华北棉田二代棉铃虫发生程度中期预测   总被引：2，自引：0，他引：2  

王武刚  郭予元  戴小枫 《植物保护》1995,21(1):26-28

在华北棉区用扫网法和目测查虫法调查麦田一代棉铃虫幼虫发生量，用比较法和生命表分析法预测二代棉铃虫在棉田的发生程度和虫口密度。经1991—1994年应用检验，预测结果均与实际发生情况吻合。  相似文献   

美国优良牧草引种及其利用初探   总被引：1，自引：0，他引：1  

廖金才 《福建畜牧兽医》1996,18(4):9-11

本文论述从美国俄勒岗淋巴恩布莱格公司引进３６个优良牧草品种，并在福建省上杭县试种筛选的过程。探索在本地区栽培管理这批优良牧草技术及预测在我国南方利用发展前景。  相似文献   

The community idea in American country life     

Gene Wunderlich 《Agriculture and Human Values》2002,19(1):81-85

The American Country LifeAssociation was heir to Theodore Roosevelt'sCountry Life Commission, which examined thegeneral conditions of farming life in the opencountry, and...its larger problems. In1919, Kenyon Butterfield, a member ofRoosevelt's Commission, met withrepresentatives from 30 states and 25 nationalorganizations to form the American Country LifeAssociation. In that year, Butterfield, ACLA'sfirst president, published a book, TheFarmer and the New Day, whose defining chapterwas The Making of Communities: The CommunityIdea. The ACLA was educator created and led.Solutions to rural problems were seen aseducational matters. But educational philosophywas undergoing scrutiny and new educationalconcepts were arising from the bustling,industrializing, urbanizing times of late19th century. The experimental,unconstrained spirit of the nation at the turnof the century was formalized as pragmatism. Aleading pragmatist and educator of the time wasJohn Dewey, a contemporary of Butterfield.The communitarianism of Butterfield and Deweycarried throughout the life of ACLA in avariety of forms. Even after ACLA ended as anorganization in 1976, the concerns and idealscontinued in successor organizations, and canbe found in environmental, sustainableagriculture, and rural life organizationstoday. This paper traces one of continuingthemes of the ACLA, the community idea as a wayof adding a social dimension to agriculture'seconomic policies and development. The ACLAstory is a metaphor for country life throughmuch of 20th century America. ACLA is alsoa lesson in how organizations come into being,flourish, falter, die, and leave their legaciesto future generations.  相似文献   

美系獭兔的胴体性状和肉品质特性研究   总被引：4，自引：0，他引：4  

熊国远  朱秀柏 《中国畜牧兽医》2007,34(5):69-74

通过对20只美系獭兔屠宰性能和肉品质的测定，研究獭兔的生产性能和肉质特性及它们之间的关系，结果表明：美系獭兔5月龄的平均体重为2.533 kg,商用皮重0.410 kg,屠宰率为60.70%，右后腿重0.182 kg，体长和腰周长分别为30.69和18.04 cm；美系獭兔背最长肌和后腿肉的pH1(宰后1 h的pH)分别为6.42和6.43，pH24(宰后24 h的pH)分别为6.22和6.35,肉色L*值分别为54.66和52.67，a*值分别为12.37和9.89，b*值分别为9.06和4.08；兔肉的滴水损失、熟肉率、蒸煮损失、剪切力值、水分含量和肌内脂肪含量分别为2.06%、62.12%、30.44%、2.453 kg.f、73.60%和1.67%。商用皮重与热胴体重、体长存在极显著的正相关（P<0.01），与商用胴体重存在显著的正相关（P<0.05）。兔的体重（热胴体、商用胴〖JP2〗体、右后腿）、体型（体长和腰周长）与滴水损失、蒸煮损失呈负相关，与熟肉率、剪切力值呈正相关，但相关性都不显著（P>0.05）。  相似文献   

棉铃虫核型多角体病毒对宿主昆虫的弱化作用   总被引：12，自引：2，他引：10  

张忠信  孙修炼  张光裕 《植物保护学报》1998,25(3):204-208

棉铃虫核型多角体病毒（ＨａＮＰＶ）感染２龄幼虫,感染３ｄ,幼虫体长和体重明显小于对照幼虫。病毒感染４龄幼虫,残留活虫幼虫历期延长,但取食量减少３７．５２％。病毒感染５龄幼虫,感染幼虫蜕皮时间延迟１８ｈ,幼虫历期延长２ｄ。幼虫血淋巴蛋白电泳结果表明,幼虫蜕皮时间延迟主要原因是蜕皮过程延长。病毒感染５龄初幼虫,残留活虫蛹重减轻１４．１９％,成虫产卵量减少２０．５８％。结果表明,ＨａＮ－ＰＶ感染棉铃虫幼  相似文献   

胚轴切断法诱导棉花抗棉铃虫及其生化机制研究   总被引：1，自引：0，他引：1  

张青文  李萍  王刚  蔡青年 《植物保护学报》1998,25(3):209-212

诱导抗虫棉株对棉铃虫营养代谢功能的影响表明,胚轴切断法结合假单胞杆菌（Ｄ－２２５１）诱导处理的棉株可使棉铃虫相对生长率（ＲＧＲ）、相对取食量（ＲＣＲ）和近似消化率（ＡＤ）明显降低,分别降低２２．９５％、２６．１２％和２７．２３％,仅用胚轴切断法处理的棉株可使ＧＲＧ、ＲＣＲ和ＡＤ分别降低１７．２５％、２１．４４％和４．０９％。对诱导处理棉株体内植物多元酚和抗虫萜烯类的测定结果表明,经过胚轴切断法后,  相似文献   

齐墩螨素对棉铃虫毒杀作用特点及对常用杀虫剂毒力的影响   总被引：3，自引：0，他引：3  

王成菊  李学锋  吴学民  张文吉 《植物保护学报》1998,25(3):258-262

作者采用饲料混药法测定了齐墩螨素对不同龄期棉铃虫的毒力。结果表明,处理后４８ｈ和９６ｈ对初孵、１龄、３龄、４龄幼虫的致死中浓度ＬＣ５０分别为０．０１４１、０．０４９、０．５８、１．１４和０．００５、０．０２１、０．６４、１．１３μｇ／ｇ,同时还观察到１龄幼虫经处理９６ｈ后幼虫体长抑制率与药剂浓度成正相关,当药剂浓度为０．００６２５、０．０１２５、０．０２５和０．０５μｇ／ｇ时,体长抑制率分别为９．  相似文献   

Integrated management approaches for pink bollworm in the southwestern United States     

Thomas J. Henneberry  Steven E. Naranjo 《Integrated Pest Management Reviews》1998,3(1):31-52

The pink bollworm (PBW), Pectinophora gossypiella (Saunders) (Lepidoptera: Gelechiidae), is the key pest in cotton (Gossypium spp.) production areas in the southwestern United States and in many other cotton-producing areas of the world. The high costs of chemical control, continuing economic losses, secondary pest problems and environmental considerations suggest the need for ecologically oriented PBW management strategies. Extensive research has resulted in a broad array of monitoring, biological control, cultural, behavioural, genetic and host plant resistance methods that can serve as a base for the formulation of integrated PBW management systems. The life history characteristics of the PBW, in particular the high mobility of adults, indicate the need for combinations of selected integrated pest management (IPM) components implemented over large geographical areas. The areas involved present a wide range of PBW population densities, differences in cotton production methods and social and environmental considerations. The best option is tailor-made systems for targeted management areas with the selection of IPM components based on the PBW population density, crop production methods and economic feasibility. The unlikelihood of eradication indicates the need for long-term monitoring and programme maintenance following successful area-wide management. The success of area-wide PBW management is highly dependent on participation in the planning, site selection, implementation and assessment phases of the programme by all segments of the agricultural community. A highly effective extension--education communication programme is an essential component. Local uncoordinated efforts have not reduced the economic status of this pest in any area where it is an established pest. The potential long-term benefits of PBW population suppression on an area-wide basis appear to justify area-wide efforts in terms of reduced costs, more effective control, less environmental contamination and other peripheral problems associated with conventional control approaches.  相似文献   

后现代主义“反侦探小说”——以《芒博琼博》为例     

林元富 《福建农业大学学报(哲学社会科学版)》2008,(6):119-123

后现代“反侦探小说”是当代越来越受到评论家关注的一个亚文类。本文在简要梳理“反侦探小说”基本特征的基础上，结合非裔美国作家伊什梅尔·里德的代表作《芒博琼博》，从罪案之谜、侦探形象和叙事结构等方面进一步探讨后现代文本对传统侦探小说的解构。本文认为，对后现代“反侦探小说”政治性的认识，是一个值得商榷的问题。  相似文献   

美国黑人英语语言特征在电影对白中的表现及分析     

张勇 《四川畜牧兽医学院学报》2007,5(3):100-104

屡次被贴上“蹩足英语”标签的美国黑人英语（AAVE）在美国文化发展中所起的作用不容质疑，黑人英语作为黑人文化的源泉一直受到语言学家及社会学家的关注。文中围绕美国黑人英语中BE不变体、否定、嘲讽及黑人俚语运用等典型语言特征，以系列好莱坞经典黑人电影对白为素材，分析了美国黑人英语的“黑人味”。指出作为一种成熟的英语变体，美国黑人英语独特的语言体系及其蕴含的丰富黑人文化元素对研究美国多元文化的变迁具有重要意义。  相似文献