96 h with the IGRs. Among the three pyrethroids, fenpropathrin was usually less toxic (except similar toxicity to A. melinus) than was cyfluthrin, and it was normally less toxic (except similar toxicity with E. formosa) than was bifenthrin. Acetamiprid was generally less toxic than bifenthrin (except similar toxicity with G. ashmeadi). The IGRs buprofezin and pyriproxyfen were usually less toxic than the contact pesticides, but we did not test for possible impacts on female fecundity. For all seven pesticides tested, A. melinus was the most susceptible parasitoid of the four test species. The data presented here will provide pest managers with specific information on the compatibility of select insecticides with natural enemies attacking citrus and cotton, Gossypium hirsutum L., pests.     

贵州苦丁茶植物资源及化学成分分析

苦丁茶是我国南方各民族长期饮用的一类植物代用茶。在贵州,苦丁茶原植物有６科６属９种,主流品种为木樨科女贞属植物粗壮女贞〔Ｌｉｇｕｓｔｒｕｍｒｏｂｕｓｔｕｍ（Ｒｏｘｂ．）Ｂｌ．〕。分析了贵州５种苦丁茶植物叶的主要化学成分并和绿茶进行了对比,分析结果表明,苦丁茶类植物是一种营养成分含量丰富,不含咖啡因的营养保健的功能性饮料新资源     

Diversity Analysis of Chlorophyll,Flavonoid, Anthocyanin,and Nitrogen Balance Index of Tea Based on Dualex

The chemical compositions of tea (Camellia sinensis) are affected by numerous factors, such as cultivar, climate, leaf position, and cultivation pattern. However, under the same conditions, the chemical compositions are mainly determined by varieties. Therefore, we investigated the genetic diversity of chemical compositions of tea tree resources in China to screen excellent germplasm resources. Three chemical compositions index (including chlorophyll index, flavonoid index, and anthocyanin index) and the nitrogen balance index of tea leaves were measured in 102 tea germplasms planted in Chinese Tea Plants Improved Variety Germplasm Resources Nursery (CTPIVGRN) by Dualex on April 15 2019. Results showed that the chlorophyll, flavonoid, and anthocyanin contents and the nitrogen balance index significantly differed between the 102 tea germplasms. The genetic diversity index values were 2.005, 2.246, 1.599, and 1.838, and the average genetic diversity was 1.922. The 102 tea germplasms can be divided into four categories by cluster analysis under the genetic distance threshold of 11. These results suggest that the genetic diversity of tea germplasm resources in China is rich. This study’s results can serve as a basis for the diversified development and utilization of tea plant.     

广西部分地区野生茶树遗传关系EST-SSR标记分析

为了明确广西野生茶树种质资源的遗传背景,该研究从广西的宁明县、金秀县、苍梧县收集到14份地方野生茶树种质资源,以17个国家级茶树良种作为参照,采用EST-SSR分子标记技术,探讨了广西这三个地方野生茶树与国家级茶树良种间的亲缘关系以及广西地方茶树自身的遗传多样性。结果表明:15对EST-SSR引物共检测到68个等位基因,平均每个引物可扩增出4.53个,其中多态性位点为60个,多态性比率达88.2%。平均观测杂合度、平均期望杂合度、平均Shannon信息指数分别为0.42、0.55和0.97。PIC值在0.23~0.74之间,平均为0.52,多态性较好。遗传相似系数在0.53~0.9之间,平均值为0.71,31份供试材料在遗传相似系数为0.71分为5组群,76%参照品种聚在A组群,而广西本地的野生茶树资源则主要分布在B、C、D、E组群。利用该研究中的4对核心引物即可将31份供试材料全部区分开,挑选其中10个多态性较好的等位位点进行编码,构建31份供试种质的DNA分子指纹图谱。这表明广西野生茶树资源与国家级茶树良种间遗传差异较大、亲缘关系较远、遗传基础宽、多样性非常丰富,可作为茶树育种的亲本或开展茶树功能基因研究的材料。     

Monitoring and Risk Assessment of Pesticide Residues in Tea Samples from China

In the present study an effort was made to monitor the residue levels of 32 pesticides in tea samples collected from three representative tea districts of China during 2010 to 2012. A total of 223 samples of green tea, pu-erh tea, black tea, and oolong tea were determined using gas chromatography with mass spectrometry (GC-MS). Among 223 samples, 198 samples contained pesticide residues, and 39 samples had residue levels that were more than the European Union (EU) maximum residue limits (MRLs). The most positive and violated MLRs were observed in Oolong tea. The highest detection rates and the most often exceeding the MRLs were observed for the residues of bifenthrin. Ten pesticides were not found in the 223 tea samples. The potential health risks to consumers due to tea consumption in three representative cities were estimated. The results suggested that non-cancer hazards of organophosphorus, organochlorines, and pyrethroids and the cancer risks from exposure to hexachlorobenzene, heptachlor, chlordane, and pp’-DDT were clearly below the safe limit. Nevertheless, an investigation into continuous monitoring and tighter regulation of pesticide residues in tea samples are almost always desirable or even necessary for public health protection.     

Genetic base of tea (<Emphasis Type="Italic">Camellia sinensis</Emphasis> L.) cultivars in Sri Lanka as revealed by pedigree analysis

An understanding of genetic diversity and relationships among breeding materials is a prerequisite for crop improvement. Coefficient of parentage (COP) can be used to measure the genetic diversity among genotypes on the basis of pedigree information. In the present study, COP was estimated for 56 cultivars, including commercial tea cultivars developed by the Tea Research Institute of Sri Lanka and their parental lines. Mean COP of the 56 accessions studied was 0.097 and the value was raised up to 0.272 when non-related pair-wise comparisons were excluded. A single cultivar (Assam/Cambod introduction) was the nucleus of the commercial cultivars. Group mean COP of the cultivars derived from Assam/Cambod parentage was 0.17. Thirty-three percent of the pair-wise comparisons had 0.00 COP, highlighting that many cultivars were unrelated. Within the pedigree, 2 major COP clusters were identified: Assam/Cambod open-pollinated half-sib progenies, and full-sib progenies derived from crosses between Assam/Cambod and other parental lines. The elite groups within the pedigree, where Assam/Cambod parentage was concentrated, were also identified. Information generated in this study should be useful for effective utilization of available diversity in future breeding programmes as well as for proper conservation of genetic diversity in the adapted germplasm. This is the first report on estimates of genetic diversity based on COP in a woody perennial crop, such as tea.     

优质红碎茶资源的鉴定与筛选

我国生产的红碎茶在国际市场竞争力一直不强,缺乏适制红碎茶品种是原因之一.近年来,对原生起源中心云南茶区为主的120份茶树资源进行系统的发掘和鉴定,探明了我国适制红碎茶资源的基本情况,筛选出一批优异资源.加速这些资源的利用,将促进我国红碎茶品种的改良和红碎茶品质的提高.     

SCAR标记在茶树种质资源鉴定中的应用

SCAR标记是一种在RAPD技术的基础上发展起来的新型分子标记技术,提高了分子标记辅助选择育种的效率,在茶树种质资源的合理开发与利用中具有广阔的应用前景.运用优化后的RAPD反应体系对10个茶树品种的基因组DNA进行遗传差异分析,随机引物S89、S4分别在白毫早和福云6号中扩增得到长度为498 bp、1 622 bp的差异片段,命名为BHZ498、FY1622.根据它们的测序结果分别设计了一对特异引物,BHZ498的特异引物为SB1/SB2;FY1622的特异引物为SC1/SC2,用这两对特异引物对10个茶树品种的基因组DNA进行扩增.引物SB1/SB2和SC1/SC2分别在白毫早和福云6号中扩增出唯一的一条扩增带,而这两对引物在其他供试茶树材料中均无相应的扩增带,结果表明已将BHZ498、FY1622标记成功转化成SCAR标记.     

Occurrence and risk assessment of organophosphorus pesticide residues in Chinese tea

Tea is the second widely consumed beverage next to water. Tea drinking is one of the important pathways for human exposure of organonphosphorus pesticide. Consequently, incidence of organonphosphorus pesticide residues and risk assessment should be clear. In this study, the level of organonphosphorus pesticide residues in 810 Chinese teas manufactured between 2010–2013 was investigated using gas chromatography coupled with tandem mass spectrometry and a flame photometric detector. Incidence of organonphosphorus pesticide residues occurred with a frequency of 29% and the average concentration of 93 μg kg^?1. The residue levels varied from tea types, sale spots, and production area. Chlorpyrifos, isocarbophos, and triazophos were the only three organonphosphorus pesticides with detectable residues, and the detectable rates were 13.0%, 13.6%, and 17.4%, respectively. The corresponding average daily intake of chlorpyrifos, isocarbophos, and triazophos by tea drinking was 0.000083 μg kg^?1 bw day^?1, 0.0036 μg kg^?1 bw day^?1, and 0.0022 μg kg^?1 bw day^?1. These results showed that the total hazard quotient of organonphosphorus pesticide pesticides from tea drinking was less than 0.02 and that the tea-drinking originated organonphosphorus pesticide exposure had a little adverse health effect for human being.