谷子,黍,珍珠粟和玉米的根系比较研究     

中元明实  王德身 《杂粮作物》1991,(6):25-27

禾本科的杂谷类作物,基本是在同一栽培方式和生育过程中生长,而各作物一次根的形态特征、伸长方向及叶面积与一次根基部断面积的关系等,被看作是地上部和地下部的各种量的关系的体现。这些主要有关一次根的形态特征,对土壤中全部根系形态有很大的影响。至今未发现在田间定量地比较研究杂谷类作物根系的例子。在杂谷类中,对小作物(谷  相似文献   

Effects of dietary lipid levels on lipid deposition and activities of lipid metabolic enzymes in hybrid tilapia (Oreochromis niloticus × O. aureus)   总被引：1，自引：0，他引：1  

Han CY  Wen XB  Zheng QM  Li HB 《Journal of animal physiology and animal nutrition》2011,95(5):609-615

This study was designed to investigate the effects of dietary lipid levels on growth performance, lipid deposition and activities of lipid metabolic enzymes in hybrid tilapia (Oreochromis niloticus × O. aureus). Four isonitrogenous (300 g/kg crude protein) experimental diets containing graded levels of lipid (25, 55, 85 and 115 g/kg) were randomly assigned to triplicate groups of 180 juvenile fish. Fish were fed twice daily for 8 weeks. At the end of the experiment, the growth performance and proximate composition of fish were determined. The activities and gene expression of lipoprotein lipase (LPL) and hormone-sensitive lipase (HSL) were assessed as well. Fish fed the diets with 55 and 85 g/kg lipid had a significantly (p < 0.05) higher body weight gain than those fed the diets with 25 and 115 g/kg lipid. The whole-body and liver lipid contents were significantly (p < 0.05) elevated with increasing dietary lipid levels. Moreover, the activities and mRNA abundances of LPL and HSL in the liver, dorsal muscle and fat tissues were markedly altered by dietary lipid levels. Our data demonstrate a profound influence of dietary lipid levels on the growth and lipid deposition in hybrid tilapia, which is likely associated with the regulation of lipid metabolic enzymes including LPL and HSL.  相似文献   

Biofortification of soybean meal: immunological properties of the 27 kDa γ-zein     

Krishnan HB  Jang S  Kim WS  Kerley MS  Oliver MJ  Trick HN 《Journal of agricultural and food chemistry》2011,59(4):1223-1228

Legumes, including soybeans ( Glycine max ), are deficient in sulfur-containing amino acids, which are required for the optimal growth of monogastric animals. This deficiency can be overcome by expressing heterologous proteins rich in sulfur-containing amino acids in soybean seeds. A maize 27 kDa γ-zein, a cysteine-rich protein, has been successfully expressed in several crops including soybean, barley, and alfalfa with the intent to biofortify these crops for animal feed. Previous work has shown that the maize 27 kDa zein can withstand digestion by pepsin and elicit an immunogenic response in young pigs. By use of sera from patients who tested positive by ImmunoCAP assay for elevated IgE to maize proteins, specific IgE binding to the 27 kDa γ-zein is demonstrated. Bioinformatic analysis using the full-length and 80 amino acid sliding window FASTA searches identified significant sequence homology of the 27 kDa γ-zein with several known allergens. Immunoblot analysis using human serum that cross-reacts with maize seed proteins also revealed specific IgE-binding to the 27 kDa γ-zein in soybean seed protein extracts containing the 27 kDa zein. This study demonstrates for the first time the allergenicity potential of the 27 kDa γ-zein and the potential that this protein has to limit livestock performance when used in soybeans that serve as a biofortified feed supplement.  相似文献   

基于多周期相关的ECG信号压缩编码方法     

自兴发  从志坚  刘瑞明  孙坤 《西南大学学报(自然科学版)》2011,33(9)

提出了一种ECG信号压缩编码方案.该方案根据ECG信号类周期性的结构特征分割出信号周期,对一个周期进行提升小波变换,对生成的提升小波系数进行带截止区的均匀量化,再把量化系数分解成重要位置流、符号流、最高位位置流以及剩余比特流,然后对前3种数据流分别建立多周期相关的概率统计模型,进而实现自适应算术编码.实验数据结果表明:本方案在保证ECG信号压缩编码高效性的同时,比较好地实现了压缩编码的实时性.  相似文献   

高职院校畜牧兽医专业“大北农模式”创新人才培养方案的深化与推广     

高职院校畜牧兽医专业  大北农模式   创新人才培养方案的深化与推广 《畜牧与饲料科学》2020,41(5):120-123

乌兰察布职业学院畜牧兽医专业以提升人才培养质量为目的, 在“大北农模式”人才培养的基础上, 加强与企业的深层次合作, 将人才培养分为“基本技能—专业技能—综合能力”3个层次。通过不断改革人才培养方案、重构课程体系、优化课程内容、校企共建考核评价机制、专兼结合“双师型”教学团队的建立, 创建了具有特色的畜牧兽医专业人才培养模式, 形成“校企一体、产学并举、工学结合”的办学特点, 实现了“能养会繁、会繁能防、会防能治、会治能销、会销能管”的高技能人才培养目标。  相似文献   

棉花品种资源枯萎病抗性的研究   总被引：1，自引：0，他引：1  

罗家龙  夏武顺  吕金殿  吉冉中  吴 《中国农业科学》1980,(3)

加速棉花品种资源的抗病性鉴定,是当前选择杂交亲本开展抗病育种的迫切需要,也是培育抗病、丰产、优质新品种的主要物质基础。我国现保存的品种资源约3,675份,其中陆地棉3,044个,海岛棉289个,亚洲棉316个,非洲棉14个,野生棉12个。大量的品种资源过去均未作过系统的抗病性鉴定,因为缺乏快速准确的测定方法,仅依靠田间病圃进行鉴定,所以进展缓慢,数量有限。我国在开展棉花枯萎病菌生理型研究时,  相似文献   

烯效唑与稀土复配剂对黄瓜生长发育和产量的影响     

烯效唑与稀土复配剂对黄瓜生长发育和产量的影响 《勤云标准版测试》2006,(1)

在初花期喷施不同浓度的烯效唑和农用稀土复配剂,初步研究了复配剂对黄瓜生长发育和产量的影响,结果表明:复配剂可降低株高,延缓衰老;使结瓜期叶片中比叶重和叶绿素含量增加,光合速率增强;对黄瓜产量有显著的增产作用,以复配剂A3B2进行处理的效果最佳,增产幅度高达27.04%;促进增产的主要原因是提高了单瓜重,其次是单株结瓜数。  相似文献   

苗侗民族特色村寨旅游开发的利益分享机制建构研究     

——基于黔东南州的案例调查尹丽 《现代农业科技》2020,(21)

以黔东南州的苗侗民族特色旅游村寨为研究案例,立足于人类学、民族学的田野调查与跨文化比较研究的视野,深入考察这些村寨分布与旅游开发的现状,分析旅游开发的利益分享问题与原因,从以下四个方面提出苗侗民族特色村寨旅游开发中的利益分享机制：明确分享主/客体、成立第三方利益协调机构、多元化的利益分享方式、群众参与经营、参与决策、参与分配规则、确保公平与效率兼顾的利益分享效果。  相似文献   

液体培养在食用菌菌种提纯复壮上的应用     

卢才彪  胡中娥 《江西农业学报》1997,9(4):46-49

采用固体斜面培养和液体振荡培养活化后，比较保藏种、退化种、分离种在固体斜面上的萌发定殖、生长速度、菌丝长势等情况。结果表明，液体培养法是食用菌菌种提纯复壮的一条有效途径。  相似文献   

甘蔗野生近缘植物斑茅DNA转导创新育种材料研究初报   总被引：3，自引：0，他引：3  

曾慧  游建华  刘红坚  何为中 《广西农业科学》2002,(1):4-6

以甘蔗野生近缘植物斑茅（S.arundinaceum Retz）为外源DNA供体材料，栽培桂糖11号为受体材料，用“酚/SDS改良法”提取供体DNA，利用基因枪转导法把浓度为1ug/u1的供体DNA诱导入受体细胞并整合至受体染色体上获得表达。从再生植株中筛选获得3个与受体获得3个与受体在农艺性状表现有差异的转异再生杂种株系，并通过叶片过氧化物酶同工酶分析得以初步认定，这种人工种质新材料可供进一步育种研究。  相似文献