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1.
不同类型退耕地草被植物配置模式试验   总被引:2,自引:0,他引:2  
草被植物作为退耕还林还草、恢复植被的先锋植物,已成为共识。试验探讨了在以生态效益为主,兼顾经济收益的基础上,不同类型的退耕地草被植物配置模式。结论为:在土肥较好的土地上种植皇草、串叶松香草等,既能有效地覆盖地面,又能得到较高的经济收入;在土肥差的土地上种植紫花首蓿、白三叶,以及白三叶和苇状羊茅、黑麦草、鸭茅的混播组合,能培肥改良土壤。稳定地恢复植被。  相似文献   

2.
赖草属(Leymus Hochst)植物多数为优良牧草,是干旱地区特有的植物种群,内蒙古地区赖草属牧草种质资源很丰富,均被牧民认为是头等的饲用植物.经过多年工作,作者已发现和引种繁殖了结实性能比较好的赖草种群和生态类型,促进了赖草属牧草在生产中的推广应用.  相似文献   

3.
植物被各类病原物侵染后,发生一系列的生理生化变化,包括细胞壁变厚,产生植保素以及防御相关蛋白。本研究从病程相关蛋白编码基因的诱导和表达、在植物组织细胞中的分布和运输、生物学功能与抗病性的关系、转基因植物的研究等方面依次进行总结,并对草坪病害的研究进展以及病程相关蛋白在草坪草等植物抗病育种工作中的作用与前景进行了讨论。关键词:病程相关蛋白;植物抗病性;病害;抗病育种;草坪草  相似文献   

4.
铜锤草蜜源的观察与研究   总被引:3,自引:0,他引:3  
铜锤草在农田被作为杂草铲除,近些年来被园林绿化利用,但作为优良的蜜源还未见报道。通过2年多的调查研究和放蜂试验,阐述铜锤草作为河南省城市主要蜜源植物的数量、生物学特性及其栽培特点,影响其泌蜜的主要因素和对养蜂的价值。  相似文献   

5.
孙凡 《畜牧市场》2003,(8):12-13
皇竹草(Pennisetum hydridum)又称巨象草、王草、坚尼草为多年生,直立丛生的禾本科草本多年生植物,由象草和美洲狼尾草杂交选育而成,属四碳植物。通过在重庆璧山、北碚、万洲等地不同的生态环境下的种植示范,在无灌溉条件下长势良好。其产量、干物质、粗蛋白、粗脂肪等主要经济技术指标保持了较高的水平,是一种高产优  相似文献   

6.
三种野生岩生草本植物的抗旱性综合评价   总被引:7,自引:2,他引:5  
本试验选择自然状态下生长在岩石边坡上的3种野生岩生植物金发草和丛毛羊胡子草以及狗牙根为研究材料,通过盆栽干旱胁迫试验,研究和分析了干旱胁迫下3种野生岩生植物的叶面积指数、地下干物质量积累、叶片保水力;叶片相对电导率、可溶性蛋白、叶绿素等形态和生理指标,利用主成分分析法和隶属函数值法对影响3种野生岩生植物抗旱性的指标进行了分析评价。试验结果表明,3种草的抗旱性强弱顺序为金发草>狗牙根>丛毛羊胡子草。研究结果以期为筛选、培育适应于岩石边坡植被防护的乡土护坡植物的合理开发、利用提供理论依据。  相似文献   

7.
草本植物的非典型性应用   总被引:3,自引:1,他引:2  
草本植物通常用于观赏、牧草以及运动场草坪建植等。近年来,随着人民生活水平的提高,生活环境日益破坏,能源危机加剧,科学技术的发展以及研究的深入,越来越多的草本植物资源被开发出来,不论在深度上,还是在广度上都有了较大的发展,取得了显著成绩。但是我国植物资源非常丰富,还有许多颇具开发利用价值,至今仍被埋藏在深山中的野生草本植物有待研究、挖掘。主要从矿迹地恢复、造纸、提炼植物精油、用作能源草等方面对草本植物的非常规应用进行了阐述。草本植物在这些领域的发展和应用将提高草产品附加值,成为推动草产业化的一个重要部分。  相似文献   

8.
五色草的品种及应用   总被引:1,自引:0,他引:1  
用五色草进行造型,点缀街道、景点、装饰图案等,在城市绿化、美化工作中越来越显得重要,已成为城市绿化精品化的标志之一。但有关立体花坛的植物种类很多,其中五色草是主要的材料,目前,有关五色草的特征性介绍的材料并不多,在实践中造成许多混乱,影响五色草的应用和推广,不利于组织生产。因此,有必要对常见的五色草品种进行细致调查、比较,以利于应用,1.常见五色草的形态特征五色草又名五色见红绿草,常见的五色草指大叶红、小叶红、黑草、绿草和白草,但实际应用中不仅指这5种草,还有许多品种变异及五色草替代植物,常见的…  相似文献   

9.
火绒草及火绒草属植物研究进展   总被引:6,自引:0,他引:6  
火绒草,Leontopodium leontopodioides(Willd.)Beauv是菊科火绒草属植物的一种.别名薄雪草(陕西)、老头草、老头艾(东北)、小矛香艾(青海)、火绒蒿(河北)、大头毛香(甘肃)、白艾、棉花团花等.藏药名:扎托巴、巴娃呷波(阿坝藏语).蒙药名为孟根-阿给、海哥斯梭利.  相似文献   

10.
甘肃省赖草属植物种质资源与利用前景   总被引:6,自引:2,他引:4  
赖草属(Leymus)是禾本科(Gramineae)中一个具有横走根茎的类群。全世界约有30种;中国约有20种;甘肃省有6种,即毛穗赖草(Leymus paboanus)、窄颖赖草(L.angustus)、羊草(L.chinensis)、赖草(L.secalinus)、宽穗赖草(L.ovatus)和天山赖草(L.tianschanicus)。从赖草属植物分类研究的历史,甘肃省的赖草种类及分布以及赖草属植物的开发利用前景等进行了阐述。  相似文献   

11.
12.
在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。  相似文献   

13.
采用高效液相色谱法测定癸氧喹酯干混悬剂的含量,在2-250μg/mL范围内,峰面积的常用对数与进样量浓度的常用对数呈良好的线性关系,R^2=1(n=5),平均回收率为99.24%~99.51%,RSD在0.05%~0.28%。此方法分析时间短,样品前处理简便、定量结果准确,重现性好,结果满意,为其质量控制提供了依据。  相似文献   

14.
本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。  相似文献   

15.
REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air.  相似文献   

16.
用硝酸和高氯酸消化蜂蜜,使硒游离出来,在微酸性环境下,硒和2,3-二氨基萘(DAN)生成有较强荧光的物质,用环己烷萃取,在激发波长378nm,荧光波长518nm处测定其荧光强度。蜂蜜中硒含量范围:0.10~0.82μg/g。表明:蜂蜜应视为天然富硒营养品。  相似文献   

17.
乳酸杆菌益生作用机制的研究进展   总被引:2,自引:0,他引:2  
乳酸杆菌作为益生菌广泛用于人和动物。本文综述了乳酸杆菌改善宿主健康的机制。乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道。文章重点讨论了乳酸杆菌表面成分(表面蛋白、脂磷壁酸和肽聚糖)与肠道受体(C型凝集素受体、Toll样受体和 Nod样受体),阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制。  相似文献   

18.
Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo.  相似文献   

19.
乳酸杆菌作为益生菌广泛用于人和动物.本文综述了乳酸杆菌改善宿主健康的机制.乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道.文章重点讨论了乳酸杆菌表面成分(表面蛋白、脂磷壁酸和肽聚糖)与肠道受体(C型凝集素受体、Toll样受体和Nod样受体),阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制.  相似文献   

20.
OBJECTIVE: To determine whether serum concentrations of biomarkers of skeletal metabolism can, in conjunction with radiographic evaluation, indicate severity of osteochondrosis in developing horses. ANIMALS: 43 Dutch Warmblood foals with varying severity of osteochondrosis. PROCEDURE: 24 foals were monitored for 5 months and 19 foals were monitored for 11 months. Monthly radiographs of femoropatellar-femorotibial and tibio-tarsal joints were graded for osteochondral abnormalities. Serial blood samples were assayed for 8 cartilage and bone biomarkers. At the end of the monitoring period, foals were examined for macroscopic osteochondrosis lesions. RESULTS: Temporal relationships were evident between certain serum biomarkers and osteochondrosis severity in foals during their first year. Biomarkers of collagen degradation (collagenase-generated neoepitopes of type-II collagen fragments, type-I and -II collagen fragments [COL2-3/4C(short)], and cross-linked telopeptide fragments of type-I collagen) and bone mineralization (osteocalcin) were positive indicators of osteochondrosis severity at 5 months of age. In foals with lesions at 11 months of age, osteochondrosis severity correlated negatively with COL2-3/4C(short) and osteocalcin and positively with C-propeptide of type-II procollagen (CPII), a collagen synthesis marker. Radiographic grading of osteochondrosis lesions significantly correlated with macroscopic osteochondrosis severity score at both ages and was strongest when combined with osteocalcin at 5 months and CPII at 11 months. CONCLUSIONS AND CLINICAL RELEVANCE: The ability of serum biomarkers to indicate osteochondrosis severity appears to depend on stage of disease and is strengthened with radiography. In older foals with more permanent lesions, osteochondrosis severity is significantly related to biomarker concentrations of decreased bone formation and increased cartilage synthesis.  相似文献   

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