延边工业企业技术进步及科技管理状况分析     

姜德荀  黄永春  温艳玲 《延边大学农学学报》1999,(3)

分析了延边工业企业技术进步及科技管理状况,提出了企业管理和科技管理中普遍存在的现象．  相似文献   

肉鸡血浆VLDL浓度的选择效应——对产蛋性能的影响     

龚道清  李辉  张德祥  杨山  王启贵  张军  王志跃  赵万里 《扬州大学学报(农业与生命科学版)》1999,(4)

以零世代和一世代高、低脂系肉鸡为素材 ,个体记录高、低脂系母鸡产蛋性能 ,屠宰测定零世代 54周龄母鸡腹脂重 (率 ) ,探讨肥度性状与产蛋性能的关系 ,并研究零世代、一世代高、低脂系产蛋性能选择效应。结果表明 :在限饲条件下 ,腹脂重 (率 )与开产日龄、产蛋量表型相关很弱。腹脂重 (率 )与蛋重呈负表型相关趋势 ;零世代高、低脂系产蛋性能差异不显著。一世代低脂系比高脂系早开产 6.7d,低脂系 4 0周龄和 54周龄产蛋量显著高于高脂系 ,表明对血浆 VLDL浓度的选择使产蛋性能产生了有益的间接反应  相似文献   

Tolerance to abiotic stresses in potato plants: a molecular approach     

Antonella Leone  Antonello Costa  Federica Consiglio  Immacolata Massarelli  Emilia Dragonetti  Monica De Palma  Stefania Grillo 《Potato Research》1999,42(2):333-351

  相似文献   

恒定磁场对小麦种子的生物物理机制研究   总被引：2，自引：0，他引：2  

杨林楠  陈德万 《西南大学学报(自然科学版)》1999,21(4):342-344

根据恒定磁场促进小麦种子三磷酸腺甙（ＡＴＰ）含量增加的作用,建立了线粒体在恒定磁场中的理论模型,并应用物理和生物化学的方法对模型进行了讨论,得出线粒体在恒定磁场下获得能量,得种子ＡＴＰ增加的根本原因。  相似文献   

腾格里沙漠东缘飞播固沙植物生长状况的研究     

田永祯  李埃新  庞德胜 《内蒙古林学院学报》1999,(2)

１９９２－ １９９４ 年连续３ 年对腾格里沙漠东缘飞播区飞播植物生长状况调查结果表明：籽蒿在不同立地条件下生长状况差异很大,迎风坡生长最好,覆沙地次之,丘间地最差。在不同年份籽蒿生长状况主要受降水量的影响;三种固沙植物的生物量,沙拐枣最高为１９１．４ｇ 株－ １－ １,籽蒿次之为１８６．１ｇ 株－ １年－ １,花棒最少为５９．９ｇ株－ １－ １。  相似文献   

运用致病毒素筛选抗烟草黑胫病细胞突变体I抗毒素愈伤组织的有效筛选   总被引：1，自引：0，他引：1  

王荔  罗文富  杨艳琼  杨德 《云南农业大学学报(自然科学版)》1999,(1)

以６０Ｃｏ－γ射线照射烟草优质感病品种的花药作为诱变手段,用烟草黑胫病疫霉菌粗毒素为筛选剂,对烟草花粉植株叶片的愈伤组织,进行抗病突变体细胞的筛选．试验表明：毒素对烟草愈伤组织的存活和增殖有明显的抑制作用,抑制程度随毒素浓度提高而加强,同一浓度对不同品种也存在着差异．综合毒素浓度对烟草愈伤组织抑制、增殖程度及筛选的有效性,初步认为：筛选红大和Ｋ３２６抗黑胫病突变体细胞的最适粗毒素浓度分别为３０％和４５％．所筛选出的抗病突变体细胞,其细胞水平的抗性与再生植株的抗病性鉴定相吻合．  相似文献   

不同激素浓度及培养基对烟草愈伤组织分化的影响   总被引：8，自引：3，他引：5  

王荔  杨艳琼 《云南农业大学学报(自然科学版)》1999,14(4):371-375

 以烟草愈伤组织为材料,研究不同激素浓度配比、不同培养基对愈伤组织绿苗分化的影响,试验结果表明,在MS+IAA0.5mg/L+KT2.0mg/L培养基上可获得较高的绿苗分化率,在分化培养基中,除必需的大量元素外,一些有机物质,维生素及微量元素也对烟草愈伤组织的分化起重要作用。  相似文献   

Factors influencing adoption of soil and water conservation measures in southern Mali     

F. Bodnr  J. De Graaff 《Land Degradation \u0026amp; Development》2003,14(6):515-525

A soil and water conservation (SWC) extension programme, promoting erosion control measures and soil fertility measures, has been going on in southern Mali since 1986. Five factors that influence farmer adoption of SWC measures were analysed: land pressure, cotton‐growing area, possession of ploughing equipment, possession of a donkey cart and farmer training in SWC. Interviews were carried out with 298 farmers and two to three fields per farmer were visited, in 30 representative villages and 30 villages with high SWC adoption. Correlation, regression and factor analysis led to the following conclusions:

• (1) Farmers in the high land‐pressure area adopt more soil fertility measures.
• (2) Farmers in the cotton‐growing area adopt less SWC measures.
• (3) Farmers with more ploughing equipment adopt more SWC measures.
• (4) Farmers with a donkey cart adopt more soil fertility measures.
• (5) Trained farmers adopt more erosion control measures.

There is a strong correlation between the adoption of erosion control measures and soil fertility measures that could not be explained by these five factors only. This suggests that there are additional factors that trigger the adoption of SWC measures. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   

Karyotype analysis of interspecific hybrids between Haliotis rufescens and Haliotis discus HANNAI     

Gabriel Amar‐Basulto  Fabiola Lafarga‐De la Cruz  Patricia Iturra‐Constant  Cristian Gallardo‐Escárate 《Aquaculture Research》2011,42(10):1460-1466

Evidence of hybridization in Haliotis has been mainly supported by hatchery experiences and collection of wild hybrid abalones among several species from natural populations worldwide. However, despite the importance to understand the role of the hybridization process through Haliotidae evolution, and also its impact on the abalone aquaculture, genetic studies in hybrid abalones have been poorly developed. Herein, cytogenetic approach allows studying the genetic conformation in hybrid organisms at the chromosome level. This paper reports a quantitative karyotype analysis in Haliotis rufescens, Haliotis discus hannai and their interspecific hybrid. Thus, to characterize chromosome pairs and establish cytogenetic comparisons, chromosome banding with distamycin‐A/4,6‐diamidino‐2‐phenylindole fluorochromes and morphologic measurements were performed. The results showed that the hybrids are successfully viable and their karyotypes evidenced a conservative chromosome number of 2n=36. The karyo‐idiogram showed a high correspondence in chromosome pair morphology among the hybrids and their parental species, except for a single heteromorphic pair that corresponds to the chromosome 16 from H. rufescens andH. d. hannai respectively. The implications of the abalone hybrid viability derived from its chromosome composition are discussed.  相似文献   

Homeopathic complex increases survival without affecting the performance of Nile tilapia during masculinization     

José Dias-Neto  Gustavo Moraes Ramos Valladão  Pedro Henrique De Oliveira Viadanna 《Journal Of Applied Aquaculture》2017,29(1):33-45

During the masculinization of Nile tilapia, Oreochromis niloticus, the effect of a homeopathic complex (containing Chamomilla, Quina, and sulphur) was evaluated based on survival, performance, gills and liver integrity, and parasitism. Group fed with basal diet + 17 alpha-methyltestosterone (control) showed low survival (40.02%), while the group that additionally received homeopathy and the group that received sucrose (vehicle) showed 73.7% and 87.7% survival, respectively. The growth performance of the group that received homeopathic and the control group was significantly higher than that of the group that received only sucrose. Still, fish that received the homeopathic complex showed higher branchial and hepatic integrity as compared to the other groups. The homeopathic complex contributes to a greater survival of fish in addition to maintaining satisfactory growth. Furthermore, homeopathy contributes to the improvement in gill and liver integrity of the Nile tilapia larvae.  相似文献