几种冷季型草坪植物基本特性的比较及其管理措施

冷季型草坪植物主要栽植于寒冷湿润和寒冷半湿润地带。其最适生长气温为15-25℃，具有一定的抗寒能力。在美国，绝大多数冷季型草坪草都能在寒冷湿润带栽植，它们有剪股颖、早熟禾、狐茅和多年生黑麦草等属的一些植物，特别是草地早熟禾、匍匐剪股颖和细弱剪股颖、紫羊茅、羊茅和粗茎早熟禾主要栽植在北寒冷湿润带，这些草不耐热和干旱，     

11种优良坪用禾草对禾草云斑病抗性的初步研究

１９９７～１９９８年选用１１种坪用禾草品种在自然条件下做了对禾草云斑病的抗性鉴定。结果表明,结缕草、细叶结缕草及狗牙根不发病,表现免疫;高羊茅抗病;草地早熟禾、紫羊茅、黑麦草及匍茎剪股颖发病较重,表现感病。     

禾顶囊壳小麦变种对草坪禾草的致病性研究

应用人工接种法测定了禾顶囊壳小麦变种中国菌系对草地早熟禾、多年生黑麦草、匍茎剪股颖、高羊茅、硬羊茅和狗牙根等6种草坪禾草24个品种的致病性。结果表明,该菌对供试各草种都能正常致病,引起典型全蚀病症状。大多数供试品种的病根率和病根严重度都很高,属于感病类型,仅匍茎剪股颖的绿宝石品种具有中度抗侵入性和高度抗侵染性,高羊茅Shorter品种和硬羊茅参试品种具有中度抗侵染性。由于该菌引起的小麦全蚀病在我国分布广泛,可以提供大量菌源侵染草坪禾草,从而对草坪构成严重威胁。     

植生带草坪的建植入管理技术

１９９７～１９９８年对植生速草坪的建植及管理技术研究表明：选择草地早熟禾、剪股颖及多年生黑麦草按５：４：１的比例混播植生带,采取床土覆沙、及时浇水、定期修剪、适当追肥、及时防除杂草和病虫害,建坪当年的草坪其密度、盖度、色泽等各项指标均可达到５级标准。     

剪股颖属植物遗传分化及系统关系的分子标记研究

剪股颖属植物形态变异大、倍性复杂、种间易于杂交,导致异名多、分类混乱。本研究采用4种分子标记技术,对包括匍茎剪股颖、巨序剪股颖及红顶草在内的7种剪股颖,共58个个体的遗传分化和系统关系进行研究。根据谱带清晰程度及多态性,筛选出9个RAPD引物、2个SSR引物、5个ISSR引物及1个SCAR标记,并建立了最适的PCR反应条件。采用最大简约法和距离法对7种剪股颖植物进行系统树分析,并用靴带检验法计算内部分支的支持率。启发式搜索得到的简约树和由UPGMA方法得到的表征树近乎相同,其中,匍茎剪股颖和红顶草构成单系类群并得到100%的置信支持。红顶草显示了匍茎剪股颖特异性特征谱带,但同时具有不同于匍茎剪股颖的遗传分化,支持将红顶草视为匍茎剪股颖一个变种的观点。对匍茎剪股颖与巨序剪股颖间的遗传分化进行了探讨。     

甘肃河西荒漠气候区草坪草种引种试验报告

试验认为，最适宜河西荒漠气候区建植草坪的草种是草地早熟禾、瓦巴斯早熟禾、羊茅、紫羊茅；其次是匍匐剪股颖、细弱剪股颖及小糠草。另外，在有完善剪草机械的条件下，多年生黑麦草、无芒雀麦及鸡脚草亦可建坪。     

施用矮壮素对匍茎剪股颖草坪的影响

采用矮壮素生长延缓剂对匍茎剪股颖进行处理后，能有效减缓匍茎剪股颖地上部生长，提高根冠比，增强抗逆性，降低和衰竭，减少草坪杂草，促进分蘖，可使叶片变短增厚，降低草坪管理成本，提高草坪观赏价值，效果显著。     

荒漠区城镇绿化草坪的适应性及持续发展研究

根据多年在武威、张掖、酒泉等河西城镇、公园及旅游区中不同草坪草种的种植实践,进行了不同覆盖材料、不同立地和不同灌溉条件下的草坪种植试验;对各草种进行了多年的跟踪调查,观测其越夏率、越冬率、持续生长年限及年内各月的适应性表现及物候观测等。结果表明:河西地区气候干旱,建植草坪时,选用草帘、麦草、沙粒等低成本覆盖材料,均可一次性成功建坪。多年生黑麦草Lolium perenne的品种适应性较差,3~5年内在草坪中消失,其他一些种及品种3~5年内的越冬、越夏率可达90%以上。绿洲土上建植草坪最优,其生长良好,持续年限长,适应性最强;其次为绿洲盐碱土、灰棕荒漠土和风沙土,种植时需根据具体情况改土。草坪草生长的耐高温程度表现为高羊茅Festuca arundinacea、匍匐剪股颖Agrosstis stolo-nifera>紫羊茅Festuca rubra、多年生黑麦草>草地早熟禾Poa pratensis;耐低温程度表现为匍匐剪股颖>草地早熟禾>高羊茅、紫羊茅>多年生黑麦草;耐旱性表现为高羊茅、紫羊茅>草地早熟禾、多年生黑麦草>匍匐剪股颖。风沙土上建植草坪灌溉量最大;其次为灰棕荒漠土、盐碱土;绿洲土灌溉量最小。     

四种冷季型草坪植物对镉的耐受性与积累特性

高羊茅、草地早熟禾、多年生黑麦草和匍匐剪股颖在镉(Cd)污染土壤上有很高的耐受力,但它们对Cd的耐受性和积累能力鲜有报道。4种冷季型草坪植物在不同Cd浓度(50, 100, 200, 400 mg Cd/kg)下处理60 d,本文对4种草坪植物在Cd胁迫下的生理响应及地上部和根系的Cd含量进行了研究。从Cd胁迫对草坪植物的草坪质量、相对生长速率、草坪密度、地上部和根系的生物量、叶片电导率、叶片相对含水量和叶片光化学效率的影响可以看出,高羊茅对Cd的耐受性最好,其次为多年生黑麦草,再次是草地早熟禾,匍匐剪股颖对Cd的耐受性最差。本研究还发现草坪植物在Cd胁迫下,叶片相对生长速率和根系生物量比其他的生理指标敏感。4种草坪植物地上部和根系的Cd浓度和积累量随着处理浓度的增加而增加。在相同Cd浓度处理下,草地早熟禾地上部Cd浓度最高,高羊茅和匍匐剪股颖次之,多年生黑麦草地上部的Cd浓度最低。4种草坪植物中根系Cd浓度最高的是多年生黑麦草。在50~400 mg Cd/kg处理下,草地早熟禾的转运系数和萃取率最大,多年生黑麦草的转运系数和萃取率最小。在相同Cd处理水平下,草地早熟禾地上部的Cd积累量比其他3种草坪植物高,匍匐翦股颖根系生物量低导致其根系的Cd积累量最低。本研究结果表明,4种草坪植物对Cd有较强的耐受性和积累能力,它们具有应用于Cd污染土壤上植物固定的潜力。     

长江中下游地区常绿草坪草的栽培

长江中下游地区常绿草坪草首选品种为匍茎剪股颖和细弱剪股颖 ,其次为高羊茅、草地早熟禾。同时 ,明确了要保持草坪草的常绿必须配备高质量的栽培管理措施 ,如夏季降土温 ,生长旺季的合理修剪和肥水的管理等     

The effect of Plasmodium gallinaceum on a challenge infection with Ascaridia galli in chickens

The effect of a primary infection with the haemoparasite Plasmodium gallinaceum on the establishment of a challenge infection with the nematode Ascaridia galli in chickens was studied. Four groups were infected as follows. Group 1: inoculated intravenously with 10(6) P. gallinaceum-infected erythrocytes on day 0; group 2: orally infected with 500 embryonated A. galli eggs on day 10; group 3: infected with P. gallinaceum on day 0 and A. galli on day 10; and group 3: non-infected control birds. The results of this investigation demonstrates that a primary infection with P. gallinaceum in chickens alters the course of a subsequent infection with A. galli. Thus, an antagonistic effect was seen in which the malaria infection caused a significant reduction on the establishment of the nematode in concurrently infected animals.     

Increased establishment of lungworms (Dictyocaulus viviparus) in calves after previous infections with gastrointestinal nematodes (Ostertagia ostertagi and Cooperia oncophora)

The influence of a priming infection with gastrointestinal nematodes on the subsequent establishment of lungworms was studied. Repeated inoculations of calves with Ostertagia ostertagi and Cooperia oncophora during 3, 5 or 7 weeks resulted in an establishment of lungworms that was 191% of the establishment found in na?ve controls. The higher take was associated with a higher faecal output of lungworm larvae and with lower weight gains of calves. The effect was not significantly influenced by the duration of the primary infections or by the actual presence or absence of worms in the gastrointestinal tract.     

伪狂犬病基因缺失疫苗SA215抗强毒潜伏感染能力

通过建立能鉴别野毒和疫苗毒的多重PCR,确定试制的伪狂犬病基因缺失疫苗SA215对强毒潜伏感染的建立及随后被激活的影响。同时模拟了田间条件下对野毒潜伏感染猪接种的安全性和接种对已建立的潜伏感染的影响。结果表明,接种伪狂犬病基因缺失疫苗SA215在一定程度上能阻止强毒潜伏感染的建立和随后的激活。试制的疫苗对潜伏感染猪接种安全,对潜伏感染的消除有一定的作用,但不明显。     

The establishment rate of a sheep nematode: revisiting classics using a meta-analysis of 87 experiments

Strongyle nematode establishment rate in their host is a highly variable life history trait, which makes it difficult to estimate. A meta-analysis was applied to the nematode Teladorsagia circumcincta of sheep in order to acquire a general framework of the factors modulating this life trait. A linear model was built with individual data on 540 infected lambs extracted from 13 articles. Lambs breed and age, time lag between last infection and the interaction between infection mode, infective dose and the number of repeated infective doses were significantly related with the establishment rate. The influence of infection mode on nematode establishment rate was also evaluated by comparing nematode establishment rate distributions within lamb populations infected under different conditions. Natural and repeated experimental infections lead to similar distribution of establishment rate. Conversely, these infection conditions resulted in different parasite establishment rates in average (12.7 and 23.4%, respectively). Three hypotheses are discussed to explain this result: immune protective response, host avoidance behaviour and parasite virulence.     

福建高速公路生物护坡草坪的建植与养护

分析了福建高速公路所经区域的土壤、气候及草坪植被环境特点，归纳总结了高速公路生物护坡草坪的建植与养护技术，对草种选择，建植与养护，质量保障等进行讨论并提出了建议，旨在提高高速公路生物护坡草坪的建植与管理技术水平。     

仔猪出生顺序、出生重、性别对乳头序列确定及增重的影响

主要研究仔猪出生顺序、出生重、性别等因素对乳头序列确定以及一周龄仔猪增重的影响。试验发现仔猪乳头序列的固定时间在不同窝之间存在很大差异,乳头固定受诸多因素的影响。固定过程中仔猪可能会改变偏好乳头,仔猪越频繁的更换乳头就越难固定乳头。出生重较大的仔猪初次确定偏好乳头的时间和乳头序列最终固定的时间都较短,并且增重明显较多。出生顺序、性别对乳头序列影响不显著,对仔猪增重的影响也不明显。     

Resistance to prophylactic treatment with macrocyclic lactone anthelmintics in Teladorsagia circumcincta

Sixty-four Romney ewe lambs were allocated to 12 groups on the basis of liveweight. Four groups (n=5) were administered oral ivermectin (IVM), 4 (n=6) oral moxidectin (MOX) and the remaining 4 (n=5) controlled-release capsules containing IVM (IVM-CRCs). Nine and 10 days later, the groups within each treatment type were challenged with infective-stage larvae (L3) of 1 of 4 different isolates of Teladorsagia circumcincta (two doses each of 5000 L3). The first of these (S) was known to be anthelmintic-susceptible; the second (OR) was a multiple anthelmintic-resistant strain recovered from the field following therapeutic failure of both ivermectin and moxidectin and subsequently maintained in the laboratory without further anthelmintic selection; the third (R) was derived from OR but had been passaged for five generations indoors with each generation being screened with all three broad-spectrum anthelmintic classes; and the fourth (RxS) was an F1 cross between the R and S isolates. As anticipated, because of its limited residual activity, IVM had no significant effect on the establishment, 9 and 10 days post-treatment, of any of the parasite isolates. In contrast MOX, which has greater residual activity, was highly effective at preventing the establishment of the S isolate but showed no significant effect against the OR, R or RxS isolates. The IVM-CRC was also highly effective at preventing the establishment of the S isolate and furthermore it significantly reduced establishment of both the OR and RxS isolates, although it had no significant effect against the R isolate. The results suggest that with respect to the establishment of T. circumcincta L3s following anthelmintic treatment, macrocyclic lactone (ML) resistance is effectively a dominant trait in the presence of MOX, while it behaves as a partially dominant/recessive trait under treatment with IVM-CRCs. The potential implications of this finding in relation to selection for ML resistance in T. circumcincta are discussed.     

Enriched Topographic Microsites for Improved Native Grass and Forb Establishment in Reclamation

Low seed germination and seedling establishment are the greatest challenges for revegetation success. Topographic microsites are known to enhance seed germination and seedling establishment due to their unique soil properties and provision of shelter from elements and herbivores; soil amendments can supply organic matter and nutrients for plant establishment and growth when limited. We investigated the effect of three topographic microsites and six soil amendments and their additive effects on three disturbed grasslands in central and southern Alberta, Canada. Treatments were topographic microsites of mounds, pits, and flats, with and without amendments (erosion control blanket, hay, straw, manure, hydrogel, control) and were seeded with four native grasses and three native forb species. Seedling emergence and survival and soil temperature and water content were assessed over two seasons and plant cover over three seasons. The effect of microsites and amendments was not additive. The addition of erosion control blanket, hay, and straw to flat sites was just as productive as on topographic microsites. These amendments increased grass and forb emergence and buffered soil temperature. Mounds increased first year forb emergence and reduced over winter survival rates for grasses and forbs. Pits were not beneficial for revegetation. The effect of topographic microsites and amendments was influenced by site conditions.     

Effect of the consumption of Lysiloma latisiliquum on the larval establishment of gastrointestinal nematodes in goats

The consumption of tannin-rich (TR) forages has been associated with negative effects against gastrointestinal nematodes and with an improved host resilience. It has been hypothesized that tannins affect the capacity of infective larvae to establish in the mucosae of the host. In this study, we aimed at testing this hypothesis using Lysiloma latisiliquum, a tropical TR tree. The objectives were: (i) to evaluate the effect of the consumption of L. latisiliquum on the establishment of nematode third-stage larvae (L3) in goats; (ii) to define the role of tannins in these effects in vivo by using an inhibitor (polyethylene glycol, PEG); and (iii) to examine a possible indirect effect of tannins on the inflammatory response in the digestive mucosa. Eighteen Criollo goats composed three experimental groups. The control group received fresh leaves of Brosimum alicastrum, a plant with a low level of tannins. Two groups received L. latisiliquum leaves either with (L.L.+PEG) or without (L.L.) daily addition of 25g PEG. After a 7-day adaptation period, each goat was infected with both Haemonchus contortus and Trichostrongylus colubriformis (3000 L3 per species). The goats were slaughtered 5 days after infection and worm counts and histological analyses were performed. No difference in the voluntary feed intake of foliage was observed between the 3 groups. The consumption of L. latisiliquum significantly reduced the larval establishment of both nematode species compared to the control (P<0.01). For both worm species, the effects were totally alleviated with PEG (L.L.+PEG group), suggesting a major role of tannins in the observed effects. Only minor differences in the mucosal cellular response were observed between the 3 groups. These results confirm that the consumption of TR plants reduces the establishment of nematode larvae in the host and that a direct effect is principally involved.     

不同氮肥和基质类型对匍匐翦股颖草坪质量的影响

为了更好地了解不同氮肥和基质类型对高尔夫果岭草坪质量的影响,在温室里模拟果岭用PVC管建造4种基质类型的匍匐翦股颖Agrostis stolonifera cv.Prenncross草坪,出苗后施用Hoagland和Arnon营养液培育至成坪,成坪后选用速效氮尿素和控释肥丁异叉双缩脲进行氮肥类型处理。试验结果表明,基质类型对匍匐翦股颖的生长和坪用质量有着显著影响并表现出阶段性差异。4种基质类型的草坪成坪速度快慢顺序为：土壤基质>改良沙基质>半改良沙基质>纯沙基质,这也是表层有机质累积量的大小顺序;外观质量高低为：改良沙基质>半改良沙基质>纯沙基质>土壤基质;在播种建坪的初期施用速效氮肥有助于匍匐翦股颖的生长和快速成坪;缓释氮肥释放速率慢,更符合草坪成熟后对氮的需求规律。缓释氮肥起效慢,应在草坪逐渐成熟时与速效氮肥搭配施用。