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1.
采用四唑法和标准法分别测定苏丹草种子的生活力和发芽率,结果表明苏丹草种子生活力和发芽率之间具有极显著的正相关(r=0.775**)。经过试验和统计分析还显示,苏丹草种子的生活力和发芽率的结果相一致,即四唑法测定苏丹草种子生活力的结果可代表其发芽率的结果。  相似文献   

2.
本文对苏丹草种子寿命进行了研究。探讨了贮藏年限对苏丹草种子发芽率及活力的影响,对贮藏年限为1-10年的种子进行了发芽率,发芽指数,活力指数和电导率的测定结果表明:贮藏10年后的苏丹草种子发芽率仍达80%,说明苏丹草种子耐贮性高,种子寿命至少在10年以上,对贮藏1-10年种子的活力指数和种子寿命进行相关分析,呈负相关(r=0.9936**)高于种子发芽率与种子寿命的相关系数(r=-0.53),故用种子活力来估算种子寿命和种用价值是一种准确,快速,简便的方法。  相似文献   

3.
以3个不同品种的高丹草种子为材料,通过测定吸水率、电导率,四唑盐染色和荧光染色剂示踪等方法,研究了高丹草种子对物质渗漏的半透性差异,探讨了种子半透层的存在对电导率法测定种子活力的影响,为种子质量评价提供科学依据。结果表明,高丹草种皮对水分通透性良好,对四唑盐和电解质的通透性较差,完整高丹草种子的种胚四唑盐重度染色率较低[分别为5%(冀草2号)、0%(冀草8号)和2%(冀草008号)],不同发芽率种子电导率值无显著差异(P>0.05);刺破种皮后,种胚四唑盐重度染色率显著升高(3个品种均达100%),电导率与发芽率呈极显著负相关(P<0.01)。3种高丹草种子对荧光染色剂的通透性不同,其中冀草8号和冀草008号种皮限制荧光素的渗入。采用硝酸镧示踪结合X射线能量色散分析证明高丹草种胚包被物中存在半透层,该组织是引起种皮半透性差异的因素之一,其对电解质渗漏的阻碍,限制了电导率法对高丹草种子活力评价的应用。  相似文献   

4.
采用CO2激光器处理不同品种的苏丹草种子,研究植株生长发育状况及对激光处理后的反应,结果表明随着激光照射时间的延长,激光处理后的苏丹草发芽率与对照相比差异不显著,但在苗期和生长后期,处理后的苏丹草生长势比对照强,表现出植株生长旺盛,说明CO2激光处理苏丹草种子,有促进植物生长的作用。  相似文献   

5.
本文对3种类型苏丹草种子的活力进行了测定,结果表明在3种类型苏丹草种子中,以黑壳类型苏丹草种子活力最强,明显优于红壳和白壳苏丹草,而红壳和白壳苏丹草之间种子活力差异不明显;对3种类型苏丹草种子产量测定的结果也表现出与种子活力相同的结果,将种子活力与种子产量做相关分析后结果表明;3种类型苏丹草种子产量均与种子活力成正相关,即种子活力越强,种子产量越高。  相似文献   

6.
不同类型苏丹草种子醇溶蛋白的研究   总被引:1,自引:0,他引:1  
本文首次采用聚丙烯酰胺凝胶电泳法对不同类型苏丹草种子醇溶蛋白谱进行研究。结果表明,4种类型苏丹草种子酸溶蛋白谱带数量和活性都存在明显的种内品种和类型间差异。初步认为,苏丹草种子醇溶蛋白谱可以作为不同类型苏丹草的亲缘关系研究及其遗传差异鉴定的重要标志。  相似文献   

7.
本文对3种不同类型的苏丹草种子活力指数,过氧化物酶和酸性磷酸酯酶活性的测定结果表明,3种类型苏丹草种子活力差异显著,种子活力指数以黑壳苏丹草为最强,红壳苏丹草其次,白壳苏丹草为最低;过氧化物酶活性及酸性磷酸酯酶活性的测定结果也显示同样的规律。初步认为这3项指标可以作为苏丹草种子质量评价和品种选育的生理指标。  相似文献   

8.
聚乙二醇引发对几种牧草种子发芽率和活力的影响   总被引:26,自引:4,他引:22  
应用聚乙二醇(PEG)引发法探讨了不同引发渗透势、时间处理对无芒雀麦、苏丹草、沙打旺、小冠花、紫花芷蓿等牧草种子萌发和活力和有性在适宜处理下供试种子发芽速度、发芽率及活力指数分别显著高于对照;PEG的引发作用还表现为提高活力效应大于提高发芽率效应,学表明,低渗透势(-0.1、-1.2、-1.5MPa)引发处理对提高发芽率无作用;但处子早期萌发的效应对于沙打旺和小冠花种子的2仍很强烈,对苏丹草种子则  相似文献   

9.
研究了四唑液质量分数和染色前预处理对沙蓬(Agriophyllum squarrosum)种子生活力测定的影响,以及不同预处理方法破除沙蓬种子休眠的效果。结果表明,染色前刺破种皮法可缩短沙蓬种子四唑染色时间,以1.0%四唑溶液染色14~18 h效果最佳。种皮刺破法亦可有效地破除沙蓬种子的休眠,种子吸胀7 d后刺破种皮,各种样第2天种子即迅速萌发,第7天发芽率平均达92%,较未刺破种皮平均发芽率提高47%。  相似文献   

10.
试验以苏丹草种子为材料,采用二次通用旋转组合设计,研究了水分、NaCl复合胁迫对宁苜1号种子胁迫萌发指数(PI)的影响,结果表明:NaCl对苏丹草种子萌发有明显的抑制作用;水分对苏丹草PI影响不大,苏丹草种子萌发具有较强的耐旱性;水分、NaCl两因素对PI交互效应表现为:随着两因素的同时变化,PI表现出先增大后减小,两个因素共同作用下,PI最大,为64.12,两因素组合为盐分-1.414水平(浓度0)和0水平(6 ml),为苏丹草种子萌发较优组合。  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.
为贯彻落实《兽药生产质量管理规范》(简称《兽药GMP》),进一步推动兽药GMP实施进程,我部制定了《兽药生产质量管理规范检查验收办法》,现予公告。本公告自2003年6月1日起施行。附件:兽药生产质量管理规范检查验收办法二○○三年四月十日第一章 总则 第一条 为推动《兽药生产质量管理规范》(以下简称兽药GMP)的实施,规范兽药GMP检查验收工作,制定本办法。 第二条 农业部负责全国兽药GMP管理和检查验收工作;负责制修订兽药GMP检查验收管理规定;负责兽药GMP检查员队伍建设和监督管理工作,负责国际兽药贸易中GMP互认工作。 …  相似文献   

20.
以国际标准强毒R株人工感染非免疫产蛋鸡,定时扑杀,分别从鼻窦、眶下孔、气管、肺、气囊、卵巢和输卵管分离MG,并收集感染鸡所产蛋分离MG。结果表明,人工感染48小时后上、下呼吸道及肺已被全面感染,96小时气囊已被感染,120小时输卵管已能分离到MG,卵巢始终分离不到MG。人工感染鸡自144小时便能在其所产蛋中分离出MG。药物治疗能在72小时内消除感染,油乳剂苗则需24天后逐渐降低蛋内MG分离率,药物卵内注射、种蛋药浴、高温处理均能杀死卵内MG,但以研制的种蛋浸泡剂药浴效果为最好。  相似文献   

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