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利用塑料薄膜覆盖、遮阳网覆盖和草帘覆盖,观测野生狗牙根(Cynodon dactylon)返青初期叶片、茎和根茎各组织器官的形态特征,测定叶绿素含量、相对含水量、可溶性糖、可溶性蛋白含量和保护酶活性等生理生化指标,以揭示不同覆盖处理下狗牙根各组织器官的生理响应.结果表明:经覆盖处理的狗牙根返青率在88.67%以上,而未覆盖的狗牙根植株全部死亡;草帘覆盖处理的狗牙根草坪盖度、株高、叶绿素含量显著高于遮阳网覆盖,而丙二醛含量及质膜透性显著低于遮阳网覆盖,效果最好;塑料薄膜次之,遮阳网较差.狗牙根各器官对覆盖物的响应表现出根茎 >叶片 >茎. 相似文献
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(一)塑料暖棚的选址 选择背风向阳,地势平坦干燥的地方建棚. (二)建棚材料的选择和使用选择保温性能好的塑料,用聚氯乙烯薄膜和聚乙烯薄膜均可,而聚氯乙烯薄膜的保温性能更好.采用多层覆盖,一方面覆盖双层棚膜,夹层间形成空气隔绝层,防止对流的发生,可比单层提高温度2～3℃;另一方面在棚膜上覆盖草帘等覆盖物.白天卷起固定在棚顶,夜间放下.各草帘间的结合部要有适当宽度的重叠.另外,密封好塑料薄膜边缘缝隙,及时修补破损部位,门口要挂门帘. 相似文献
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以中粗沙、极细沙和粉粘粒、泥炭为配材,采用极端顶点配方试验设计,参照美国高尔夫协会(USGA)规范建立高尔夫果岭试验小区,对6种不同配方土壤的微生物数量(细菌、真菌、放线菌)、酶活性、狗牙根(Cynodon dactylon)草坪性状及其相关关系进行研究,以了解不同基质对新建果岭土壤微生物、酶活性及草坪性状的影响.结果表明:新建狗牙根果岭成坪后微生物数量、酶活性均较植草前显著增加;含泥炭的基质中微生物数量和酶活性水平、地上地下生物量、草坪质量显著高于全沙基质(P＜0.05).中粗沙、泥炭的含量及pH值与微生物数量、酶活性和草坪性状关系密切.各种土壤微生物数量和酶活性的增加能促进新建高尔夫果岭草坪的地上、地下0～5 cm、10～20 cm及地下生物总量和草坪表观质量的增加,而对地下5～10 cm生物量的影响较小.土壤微生物和酶的共同作用能促进高尔夫果岭草坪健康生长. 相似文献
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菇渣堆肥对土壤及草坪生长的影响 总被引：5，自引：0，他引：5
为了解决城市草坪绿地土壤性状恶化问题和有效利用菇渣资源,进行了菇渣堆肥绿地土壤改良试验,通过混合(H)、覆盖(F)、混合+覆盖(HF)处理,研究菇渣堆肥不同施入方式对绿地土壤物理性质及草坪生长的影响.结果表明:三种施入方式均能显著降低表层(0～10cm)土壤容重,增加土壤孔隙度,F和HF改良效果最理想;各施人方式均能显著提高土壤渗透性,具有显著的保水作用,含水量由高到低依次是F＞ HF＞H,分别比对照高31％、23％、16％.不同施入方式还均能显著促进草坪生长和分蘖,增加草坪地下生物量,其中F处理的分蘖密度和地下生物量最高,分别比对照高46％和35％ ;F处理的杂草抑制宰在98％以上,HF为56％,H处理未能抑制杂草;依据NTEP对草坪外观质量综合评分,覆盖处理6.73分,草坪质量良好,混合覆盖与混合处理分别为5.91分和5.55分,草坪外观质量尚可;F与HF处理还能减缓土壤温度变化幅度. 相似文献
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(一)注意保温早春季节,昼夜温差大,白天可放大巢门,晚上则应缩小巢门,并在箱内巢脾两侧加棉花,上面盖上棉垫.蜂箱外侧和底部覆盖干草,箱上盖草帘,再蒙上塑料薄膜.春末撤去覆盖物时,应先撤强群,后撤弱群;先撤上面,后撤四周和箱底.箱内保温物应随巢门扩大而逐渐撤去. 相似文献
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果岭是高尔夫球场中要求最精细的草坪区域,关系到场地的可打性,影响球场的运营。简便实用的果岭草坪质量评价方法有助于制定科学合理的球场养护管理策略,提高果岭草坪质量。本研究依据现有的草坪质量评价理论与评价标准,选取果岭速度、果岭硬度、病害面积比例、修剪高度、平滑度和外观质量6个指标因子,将评判法和打分法相结合,尝试构建较为科学简易的果岭坪用质量评价方法,以期为高尔夫球场提供针对性的养护改进意见。6月果岭的综合得分67分,对得分较低的指标进行重点养护管理,10月果岭综合得分提升到86分。研究表明,依据该方法提出的养护方式切实有效,有一定的实用性。 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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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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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