生物技术在畜牧业上的应用研究

从生物技术与畜禽品种、动物遗传育种,动物饲料资源开发,动物疫病的预防与诊断几个方面,论述了其在畜牧业中的应用,以期用生物技术来推动我国畜牧业的更快发展。     

转基因抗病毒病四倍体西瓜的培育

利用西瓜花叶病毒2号(WMV-2)外壳蛋白(CP)基因、小西葫芦黄花叶病毒(ZYMV)复制酶(NIb)基因和黄瓜花叶病毒(CMV)复制酶基因构建三价基因的植物表达载体,通过农杆菌介导转化四倍体西瓜植株,经分子检测证明目的基因成功地导入西瓜植株,并在后代中稳定遗传。经温室及大田接种鉴定,T3代转基因西瓜抗病毒性达中抗水平,为抗病毒无籽西瓜新品种的培育提供了可能性。     

Relating plant and pathogen development to optimise fungicide control of phoma stem canker (<Emphasis Type="Italic">Leptosphaeria maculans</Emphasis>) on winter oilseed rape (<Emphasis Type="Italic">Brassica</Emphasis><Emphasis Type="Italic">napus</Emphasis>)

In winter oilseed rape experiments at Rothamsted in 2000/01 to 2002/03 growing seasons, the severity of phoma stem canker epidemics in summer depended on the timing of phoma leaf spot epidemics in the previous autumn, and hence on the timing of Leptosphaeria maculans ascospore release. The first major release of L. maculans ascospores was earlier in 2000 (26 September) and 2001 (18 September) than in 2002 (21 October). Consequently, the autumn phoma leaf spot epidemic was also earlier in 2000 and 2001 than in 2002. The resulting stem canker epidemics were severe by harvest (July) in 2001 and 2002 but not in 2003. No correlation was found between the severity or duration of phoma leaf spotting (lesion days or lesion °C-days) and the subsequent severity of phoma stem canker epidemics. Rates of leaf production and loss were similar in the three growing seasons. Out of ca. 25 leaves produced on plants during each season, leaf numbers 10–14 generally remained on plants for the longest. Treatment with flusilazole + carbendazim in autumn decreased the severity of phoma leaf spotting for several weeks after treatment, decreased the severity of stem canker the following summer and increased yield significantly in 2001 and 2002 but not in 2003. The most effective timings for flusilazole + carbendazim application were when leaves 7–11 were present on most plants and at least 10% of plants were affected by phoma leaf spot. Two half-dose applications of fungicide reduced phoma stem canker and increased yield more than a single full dose application when phoma leaf spot epidemics were early (<800 °C-days after sowing).     

湖北和安徽省油菜病毒病调查和病毒血清鉴定

2003年秋至2005年春2个油菜生长季分别到湖北和安徽2省12县市油菜产区进行病毒病发病情况调查,除局部地区和地块发病率达到20%～40%,多数大面积油菜发病率在0.1%以下。应用间接酶联免疫吸附法检测258份病害样品,TuMV占样品总数的90.7%,CMV占样品总数的8.9%,ORMV占样品总数的0.8%。     

喷克防治苹果主要病害应用技术

喷克（ｍａｎｃｏｚｅｂ）８０％可湿性粉剂６００倍,８００倍,１０００倍室内对苹果轮纹（Ｐｈｙｓａｌｏｓｐｏｒａｐｉｒｉｃｏｌａ）抑菌效果均达１００％,６００倍,００倍对苹果斑点落叶病菌（Ａｌｔｅｒｎａｒｉａｍａｌｉ）炭疽病菌（Ｇｌｏｍｅｒｅｌｌａｃｉｎｇｕｌａｔａ）亦具显著的抑制效果,人工接菌条件下,８００倍液防治苹果斑点落叶病的实际保护期主１０－１２ｄ,防治苹果轮纹病的有效保护期为８－１０ｄ。田     

The Potential Benefits of Weeds with Reference to Small Holder Agriculture in Africa

Weed control is one of the most important crop protection activities undertaken in both intensive and low-input farming systems. However, even under intensive systems, crop protection which is less dependent on pesticides may require that weeds be managed to obtain a balance between crop and non-crop vegetation to encourage an increase in natural enemies of crop pests. In the low-input farming systems which sustain much of the rural population of Africa, weed control is usually done by hand and clean weeding is often beyond the labour resources of the farming family. The vegetational diversity of peasant agriculture in Africa to which weeds make their contribution, helps to decrease the risk of disease and pest epidemics. In addition to the pest control benefits of a diverse agroecosystem, weeds contribute to the resource base of the rural community, providing a source of secondary foods, medicines and insecticides. Weed control within an integrated crop protection system appropriate to the needs of the resource-poor farmer, requires that weeds are managed in such a way that their biodiversity is maintained and the more useful species retained within the field or field margin. Those weeds with high food potential or which have pesticidal or medicinal properties might be deliberately encouraged within the crop or field margins. Certain weed species may harbour important pests or diseases of local crops and therefore should be selectively removed. The paper reviews and discusses the literature on the beneficial and deleterious effects of weeds and argues for a weed management strategy which balances the effects of weed competition on crop production with the ethnobotanical and pest control attributes of individual weed species and weed communities.     

Associations among antimicrobial drug treatments and antimicrobial resistance of fecal Escherichia coli of swine on 34 farrow-to-finish farms in Ontario, Canada

Logistic regression was used to model associations between antimicrobial treatment and resistance among fecal Escherichia coli of finisher pigs at the farm level. Four sets of potential risk factors representing different levels of refinement of antimicrobial use on farms were modelled on resistance to antimicrobials. Final models for each antimicrobial were constructed from treatment and management variables significant on initial screening, and corrections for overdispersion were made. In general, in-feed antimicrobial treatment of pigs was more consistently associated with an increased risk of resistance than individual-animal treatment. Antimicrobial treatment in starter rations was significant in final models of resistance to ampicillin, carbadox, nitrofurantoin, sulfisoxizole, and tetracycline. Treatment in grower–finisher rations was significantly associated with resistance to ampicillin, spectinomycin, sulfisoxizole, and tetracycline. There was little evidence that in-feed antimicrobials increased the risk of resistance to gentamicin, which is a drug used only for individual-pig treatment in this study population. These results suggest that antimicrobial medication of rations of post-weaning pigs selects for and maintains antimicrobial resistance among E. coli of finisher pigs. Although resistance was common on farms that did not medicate rations of post-weaning pigs, the results indicate that antimicrobial use does increase the risk of resistance to the antimicrobials studied.     

新疆苜蓿病害种类和分布的初步研究

文章报道了新疆天山南北８个地州人工栽培紫花苜蓿上的１９种病害,其中一种病害,类似由黑白轮枝菌（Ｖｅｒｔｉｃｉｌｌｉｕｍａｌｂｏ－ａｔｒｕｍＲｅｉｎｋｅｒｅｔＢｅｒｔｈ．）引起的苜蓿黄萎病,而由束状匍柄霉（Ｓｔｅｍｐｈｙｌｉｕｍｓａｃｉｎｉ－ｉｆｏｒｕｍ（Ｃａｖ．）Ｗｉｔｓｈ．）引起的苜蓿匍柄霉叶斑病为新疆首次指导。不同地区苜蓿地的病原群体结构呈现较大差异。     

鲜切菊花栽培技术

近年来,菊花的种植面积和鲜切菊花的产量大幅增长,但菊花种植过程中病虫害较严重。为提高鲜切菊花的科学种植水平,从品种的选择、定植方式、栽培管理和病虫害防治4个方面分别介绍了春菊、夏菊、秋菊和寒菊的栽培技术要点,以期为提高鲜切菊花的观赏价值和经济效益提供有益参考。