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植物生长调节剂对高羊茅草坪质量的影响 总被引：26，自引：0，他引：26
探讨了喷施不同浓度的矮壮素和一定浓度的多效唑对建植五年的高羊茅草坪质量的影响。结果表明,施用矮壮素可延缓高羊茅的生长速度,随着浓度的增加延缓作用加强,高羊茅的地下生物量及抗病性随矮壮素浓度增加而提高,低、中浓度的矮壮素改善了高羊茅的颜色、整齐度,随着浓度增加,这种作用由促进转为抑制,矮壮素以２００μｇ／ｇ浓度为宜;施用多效唑可延缓高羊茅的生长速度,促进地下生物量积累,增强抗病性,但抑制分蘖,对颜色 相似文献
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采用了不同浓度的多效唑(0．8、1．0、1．3mg／g)对高羊茅草坪进行叶面喷施，以研究多效唑对高羊茅生长特性的影响。结果表明：3种不同浓度的多效唑处理均表现出显著抑制高羊茅草坪草地上部分的伸长生长的效果，1．3mg／g的多效唑处理使高羊茅生长速度和修剪量明显降低，1．0mg／g的多效唑使高羊茅草坪草的密度显著增加，明显促进高羊茅的分蘖，却使高羊茅叶绿素含量明显降低。 相似文献
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多效唑在高羊茅草坪中的应用 总被引：2，自引：1，他引：1
在高羊茅Festuca arundinacea生长的旺盛季节,分别进行不同浓度的多效唑处理,研究多效唑对高羊茅生长的影响。试验结果表明:多效唑能使高羊茅叶绿素含量明显增加,节间显著缩短,茎增粗;高羊茅的株高随多效唑浓度的增加而降低;叶片大小也随多效唑浓度的增加而减小;多效唑处理高羊茅具有显著的抑制生长和改善绿化景观效果的作用。处理浓度以600~800 mg/kg为宜。 相似文献
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应用盆栽控盐的方法,研究施用不同浓度(200 mg/L、400 mg/L、600 mg/L)的多效唑对盐处理(0. 8%NaCl)高羊茅草坪草耐盐性的影响.结果表明,高羊茅在盐胁迫下表现出根长降低、生物量减少、相对含水量减少、丙二醛舍量增加等一系列变化.施用不同浓度多效唑后,能增加高羊茅生物量,提高根长,促进叶片可溶性糖的积累,保持更高的叶片相对舍水量,减少丙二醛的生成,从而在一定程度上缓解了高羊茅的盐害.400 mg/L多效唑对增加高羊茅耐盐性的效果最理想. 相似文献
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多效唑对盐胁迫下高羊茅耐盐性的影响 总被引：1，自引：0，他引：1
应用盆栽控盐的方法,研究施用不同浓度(200mg/L、400mg/L、600mg/L)的多效唑对盐处理(0.8%NaCl)高羊茅草坪草耐盐性的影响。结果表明,高羊茅在盐胁迫下表现出根长降低、生物量减少、相对含水量减少、丙二醛含量增加等一系列变化。施用不同浓度多效唑后,能增加高羊茅生物量,提高根长,促进叶片可溶性糖的积累,保持更高的叶片相对含水量,减少丙二醛的生成,从而在一定程度上缓解了高羊茅的盐害。400mg/L多效唑对增加高羊茅耐盐性的效果最理想。 相似文献
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多效唑对盐胁迫下高羊茅耐盐性的作用 总被引：3，自引：3，他引：3
应用盆栽控盐方法,研究施用不同质量浓度的多效唑(200、400和600 mg/L)对盐处理(0.8%NaCl)高羊茅Festuca arundinacea草坪草耐盐性的影响。结果表明,高羊茅在盐胁迫下表现出根长缩短、生物量减少、相对含水量减少、丙二醛含量增加等一系列变化。施用不同质量浓度多效唑后,能不同程度地增加高羊茅生物量,延长根长,促进叶片可溶性糖的积累,保持更高的叶片相对含水量,减少丙二醛的生成,从而在一定程度上缓解了高羊茅的盐害。在所有的处理中,质量浓度为400 mg/L的多效唑对提高高羊茅耐盐性的效果最佳。 相似文献
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在拔节期、孕穗期分别施用不同浓度的多效唑或矮壮素,对老芒麦种群的生殖投入参数(生殖枝密度及比例、花序生物量密度及比例、花序能量密度及比例等)、生殖收益参数(种子产量、成熟率、收益率等)和种子质量参数(千粒重、发芽指数、活力指数等)进行了比较分析。结果表明:生长抑制剂对种群生殖投入有极显著影响(P<0.01),抑制剂种类、浓度及施用时间对生殖枝密度、花序生物量与能量密度均有影响;多效唑显著促进种群花序生物量与能量累积,矮壮素则抑制种群生物量、能量向花序分配;拔节期施用比孕穗期施用更有利于种群的生殖投入。生长抑制剂对潜在种子产量、实际种子产量、成熟率及收益率均有极显著的影响(P<0.01),其中多效唑对种子产量的促进作用显著高于矮壮素,拔节期施用200～800mg/L的多效唑可显著提高种子产量(P<0.05),尤其是施用600mg/L的多效唑使潜在种子产量、实际种子产量分别比对照提高46.21%、65.89%,值得在生产中推广应用,但多效唑降低了种子成熟率与生殖投入收益率。生长抑制剂对种子千粒重、发芽指数与活力指数有极显著影响(P<0.01),拔节期施用可提高种子的发芽指数,孕穗期施用则降低发芽指数;抑制剂种类、浓度对发芽指数与活力指数的影响无明显规律。 相似文献
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魏静 《四川畜牧兽医学院学报》2009,(4):28-32
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
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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
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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
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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. 相似文献
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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