吉林省稻穗瘟药剂防治指标的初步研究     

吉林省稻瘟病预测技术研究协作组 《吉林农业大学学报》1992,14(3):4-8

文中确定了吉林省稻穗瘟病的经济损失允许水平:水稻黄熟期穗瘟发病率8～10％或穗瘟病情指数3～4。又根据吉林省有代表性的八个试验点五年的稻叶、穗瘟系统调查资料分析认为，决定吉林省生产中稻穗瘟最终病情的因素有三个:一是田间叶瘟基数;二是抽穗扬花期的气象条件;三是由当地生态栽培条件、水稻品种及稻瘟病菌生理小种群体共同决定的稻株抗病力。在此基础上提出吉林省稻穗瘟药剂防治指标。  相似文献   

Correlates of diet quality in the Quebec population     

Huot I  Paradis G  Receveur O  Ledoux M;Quebec Heart Health Demonstration Project Research Group 《Public health nutrition》2004,7(8):1009-1016

OBJECTIVE: To determine the correlates of a high-fat diet in urban, suburban and rural areas of Quebec, Canada. DESIGN: A secondary analysis of data collected as part of a 5-year multi-factorial, multi-setting, community-intervention project. SETTING: Urban, suburban and rural settings of the province of Quebec, 1997. SUBJECTS: Data were analysed from a sample of 5214 participants (2227 males, 2987 females). A food-frequency questionnaire was completed and a global index of food quality was calculated. Logistic regression was used to identify correlates of a diet high in total fats, saturated fat and cholesterol. RESULTS: In both genders, lower level of education, smoking status, French and English languages compared with other languages spoken at home, and a rural environment were associated with poor diet quality. Having no intention to eat low-fat dairy products more often was associated with a high-fat diet. In men, obesity (body mass index >/=30 kg m(-2)) and absence of reported health problems were correlates of a high-fat diet, while, in women, lower physical activity was a correlate. CONCLUSIONS: Future health interventions in Quebec should target people with low education, smokers and those living in a rural environment. Obese men and sedentary women should have access to specific dietetic resources.  相似文献   

Ri质粒转化牛膝及其发状根培养     

牛膝谭题组 《郑州牧业工程高等专科学校学报》1997,(4)

用发根农杆菌(Agrobacterium rhizogenes)的Ri质粒转化药用植物牛膝(Achyranthes bidentataBl.),诱导出了抗卡那霉素的发状根。将诱导的发状根进行固体平板培养和液体悬浮培养。在附加Km30mg/L的MS。和1/2MS。培养基上,发状根生长良好,而未经转化的对照组则死亡,表现出生长激素自主性。在附加外源激素IBA0.1mg/L和NAA0.1mg/L时。能促进发状根的成活、侧根的形成以及提高增殖倍数。表明适量的外源激素能促进发状根的生长。  相似文献   

蚯蚓粪中乳酸菌的分离及其在大肠杆菌O157：H7中的抗菌活性     

刘雪连  张宁  崔东良  王冲  孙振钧 《广西农业生物科学》2011,30(1):1-6

本研究利用SL培养基从蚯蚓粪中分离到54株具有产酸性能的菌株,并以E.coli O157：H7（EDL933株）作为指示菌株,采用点种法检测分离菌株的抑菌活性。结果表明其中6个菌株对指示菌具有拮抗作用,通过形态特征,结合16S rDNA序列分析,初步鉴定该6个菌株分别为食物魏斯特菌（Listeria welshimeri）、乳酸片球菌（Pediococcus acidilactici）、短乳杆菌（Lactobacillus brevis）和格氏乳球菌（Lactococcus garvieae）。分离到的乳酸菌对E.coli O157：H7（EDL933株）具有显著的抑制作用,发酵温度和初始pH值影响发酵液的抑菌作用,优化环境因子可以促进拮抗菌对E.coli O157：H7的抑制作用。本研究为进一步分离抗菌产物用于人畜共患病的预防和治疗提供了理论依据。  相似文献   

缸盖螺栓断裂原因分析     

杨永生  张雪花  仝建萍  刘书铎  马培红 《拖拉机与农用运输车》2011,38(4)

采用宏观、微观等观察手段对断裂的发动机缸盖螺栓进行分析。分析结果表明,缸盖螺栓断裂是由于氢脆延迟断裂而造成的。针对断裂原因分析了氢脆产生的原因并提出了预防措施。  相似文献   

Fire Environment Mechanism of Lightning-groundfire for Daxing''''anling Mountains     

WANG Mingyu SHU Lifu TIAN XiaoruiWildfire Group. Institute of Forest Ecology. Environment  Protection.Chinese Academy of Forestry. Beijing .P.R. Chinafire @prot. forestry. ac.cn 《中国林业科技(英文版)》2003,(1)

Ground fire is an igniting phenomenon that is difficult to control and lightning is the main cause of ground fire. The mechanism of lightning-ground fire is very complex. Daxing'anling Mountains forest region is the place that lighting-groundfire occurs more often and regularly. Our study on lightning-groundfire of this zone in 2002 shows: much more soil near the surface and the ground fuel is the matter preconditions of lightning-groundfire, and the weather conditions hasten the occurrence of lightning-groundfire. Especially in the conditions with low precipitation, long time drought, increasing surface temperature, relative humidity depressing and fuel dryness, lightning-groundfire is easy to occur. Lightning-groundfire has spatiotemporal character. Lightning-groundfire occurs mostly in primary forest zone, such as conifer forest, broadleaf forest, conifer and broadleaf mixed forest. Lightning-groundfire often burns slowly, for a long time and completely, and it has the characteristics of high conceal  相似文献   

天然林利用方式的变迁——中国天然林保护缘由分析之一     

中国社科院“天然林保护政策研究”课题组 《绿色中国(A版)》2001,(6):38-42

从天然林利用方式变迁的角度 ,分析了中国天然林保护的客观性与必然性。主要结论是 :森林利用所经历的食品———肥料———燃料———材料———原料———生态环境与生物多样性的变迁 ,是人类不断选择更为适宜的森林利用方式的结果。每个时期的森林利用方式都是人类根据当时自己掌握的知识、经验、技能和信息 ,作出的能使自己的利益最大化的选择。  相似文献   

胚胎移植受体黄牛的试验研究   总被引：2，自引：0，他引：2  

李国江  王成哲 《中国牛业科学》1997,23(4):26-28,31

试验期内共选择受体黄牛５９头，冻胚移植３３头，选择移植率达５５．５％，妊娠１１头，移植受胎率达３３．３％，分娩９头，妊娠产犊率达８１．８％，经过选牛实足和资料整理，从中得出几项有价值的数据。  相似文献   

福建省经济林协会赴台交流团赴台考察报告   总被引：2，自引：0，他引：2  

福建省经济林协会赴台交流团 《福建林业科技》2002,29(2):60-64

介绍了台湾林业资源概况、造林绿化与海岸林、森林生态保育、森林保护和治山防灾、森林游乐与生态教育、林业教育与试验研究以及台湾农会作用与应对WTO的一些策略 ,并提出观感与建议。  相似文献   

塑料管光滑紊流公式初步分析   总被引：1，自引：0，他引：1  

马存奎  李永顺  牟日升  姜宏  吕宁江 《节水灌溉》1991,(2)

在水资源日益紧缺的情况下。喷灌、滴灌、低压管道输水地面灌(简称“管灌”)等节水灌溉新技术得到迅速发展。因此也推动了塑料管的应用。当前,因塑料管所用水力计算公式不同,对设计和灌溉质量的影响已引起重视。本所结合管灌、微灌研究课题,专门对其水力摩阻进行了测试研究。本文将以部分实测资料验证分析塑料管光滑紊流计算公式,以明确其适用范围,提高设计精度。  相似文献