抗虫基因及甜菜抗虫转基因研究现状

介绍了抗虫基因的种类、应用现状及甜菜抗虫转基因研究的现状，分析了目前培育抗虫转基因作物存在的问题和未来发展方向。     

甜菜抗虫转基因研究现状

介绍了作物转基因及其方法、国内外研究现状，综述了转基因技术在甜菜上的抗虫研究现状。     

抗虫绿豆晋绿7号对小鼠食用的安全性评价

为评价抗虫绿豆晋绿7号的食用安全性,对90只刚断乳昆明小鼠按性别和体重随机分为5组:空白对照组(BK)、对照组(CK)、低剂量组(JL)、中剂量组(JM)、和高剂量组(JH)。在60 d的实验中分别对小鼠体重、血液生化指标、脏器指数、脏器病理学及肝脏、肾脏凋亡相关基因检测。结果显示与对照组相比,晋绿7号绿豆对小鼠的生长发育未产生不良影响,对小鼠的血生化指标(除血清胆固醇和甘油三酯外)及器官发育均无显著影响;器官显微切片结构病理观察无明显异常病变;对小鼠肝脏、肾脏凋亡相关基因bax、bcl-2、Caspase-3和cyt-c进行RT_PCR检测,也未发现凋亡相关基因发生改变。表明抗虫绿豆晋绿7号在实验期内该剂量下对小鼠生长发育无不良影响,对小鼠血液生化指标及组织器官无毒性,对小鼠与感虫绿豆潍绿2117有等同的食用安全性。     

小黑杨转双价抗虫基因的研究

用根癌农杆菌介导的叶盘法,将蜘蛛杀虫肽与Bt基因C肽序列的融合基因导入小黑杨(Populussimonii×P.nigra),所获得的3株卡那霉素抗性再生植株进行PCR和PCR-Southern杂交检测的结果均为阳性,Southern杂交检测的结果2株为阳性.抗虫试验结果显示,3个转基因株系均具有明显的抗虫效果,能显著抑制舞毒蛾幼虫的生长发育,表现出强烈的抗虫作用.     

转抗虫基因烟草NC89纯合品系的获得及大田抗虫试验

经过连续三代抗虫性鉴定，选育出了表达直豆胰蛋白酶抑制剂（ＣＰＴＩ）的广谱抗虫转基因烟草ＮＣ８９纯合品系ＮＣ８９Ｌ２７－１９和ＮＣ９８Ｌ２７－２１。在大田对两个纯合系的抗虫性状进行了研究。①人工接种烟青虫；②害虫自然发生，不施杀虫剂；③在同一虫害防治阈值时施用杀虫剂。结果表明：转基因品系可稳定表达抗虫性状。在不施用杀虫剂时，田间相对抗虫效果在６４．７％～７０．５％之间；在施用杀剂时，可减少用药量４０％左右。转基因品系仍维持原ＮＣ８９主要植物学特性及农艺性状，为ＮＣ８９品种的抗虫改良品系。     

转双抗虫基因三倍体毛白杨抗虫性研究

用转双抗虫基因三倍体毛白杨不同抗虫株系通过室内群体和单体饲养舞毒蛾幼虫,定期观察并计算幼虫的累计死亡率,发育进度,体重,体长的变化.结果表明,转基因三倍体毛白杨对舞毒蛾幼虫有明显的致死作用,47号抗性最强,幼虫累计死亡率高达100%;11号、46号对舞毒蛾幼虫的致死率较高,累计死亡率均在90%以上.不同转基因株系对不同龄期幼虫致死作用不同,毒杀作用主要集中在1龄,其中46号株系对1龄幼虫的毒杀作用最强,幼虫死亡率达到84.8%.取食转基因株系的幼虫生长发育受到明显的抑制,其幼虫发育进度显著低于对照.用转基因株系饲养的单体幼虫取食量、体重、体长变化明显低于对照,且不同株系抗虫性存在差异,11号对2龄抑制作用最强,47号对3、4龄幼虫的抑制作用最强.     

抗虫转基因烟草8611纯合系的选育

对获得的表达江豆胰蛋白酶抑制剂的转基因８６１１进行了抗虫性研究，从转基因当代植株中筛选出两株高抗单株８６１１－６、８６１１－１１，在用其离体叶片饲养烟方虫８天后，对烟青虫的杀死率分别达到５０％和４０％。在田间接种及自然（不施药）条件下，８６１１－６、８６１１－１１子代植株的虫害指数分别为６３．５％、６９．３％（接种后１５天）和３７．７％、３９．８％（移栽后２５天），而未转基因对照植株的虫害指数分别为９３．５％和５７％。     

1999年中国家具市场研究综合报告

报告由意大利家具工业中心专业人士分析撰写,英文原版为120余页,译文略有压缩。内容丰富、资料详实,可参考性强,是企业产品市场定位、制订营销策略的重要参考依据。     

龙须菜挥发油的提取及抗菌抗虫活性研究

分别采用直接水蒸气蒸馏法和溶剂提取-水蒸气蒸馏法提取龙须菜(Gracilaria lemaneiformis)挥发油,并进行气相色谱-质谱法(GC-MS)分析和抗菌抗虫活性研究。结果显示:相比于直接水蒸气蒸馏法,溶剂提取-水蒸气蒸馏法提取的龙须菜挥发油中气味阈值较低的醛类成分相对含量低至0.20%,而营养保健价值高的羧酸及酯类含量达到21.54%。龙须菜挥发油对大肠杆菌O157(Escherichia coli O157)、金黄色葡萄球菌(Staphylococcus aureus)、沙门氏菌(Salmonella enterica)、单增李斯特菌(Listeria monocytogenes)和副溶血性弧菌(Vibrio parahemolyticus)5种常见致病菌均有一定的抗菌活性;溶剂提取-水蒸气蒸馏法和直接水蒸气蒸馏法提取的龙须菜挥发油对卤虫的半数致死量(LD50)分别为0.126,0.162mg/mL。     

1999年山东省夏季食品卫生抽检报告

本文报道了1999年山东省夏季食品卫生抽检结果。共抽查济南、青岛、泰安、济宁、枣庄、聊城、日照、临沂八市地流通及生产领域的冷食、茶叶、方便面、面粉、纯净水、保健食品等六类食品计208件(保健食品只检查包装标识)。结果表明,综合合格率为67.3％,内在卫生质量合格率为48.1％,包装标识合格率为68.3％;内在卫生质量全部合格的有茶叶、面粉,其他品种为方便面94.7％、冷食79.3％、纯净水76.5％;保健食品标识合格率为90.4％。对抽检结果进行了分析并提出了相应的建议。     

Internet环境下毛纺企业协同开发系统的设计

阐述了协同开发系统的概念,分析了该系统在毛纺加工中应用的意义和必要性,提出了系统的模型,建立了毛纺产品与工艺协同开发系统的总体框架、体系结构和运行模式.该系统可提高企业的工作效率,实现联盟企业之间的资源共享,降低产品的开发成本,增强企业的反应能力.     

Organotypic co-culture system to study plant extract bioactivity on hepatocytes

Natural plant extracts are complex mixtures of molecules that have to be uptaken and metabolized, at least by the intestinal barrier, before they reach their body targets. This paper evaluates the feasibility of using a co-culture system to assay the bioactivity of plant extract on hepatic cells closest to the in vivo situation. Caco-2 cells, mimicking intestinal barrier roles, were grown on inserts on a monolayer of HepG2 hepatocytes for 24 h. The co-culture induced some adaptations, but the Caco-2 cells showed no differences in their abilities to filter and metabolize grape-seed derived extract (GSPE) components. The co-culture clearly reproduced the ability of a procyanidin extract to decrease the triglyceride secretion of hepatocytes, a proven in vivo effect. This system mimics a human physiological system that is useful for assaying the bioactivity of extracts and may be able to be used for developing new functional foods.     

A collaborative study on the determination of tryptophan in feedingstuffs

The results are reported of collaborative work carried out at seven laboratories to assess the Miller^?1 and Buttery and Soar² procedures for the determination of tryptophan in soya bean, barley, groundnut, fish meal, a single cell protein and lysozyme. The results obtained by both methods were similar but the variation between laboratories was high and exaggerated by the variation in the recovery of tryptophan added before the hydrolysis stage. It was concluded that the determination of tryptophan in feedingstuffs is still a problem.     

A collaborative study on the determination of tryptophan in feedingstuffs

The results are reported of collaborative work carried out at eight laboratories to assess the Miller¹ and Spies and Chambers² procedures for the determination of tryptophan in protein concentrates and gave values for groundnut, soya bean and cottonseed meals of 1.0, 1.4 and 1.2 g/16 g N, respectively. The results obtained by both methods were similar, though collaborators preferred the Miller method.     

β-氨基丁酸诱导烟草抗碱初步研究

为探究外源BABA对提高烟草抵抗碱胁迫能力的机理。以云烟87为材料,从抗氧化系统,离子平衡和基因表达等方面来研究不同浓度BABA对碱胁迫下烟草幼苗的调节作用。结果表明:外源施加0.2mmol/L和0.5mmol/L BABA能促进碱胁迫下烟草幼苗根长和鲜重的增加;提高GSH、ASA、叶绿素和类胡萝卜素含量,降低脯氨酸和H₂O₂含量;增强超氧化物歧化酶、抗坏血酸还原酶、过氧化物酶和过氧化氢酶活性;降低烟草丙二醛含量和相对电导率来减轻碱胁迫对细胞膜损伤,提高有机酸含量缓解高pH毒害;降低Na+吸收,提高K+吸收来降低离子毒害。相对定量PCR表明:BABA可以诱导NtCaM和ABC转运蛋白家族基因表达来调节信号传导和物质转运;诱导GSH1和PROX1表达上调,促进GSH合成和脯氨酸代谢。以上结果表明:BABA诱导烟草抗碱是从抗氧化系统、有机酸合成、离子转运和基因表达等多方面综合作用的结果。      

氯化血红素诱导烟草抵御碱胁迫的初步研究

为研究外源氯化血红素（hemin）处理对碱胁迫下烟株生长和生理特性的影响,以云烟87为材料,从抗氧化系统、渗透调节系统、离子含量以及相关基因表达来探讨hemin对烟草抗碱的作用机理。结果表明:外源施加1 μmol/L hemin和2 μmol/L hemin能促进碱胁迫下烟株的生长;降低丙二醛（MDA）含量和相对电导率,提高超氧化物歧化酶（SOD）、过氧化物酶（POD）、过氧化氢酶（CAT）、抗坏血酸还原酶（APX）活力,同时增加叶绿素、脯氨酸、可溶性糖、可溶性蛋白等含量,提高根系活力;还可以减少烟株体内Na+积累,增加K+、Ca2+、Mg2+吸收。相对定量PCR结果表明,hemin处理后NtPDR1、NtPDR3、NtNAC和NtGSH1基因表达上调。综上所述,hemin缓解烟株碱胁迫伤害是激发抗氧化系统和渗透调节系统、加强离子转运及调节相关基因表达综合作用的结果。      

A collaborative study to validate novel field immunoassay kits for rapid mycotoxin detection

Kits designed to detect ochratoxin A (OA) and T-2 toxin by a membrane-based flow-through enzyme immunoassay were studied collaboratively by screening cereals (wheat, rye, maize and barley) for the presence of these mycotoxins. Sample preparation and test procedure were clearly described in the instruction leaflets included in the kits. A simple methanol-based extraction followed by filtration and dilution steps was prescribed. Reagents were successively pipetted to the membrane of the device, then colour development was evaluated visually. Limits of detection for the ochratoxin A and T-2 toxin tests were 4 and 50 microg kg(-1), respectively. Five laboratories took part in the first stage of this study, and five more joined the second stage. Cereal samples (blank, spiked or inoculated) were shipped with the kits to the participating laboratories, while results obtained were confirmed by high-performance liquid chromatography with fluorescence detection and by gas chromatography-mass spectrometry for ochratoxin A and T-2 toxin, respectively. Some initial difficulties were encountered. In the second stage, four ochratoxin A and four T-2 toxin kits were used by 10 collaborators to analyse 21 cereal samples. For the ochratoxin A kits, the percentage of false positive and false negative results were 2% and 4%, respectively. The results of one T-2 toxin kit were outliers and when excluded, the overall percentage false positive and false negative results were 6% and 3%, respectively.     

First report of strong phosphine resistance in stored grain insects in a far northern tropical region of Australia,combining conventional and genetic diagnostics

Although phosphine resistance monitoring and management programs are well advanced in Australia, the tropical northern part of the continent has received little attention. To address this, grain storages were sampled in the Townsville region in the Burdekin river catchment area of northern Queensland, and insect populations were subjected to resistance testing. Sampling of storages including silos, food processing facilities and feedlots was carried out during July to August 2019 and February to March 2020. Of the several species collected, populations of two major pest species, Rhyzopertha dominica and Tribolium castaneum were subjected to phenotypic resistance and molecular screening using discriminating doses and gene specific DNA marker, respectively. Utilising phenotypic assay, of the 17 populations of R. dominica, 12 were diagnosed as weakly resistant and five as strongly resistant; whereas of the 34 populations of T. castaneum, two were found to be susceptible to phosphine, 15 were determined as weakly resistant and 17 as strongly resistant. The molecular diagnostics, however, determined rph2 alleles for strong resistance in some populations each of R. dominica and T. castaneum that were diagnosed as weakly resistant in the phenotypic assay. The most prevalent rph2 alleles were found to be P49S and K142E in R. dominica populations and P45S and G131S in T. castaneum populations. Our results highlight the need of more comprehensive study towards determining the level of pests and resistance risks in this region.     

A collaborative study on the determination of available lysine in feeding stuffs

The methods of Carpenter¹ and Roach, Sanderson and Williams² for the determination of available lysine have been compared in two collaborative studies involving eight laboratories. The feeding stuffs used were: fish meal and groundnut meal in Trial 1 and soya bean meal, sunflower meal, a commercial mixed feed and wheat meal in Trial 2. There was no statistically significant difference between the two methods in terms of their overall means for any of the materials studied, though for mixed feed the values by Carpenter's method tended to be smaller. Inter-laboratory standard deviations for available lysine were generally greater by Carpenter's method, but significance was established only in the case of wheat. - Some of the problems encountered in both methods are discussed.