钙和赤霉素浸种对干旱胁迫下紫花苜蓿种子萌发的影响

为了探讨钙和赤霉素对紫花苜蓿(Medicago sativa)种子萌发的影响,试验采用纸上发芽法,测定了在聚乙二醇(PEG-6000)模拟干旱胁迫条件下,不同浓度的CaCl_2、赤霉素(GA3)以及GA3+Ca Cl2复合液浸种处理对紫花苜蓿种子萌发期发芽率、发芽指数、活力指数的影响。结果表明:用5 mmol/L CaCl_2、50 mg/L赤霉素(GA3)以及50 mg/L GA_3+5 mmol/L CaCl_2溶液浸种都能促进PEG胁迫下紫花苜蓿种子的萌发,提高紫花苜蓿种子的发芽率、发芽指数、活力指数,提高紫花苜蓿种子的活力。     

赤霉素对干旱胁迫下高羊茅萌发及幼苗生长的缓解效应

为研究PEG胁迫下赤霉素浸种对高羊茅种子萌发的影响,试验选用5个赤霉素浸种处理:0,100,200,300,400 mg/L,浸种后分别在0%,5%,10%,15%,20% 5个浓度PEG胁迫下进行萌发试验,对浸种后种子的丙二醛,电导率和萌发及幼苗生长情况进行测定。结果表明:0和100 mg/L赤霉素浸种后种子的电导率显著高于(P≤0.05)其他3个浓度,丙二醛含量显著低于(P≤0.05)其他3个浓度。随着PEG浓度的升高,对种子的萌发和幼苗的抑制作用逐渐增强,当PEG浓度高于15%时,种子发芽率和根,芽长有明显下降。在5%和10%PEG胁迫时,100 mg/L赤霉素与0 mg/L浸种相比发芽势提高了47.06%、37.33%,发芽率提高了19.46%、16.95%。在5%,10%PEG胁迫时,200 mg/L赤霉素与0 mg/L浸种相比根长分别提高了53.26%、30.12%,芽长提高了79.87%、50.75%,随着PEG胁迫增大,赤霉素缓解PEG胁迫抑制根芽生长的作用逐渐减弱。另外,PEG胁迫对芽长的抑制作用比根长更强,而且经赤霉素浸种后幼苗的根冠比明显变小。综上所述,促进高羊茅种子萌发,幼苗生长和缓解干旱胁迫最适宜的赤霉素浓度为100~200 mg/L。     

我国西北地区3个广泛种植苜蓿品种的萌发和生长对干旱胁迫的响应

采用聚乙二醇(PEG-6000)进行水分渗透胁迫,模拟研究了不同干旱胁迫环境对我国西北地区3个广泛种植的苜蓿品种:甘农一号杂花苜蓿(Medicago varia cv.Gannong No.1)、牧歌紫花苜蓿(Medicago sativa cv.Amerigraze401+Z)、新疆大叶紫花苜蓿(Medicago sativa cv.Xinjiang Daye)的萌芽和幼苗部分保护酶活性及幼苗叶片含水量的影响。结果表明,随着PEG-6000浓度的升高(PEG-6000浓度5%~25%),甘农一号杂花苜蓿、牧歌紫花苜蓿、新疆大叶紫花苜蓿的种子萌芽、幼苗叶片含水量及部分保护酶活性皆受到不同程度的影响。其中,3个苜蓿品种的发芽率、发芽指数、活力指数、发芽势皆明显降低,幼苗叶片含水量基本无显著变化,幼苗本体保护酶活性变化各不相同。利用隶属函数法分析得出3个苜蓿品种种子萌发期抗旱性强弱次序为:甘农一号杂花苜蓿>新疆大叶紫花苜蓿>牧歌紫花苜蓿,根据综合评价均值来看,甘农一号杂花苜蓿和新疆大叶紫花苜蓿抗旱性较强,而牧歌紫花苜蓿稍弱。     

重金属胁迫对青藏高原2种牧草种子发芽及生长的影响

为了探讨Zn~(2+)、Mn~(2+)、Fe~(3+)、Pb~(2+)胁迫对紫花苜蓿(Medicago sativa L.)、高羊茅(Festuca elata)种子发芽及生长特征的影响,试验采用组织培养法进行了Zn~(2+)、Mn~(2+)、Fe~(3+)、Pb~(2+) 4种重金属胁迫下,2种牧草的发芽试验,测定了2种牧草种子的发芽率、发芽势、芽长、根长、发芽指数和活力指数,分析了2种牧草种子对重金属的耐受性,以期为西藏中部矿区重金属污染土壤中牧草的混播提供科学依据。结果表明:在Zn~(2+)不同浓度胁迫下,2种牧草种子的相对发芽率、相对发芽势均表现出"低促高抑"的现象;Mn~(2+)胁迫时,紫花苜蓿的相对发芽率、相对发芽势均高于高羊茅,且差异显著(P0.05);当Fe~(3+)胁迫浓度为1 000 mg/L时,高羊茅的相对发芽率仍高于紫花苜蓿2倍,抗性比紫花苜蓿强;Pb~(2+)胁迫时,紫花苜蓿的相对发芽率、相对发芽势明显高于高羊茅,且达到显著水平(P0.05),Pb~(2+)浓度高于500 mg/L时,高羊茅已达致死剂量,高羊茅抗性比紫花苜蓿弱。从4种重金属对2种牧草相对根长和相对芽长的影响来看,2种牧草种子对4种重金属离子的抗性不同。从发芽指数和活力指数来看,紫花苜蓿对Zn~(2+)、Mn~(2+)和Pb~(2+)的抗性更强;高羊茅对Fe~(3+)抗性更强。说明紫花苜蓿和高羊茅2种牧草对重金属具有一定的耐性,其人工混播在矿区土壤修复中有一定的发展潜力。     

GA3处理对盐胁迫下5种牧草种子萌发及幼苗生长的影响

盐胁迫是限制种子萌发和幼苗生长的关键因子,适宜浓度的赤霉素(GA₃)可有效缓解盐胁迫对种子造成的不利影响。为了解GA₃对盐胁迫下牧草种子萌发和生长的缓解效应,筛选出促进盐胁迫下5种牧草种子萌发和幼苗生长的最佳GA₃浓度,本研究以100 mmol·L-1的NaCl溶液模拟盐胁迫,以黑麦草(Lolium perenne)、‘朝牧1号’稗谷(Echinochloa crusgalli ‘Chaomu1’)、羊草(Leymus chinensis)、紫花苜蓿(Medicago sativa)、白三叶(Trifolium repens) 5种牧草种子为试材,选取不同浓度GA₃进行浸种处理,测定其发芽率、发芽指数、根长、苗高、鲜重等指标。结果表明：GA₃浸种可有效缓解盐胁迫对5种牧草种子萌发和幼苗生长造成的抑制作用,且不同浓度间作用差异显著(P <0.05)。150 mg·L-1的GA₃能有效促进黑麦草、羊草、紫花苜蓿和白三叶种子的萌发和幼苗生长;100 mg·...     

紫花苜蓿化感作用的研究

通过培养皿砂培法的生物检测方法研究3种浓度(5%,7.5%,10% w/v)的紫花苜蓿Medicago sativa茎叶浸提液对受体植物黑麦草Lolium multiflorum cv.barspectra,高羊茅Festuca arundinacea cv.vegas,白三叶Trifolium repeus cv.haifa,红三叶T.pratense cv.common,萝卜Raphanus sativus cv.sijihong和紫花苜蓿浸提液自身幼苗生长及发芽的影响,以探明紫花苜蓿的化感作用.结果表明:7.5%和10%的紫花苜蓿茎叶浸提液对受体苗长、根长均产生明显的抑制作用,且随浓度的升高,抑制作用加强;适宜浓度处理的紫花苜蓿茎叶浸提液对黑麦草、高羊茅、红三叶、白三叶种子萌发具有明显的影响,发芽率明显降低.     

五氨基乙酰丙酸对逆境下草地早熟禾萌发及生长的影响

通过发芽试验,探讨不同浓度五氨基乙酰丙酸(5-ALA)对Cd胁迫、盐胁迫及干旱胁迫下草地早熟禾(Poa pratensis)种子萌发及幼苗生长的影响。本试验以草地早熟禾‘午夜’(Poa pratensis‘Midnight’)品种为材料,在Cd(2mg·L~(-1)),NaCl(50 mmol·L~(-1)),PEG(15%)3种处理下分别施加不同浓度的5-ALA(0,5,25,50,100mg·L~(-1)),分析了不同处理下种子发芽势、发芽率、可溶性蛋白等指标。结果表明:不同胁迫下较低浓度(5,25mg·L~(-1))5-ALA均能提高种子的发芽势、发芽率、芽长、根长等指标,而较高浓度(50,100mg·L~(-1))的5-ALA起抑制作用。综合比较4种不同浓度的5-ALA发现,25mg·L~(-1)对胁迫的缓解效应最优,其Cd胁迫下发芽势、发芽率分别比对照增加了21%,33.67%;NaCl胁迫下发芽势、发芽率分别增加了22.67%,23.67%;PEG模拟干旱胁迫下发芽势、发芽率分别增加了15.33%,10.67%。25mg·L~(-1) 5-ALA对NaCl,PEG胁迫下可溶性蛋白含量提高显著,分别提高了6.5和3.8μg·g-1,对于Cd胁迫,可溶性蛋白含量虽有提升但不显著。     

融雪剂对北方四种主要草坪植物种子萌发的影响

本试验用不同浓度的融雪剂对白三叶(Trifolium repens L.)、早熟禾(Poa annua L.)、紫羊茅(Festuca rubra L.)、紫花苜蓿(Medicago sativa L.)进行胁迫处理,研究融雪剂对4种草坪植物种子的发芽率、发芽势、发芽指数、胚根和胚芽长度的影响及其相关性。结果表明:在融雪剂胁迫下,除紫羊茅的发芽率在融雪剂浓度为3g(L-1时呈升高趋势外,其余草坪植物种子的发芽率、发芽势、发芽指数均随融雪剂浓度的升高而下降。4种草坪植物种子的融雪剂耐受性大小为紫羊茅白三叶紫花苜蓿早熟禾。     

酸铜对紫花苜蓿种子萌发及根系生长的影响

为探讨酸铜胁迫对紫花苜蓿种子萌发及根系生长的胁迫作用以及酸铜离子对紫花苜蓿危害的临界浓度,以非秋眠型紫花苜蓿品种"甘农5号"为研究对象进行酸性条件下铜离子胁迫浓度的种子萌发试验。研究结果表明:随着Cu2+浓度的增大,紫花苜蓿种子萌发指标和根系指标均不同程度的减小,其中发芽率、相对发芽率、发芽势和发芽指数呈极显著指数递减(P0.01);根据相对发芽率回归方式推导紫花苜蓿Cu2+半致死浓度为107mg/L,致死浓度为308mg/L。Cu2+胁迫浓度达到6.250mg/L时,幼苗的根系指标出现跳跃式下降,耐性指数显著下降,Cu2+6.250mg/L(pH 5)是紫花苜蓿胚根生长的敏感浓度。     

吉林省中西部地区优良牧草引种试验

通过对9个豆科牧草和11个禾本科牧草的引种试验,参照层次分析法综合分析了20个优良牧草的抗寒性、产量特性和品质特性.结果表明:公农一号苜蓿Medicago sativa cv.Gongnong NOⅠ,紫花苜蓿品种Medicago sativa cv.AC Lonview,公农无芒雀麦Bromus inermis cv.bromegrass,紫花苜蓿品种M.sativa cv.Rangelander和M.sativa cv.Algonquin居前5位,抗寒性强、产量高,品质优良,可在吉林省中西部地区推广应用.     

癸氧喹酯干混悬剂含量测定的改进

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。     

商会自治的基石——商会自治规范研究

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。     

猪毛色遗传的研究进展

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。     

中华人民共和国农业部公告 第267号

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。 …     

鸡败血支原体垂直传播模式及其阻断方法

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。     

Comparison of 2 methods of centesis of the bursa of the biceps brachii tendon of horses

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.     

不同样本商品蜂蜜中硒含量的测定

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。     

乳酸杆菌益生作用机制的研究进展

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。     

Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF

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.