山下黑猪与鲁莱黑猪正反交F1代杂种优势的估计

旨在估计山下黑猪和鲁莱黑猪正反交F₁代杂种优势，筛选出合适的杂交方式，以提高优质肉猪的生产效率，满足人们对于优质猪肉的需求。本研究在山下黑猪（164头）和鲁莱黑猪（69头）及其正（6头山下黑猪♂×25头鲁莱黑猪♀）、反（3头鲁莱黑猪♂×35头山下黑猪♀）交4个群体中测定了生长肥育、体尺外貌（75～110 kg）、繁殖和胴体肉质（90～115 kg）4大类共43个性状，比较了这些性状在群体间的差异，并估计了正反交F₁代的杂种优势。结果表明，山下黑猪的生长肥育和体尺性状较好，鲁莱黑猪的繁殖和肉质性状较好，正反交群体介于它们之间。正交群体的繁殖性能优于反交群体，但生长肥育性能比反交差。由于这4个群体的母猪都是纯种，因此繁殖性状没有表现出明显杂种优势。除膘厚、胸椎数、45 min pH和剪切力无显著的杂种优劣势外，大部分胴体性状和肉质性状有明显的杂种劣势。生长肥育性状的杂种优势在正反交群体中的表现不一致，反交群体表现出显著杂种优势，而正交则无明显的杂种优势。本研究估计了山下黑猪和鲁莱黑猪正反交的杂种优势，为筛选山下黑猪和鲁莱黑猪的最佳杂交方式奠定基础。     

Screening of antagonistic Trichoderma strains and their application for controlling stalk rot in maize

Maize is one of the major crops in China, but maize stalk rot occurs nationwide and has become one of the major challenges in maize production in China. In order to find an environment-friendly and feasible technology to control this disease, a Trichoderma-based biocontrol agent was selected. Forty-eight strains with various inhibition activities to Fusarium graminearum, and Fusarium verticillioides were tested. A group of Trichoderma strains(DLY31, SG3403, DLY1303 and GDFS1009) were found to provide an inhibition rate to pathogen growth in vitro of over 70%. These strains also prevented pathogen infection over 65% and promoted the maize seedling growth for the main root in vivo by over 50%. Due to its advantage in antifungal activity against pathogens and promotion activity to maize, Trichoderma asperellum GDSF1009 was selected as the most promising strain of the biocontrol agent in the Trichoderma spectrum. Pot experiments showed that the Trichoderma agent at 2–3 g/pot could achieve the best control of seedling stalk rot and promotion of maize seedling growth. In the field experiments, 8–10 g/hole was able to achieve over 65% control to stalk rot, and yield increased by 2–11%. In the case of natural morbidity, the control efficiency ranged from 27.23 to 48.84%, and the rate of yield increase reached 11.70%, with a dosage of Trichoderma granules at 75 kg ha~(-1). Based on these results, we concluded that the Trichoderma agent is a promising biocontrol approach to stalk rot in maize.     

狂犬病病毒SRV9克隆株核蛋白基因的克隆、表达与特性分析

根据已发表的狂犬病病毒核蛋白基因序列，设计并合成了一对引物，从SAD株驯化的SRV9。蚀斑株中提取病毒RNA，通过RT-PCR扩增出核蛋白的全长cDNA序列，测序结果显示，其序列与国外报道的SAD母源株序列一致。将核蛋白的cDNA克隆至原核表达载体pET-28b( )中，转化大肠杆菌BL21（DE3）plyss，于30℃1mmol/LIPTG条件下诱导表达，大肠杆菌菌体裂解产物经SDS-PAGE分析，在分子量约为56kDa处出现一新的蛋白带。和预期的目的蛋白分子量相符，Western-blotting检测表明，表达产物能与狂犬病病毒阳性血清发生特异性反应，出现单一反应带，扫描分析显示，表达产物占菌体总蛋白的23%，包涵体分离，纯化后，纯度达89%，上述结果为核蛋白在狂犬病基因免疫和免疫检测中的进一步应用奠定了基础。     

MD病毒抗独特型抗体的研制

制备鸡马立克氏病病毒(MDV)抗独特型抗体(Ab2),探讨Ab2模拟抗原诱导免疫应答的能力.用MDV免疫SPF鸡,分离提纯鸡抗MD-IgG(Ab1),Ab1免疫BALB/C鼠,用鼠脾细胞与SP2/0细胞制备Ab2杂交瘤细胞株,间接ELISA筛选阳性杂交瘤细胞株,经克隆、纯化2×株抗MDV独特型抗体杂交瘤细胞株(6E5,7A12),其中6E5培养上清、腹水ELISA效价分别为4000×、10000×,免疫20 d攻毒,具有抗MDV感染保护.     

植物源农药的研究

植物源农药就其低毒、低残留、与环境和谐、对非靶标生物相对安全等优点,符合现代环保和人们健康的要求而越来越引起人们的高度重视。本文综述植物源农药的资源、植物源农药杀虫剂、杀菌剂和除草剂等的研究进展。     

春小麦新品种互麦14号栽培技术

介绍了我省育成的春小麦新品种—互麦14号的丰产栽培技术。     

一种适合稻区紫云英生产实际的紫云英加工调制方式

将紫云英鲜草分离为草汁、细渣、纤维状渣；以粉状能量精料为载体吸收汁液；3种制品都以晾晒的方式进行干燥。晾晒时，3种制品综合占场面积较原草减少近90％；3种制品均可在一个晴日内风干，比原草干燥速度提高一倍余；细渣品质与国标一级苜蓿草粉相当；“二次拌汁料”、“三次拌汁料”之粗蛋白、粗纤维含量符合生长肥育猪饲养标准；加工方式切合稻区紫云英生产实际及产区综合条件，有推广价值，且易推广。     

重组逆转录病毒载体的包装

将3.7kb的LacZ基因片段克隆到含标志基因Neo的逆转录病毒载体，pLXSN与pLNCX的多克隆位点，构建了含有LacZ基因的重组逆转录病毒载体pLLSN和pLNCL.在测定了G418对饥装细胞系PA317的最小致剂量后（最小致死剂量为0.3g/L），通过脂质体Lipofectin与磷酸钙2种介质，分别将2种重组逆转录病毒载体导入包装细胞系PA317进行包装，并以0.3g/L，的G418进行筛选，得到多个G418抗性克隆，经扩大培养，传代，分别得到包装pLLSN与pLNCL的2株阳性细胞，电镜下可见阳性细胞的培养上清中具有逆转录病毒形态特征的成熟病毒粒子，本0研究为运用逆转录病毒载体系统，解决转角因效率低的问题奠定了基础。     

JEV、PPV、PRRSV、PRV多联PCR的应用研究

用 JEV、PRRSV二联 PCR,PPV、PRV二联 PCR以及这 4种病毒 4联 PCR对来自内蒙、广州、广西、天津、北京、吉林病料进行检测 ,共检了 1 4 6份病料。其中 PRRSV阳性 7份 ,PPV阳性 1 2份 ,PRV阳性 2 1份 ,PRV和 PPV混合感染 4份。并对 5份人工接种 JEV小鼠病料检测 ,其中 4份为阳性。随后对部分阳性 PCR扩增产物进行点杂交和核苷酸测序鉴定 ,证实了 PCR扩增准确性。对内蒙 PRRSV阳性扩增带测序结果显示 ,我国流行 PRRSV为美洲型 ,在扩增片段的核苷酸序列上有 3个碱基差异     

EFFECT OF PARAQUAT ON MICROBIAL ACTIVITIES IN SOILS*

Summary. When paraquat was added to four different soils, nitrification was not appreciably affected but ammonification of soil organic-matter nitrogen was slightly retarded. Carbon dioxide evolution as well as oxygen consumption was used as an index of metabolic activity of soil micro-organisms and paraquat had a stimulatory effect at higher concentrations. Oxidation of added sulphur was slightly depressed. Paraquat decreased both the total mould and bacterial populations in Chehalis silt loam. After 30 days incubation the percentages of Streptomyces and Penicillia were markedly increased by most treatments but were little affected in Chehalis silt clay and Woodburn soils. Except for the temporary suppression of nitrification, paraquat had no significant influence on general microbial activities of importance to soil fertility. Some bimodal effects or toxicity inversions were observed with intermediate concentrations. Effet du paraquat sur les activités microbiennes dans les sols