极多产对冷胁迫后黄瓜幼苗恢复生长的影响     

吕晓菡  寿森炎  廖芳宾 《北方园艺》2007,(8):3-6

以黄瓜(Cucumis sativus L.)幼苗为试材,研究了不同浓度极多产溶液(壳聚糖的酸性溶液)的处理对其低温胁迫后的生长势和生理生化特性变化的影响.结果表明:在低温胁迫后恢复生长过程中,极多产处理浓度为100mg/L和200mg/L的黄瓜幼苗恢复生长较快,常温下恢复生长15d幼苗的光曲线净光合速率及活性氧清除酶SOD、APX和POD也明显高于对照,同时植株的株高、最大叶面积、鲜重和干重也都显著高于对照.说明适宜浓度的极多产处理能有效地促进冷胁迫后黄瓜幼苗的生长,对低温胁迫有一定的缓解效应.  相似文献   

沙生牧草和盐生牧草抗氧化特性比较   总被引：1，自引：0，他引：1  

李志刚  张玉霞  董丽杰 《中国草地学报》2007,29(5):115-118

试验以在科尔沁沙地和盐碱地生长的羊草、芦苇、苔草、扁蓿豆四种多年生牧草为材料,检测其膜质过氧化程度和抗氧化酶活性。结果表明,盐碱地生境对四种牧草的伤害较沙地严重,四种牧草对两种逆境的适应表现是芦苇>羊草>苔草>扁蓿豆。由抗氧化酶活性测定可知,沙生牧草主要通过增强POD酶活性,盐生牧草主要通过增强SOD和CAT酶活性提高其抗氧化能力,四种牧草的抗氧化酶活性之间有明显的差异。  相似文献   

Restoration and stress relief through physical activities in forests and parks   总被引：2，自引：0，他引：2  

Ralf Hansmann  Stella-Maria Hug  Klaus Seeland 《Urban Forestry & Urban Greening》2007,6(4):213-225

A field survey assessed the restorative effects of visiting an urban forest and a city park in Zurich, Switzerland. Respondents rated their headaches, level of stress, and how balanced they felt both prior to visiting the outdoor location and at the time of being interviewed. Suffering from headaches and stress decreased significantly, and feeling well-balanced increased significantly. The recovery ratio for stress was 87%, and the reduction in headaches was 52%, in terms of the possible improvements on five-point rating scales. With respect to feeling well-balanced, the observed changes amounted to 40% of the possible enhancement. Positive effects increased with length of visit, and individuals practising sports (e.g., jogging, biking, playing ball) showed significantly higher improvements than those engaged in less strenuous activities (e.g., taking a walk or relaxing). These findings support previous research on how exercise in green spaces promotes well-being and recovery from stress.  相似文献   

青藏高原草地退化原因述评   总被引：23，自引：11，他引：23  

崔庆虎  蒋志刚  刘季科  苏建平 《草业科学》2007,24(5):20-26

导致青藏高原草地退化的因子很多,主要有气候、野生动物和人类活动等。在气候因素中以气温和降水的影响为主,短期内气候的变化不会成为草地退化的主导因素,从长期来看,气候变化与草地退化之间的相互作用可引起草地生态系统的退化;野生动物因素中主要以植食性小哺乳动物的影响为主,其危害程度取决于其种群数量的高低,同时大型野生草食动物对草地退化的影响也不容忽视;人类活动因素中主要以家畜过度放牧为主,在一定程度上,家畜放牧强度的高低直接决定草地的退化程度;草地退化是多种因素综合作用的结果。不同地区导致草地退化的主要因素不尽相同,导致青藏高原草地退化最主要的因子是过度放牧和植食性小哺乳动物种群爆发。针对退化的原因,提出了青藏高原退化草地恢复与管理过程中应注意的事项。  相似文献   

Total antioxidant activities,phenolics, anthocyanins,polyphenoloxidase activities of selected red grape cultivars and their correlations   总被引：1，自引：0，他引：1  

H. Hülya Orak 《Scientia Horticulturae》2007

Sixteen red grape cultivars (Md. Jean Matthias, Öküzgözü, Muscat Hamburg, Cabarnet Sauvignon, Tekirda? Çekirdeksizi, Gewürztraminer, 2B/56, Kalecik karas?, Carignan, Kokulu Siyah, Alfonse Lavallée, Bo?azkere, Adakaras?, Papazkaras?, Mourvedre and Cinsaut) which are grown in Tekirda? Viticulture Research Institute were analyzed for determination of antioxidant activities, total phenolics, anthocyanins, external colour, polyphenoloxidase activities, sugar and acidity. The lowest antioxidant activity (percentage of inhibition on peroxidation in linoleic acid system; AA) was determined in Tekirda? çekirdeksiz extracts as 87.58% and the highest AA was in Mourvedre (93.78%). Total phenolic content (TP) varied from 817 to 3062 μg/ml GAE in the same varieties, respectively. The total anthocyanin (TA) content ranged from 40.3 to 990.8 mg/l fresh weight. The lowest PPO activity was found in Bo?azkere and the highest was in Kalecik karas?. The total sugar content in the analyzed varieties varied between 13.29 and 24.46%. There was stronger correlation between AA and TP than AA and TA.  相似文献   

人类活动对晋西北地区生态环境影响的初步研究   总被引：9，自引：0，他引：9  

苏志珠 《干旱区资源与环境》1998,12(4):127-132

晋西北地处我国北方生态环境脆弱的农牧交错带,同时又是资源富集,资源与环境的矛盾十分突出。人类不合理的经济活动加剧了该区以土壤风蚀沙化和水土流失为主的环境退化问题。因此,加强环境保护刻不容缓。  相似文献   

读书活动与图书馆社会形象的树立     

周莲云 《农业图书情报学刊》2013,(12):89-91

开展读书活动是提高全民族科学文化水平的最佳途径.图书馆作为精神文明财富的社会公益性文化设施,要充分发挥自身职能,积极开展读书活动,努力创建行之有效的活动模式,掀起全社会的读书热潮,在精神文明建设中发挥其不可替代的作用.  相似文献   

猪屎豆种子脂溶性成分及其抗氧化活性研究   总被引：1，自引：0，他引：1  

张新蕊  王祝年  王茂媛  李文基  陈烁  罗丽娟 《热带作物学报》2011,32(9):1669-1672

运用气相色谱-质谱联用技术(GC-MS)对猪屎豆种子中脂溶性成分进行分析,应用色谱峰面积归一化法定量分析各成分的相对百分含量,共分离鉴定出37个化合物,占其总量的70.52%。同时采用清除DPPH自由基能力的方法对猪屎豆种子中的脂溶性成分进行抗氧化活性测定,结果显示一定的抗氧化活性,其IC50为560.3μg/mL。  相似文献   

湖北省成年人体质现状与体育活动的调查研究     

艾险峰  杜渐 《上海交通大学学报(农业科学版)》2013,(2):93-96

本研究以2010年武汉市全民体质监测数据为基础，对武汉市四个区的成年人体质健康现状和变化规律进行了调查和数据分析，以了解不同成年人组别、不同职业和性别群体成年人的体质差异。对照湖北居民参与体育锻炼情况的调查结果，本文探讨了成年人体质状况与体育活动之间的关联，以寻求改善成年人体质健康水平的有效途径和方法，为落实全民健身计划提供依据，提高全民健康尤其是成年人的健康水平。  相似文献   

Combined effects of salt stress and cucurbit downy mildew (Pseudoperospora cubensis Berk. and Curt. Rostov.) infection on growth,physiological traits and antioxidant activity in cucumber (Cucumis sativus L.) seedlings     

《Physiological and Molecular Plant Pathology》2013

Abiotic and biotic stresses both decrease quality and quantity of cultivated plants. We compared responses of Cucumis sativus L. cvs Sardes and Beith alpha which were treated with 50 or 100 mM NaCl and/or infected by Pseudoperospora cubensis Berk. and Curt. Rostov.. Both cultivars were affected remarkably when fungus infection was combined with salt stress however; cv Sardes was found out to be relatively tolerant with sustainable growth performance, better leaf water status and lower lipid peroxidation levels under this condition. This relative tolerance could be related to the fine tuning of the activities of the antioxidative enzymes and proline levels.  相似文献