长江1号苇状羊茅在边坡植被群落中的变化规律

通过对长江1号苇状羊茅与4种草种混播后的草坪观测,发现其与普通狗牙根组合对边坡植被覆盖度较好,达到95%。4种混播草坪的根系地下分布也以长江1号苇状羊茅+普通狗牙根组合根系之间的交错程度最致密,同时通过对4种混播草坪护坡效果及长江1号苇状羊茅的优势度测定,得出长江1号苇状羊茅适宜在四川地区用于边坡护理,长江1号苇状羊茅与狗牙根混播护坡固土效果较好。     

南过渡带混播草坪组合研究

在南过渡带的生境及一定的养护条件下,对多种混播草坪组合设计进行了评比,结果表明:混播组合高羊茅(Festuca arundinacea)凌志40%+高羊茅锐步30%+早熟禾(Poa pratensis)男爵20%+黑麦草(Lolium perenne)顶峰10%表现最好,其次为高羊茅凌志30%+高羊茅锐步30%+早熟禾巴润20%+黑麦草顶峰20%;其余表现不好。从苗期表现来看,黑麦草及高羊茅的比例高者表现好。从成坪后期来看,黑麦草的比例不宜过多,最好不超过20%。混播组合中,随着草坪利用年限的延长,高羊茅的比例稳定,开始时黑麦草及早熟禾的比例有所下降,但早熟禾的比例在后期又有所增加。翦股颖(Agrostis stolonifera)宜作单播草种,狗牙根(Cynodon dactylon)可与高羊茅或早熟禾混播使用。综合考虑成坪速度、草坪质量及病虫害等各方面的因素,混播比例最佳配合为高羊茅∶早熟禾∶黑麦草=7∶2∶1;混播组合为高羊茅∶早熟禾∶黑麦草=6∶2∶2表现也很好,建议使用。高羊茅由多个品种组成的表现更佳。     

贵州南部混播草地几种建植因素最佳组合研究

选用苇状羊茅、多年生黑麦草、扁穗雀麦、蔬花雀麦、白三叶和紫花苜蓿等六种牧草,采用Ｌ９（３＾４）正交试验设计,探讨了在贵州南部地区生态条件下建立永久型优质人工混播草地最佳的草种组合、豆禾比例、播种量和播种方式。结果表明,草种组合是主要因素,播种量次之,用种比例和播种方式无明显影响;贵州南部地区优质永久型人工混播草地的理想草种组合是苇状羊茅＋多年生黑麦草＋扁穗雀麦＋白三叶（或紫花苜蓿）,豆科和禾本科的     

黑麦草、高羊茅、早熟禾成坪期生长势与分蘖力测定分析

探明特定生态环境草坪草种地上营养器官茎、枝(蘖)、叶的生长发育特点,不同品种组合表现特性是一个地区开展草坪建植的重要依据,此测定分析显示四川西南部亚热带暖温区秋播冷季型草生长势强的优势种是高羊茅、黑麦草,生长发育较慢的优势种为早熟禾;组合比例初步看出高羊茅、黑麦草约占80%,早熟禾约占20%为好;组合播种量初步指出以15～30g/m2为宜。     

黑麦草、高羊茅、早熟禾成坪期生长势与分蘖力测定分析

探明特定生态环境草坪草种地上营养器官茎、枝(蘖)、叶的生长发育特点,不同品种组合表现特性是一个地区开展草坪建植的重要依据,此测定分析显示四川西南部亚热带暖温区秋播冷季型草生长势强的优势种是高羊茅、黑麦草,生长发育较慢的优势种为早熟禾;组合比例初步看出高羊茅、黑麦草约占80%,早熟禾约占20%为好;组合播种量初步指出以15～30g/m2为宜.     

退耕坡地不同草种组合建植草地的研究

利用灰色系统理论中的关联度分析方法，以草地盖度，粗蛋白含量。生物量，草地越冬夏率对不同草种组合建植的退耕坡地的草地进行综合评价。结果表明贵州省中部地区退耕坡地适宜的草种组合为：白三叶，早熟禾，多年生黑麦草，苇状羊茅，扁穗雀麦。     

关中地区矮砧密植苹果园草种组合方案筛选

矮砧密植苹果种植技术的推广普及,为果园生草技术提供了广阔市场空间,同时也对规范化和标准化果园生草技术的应用提出了更高要求,一般单播草种难以满足矮砧密植苹果园现代化管理的要求。为此,在关中地区矮砧密植苹果园对5个不同草种组合方案的生长特性进行比较评价,旨在筛选出适宜的草种组合方案。结果表明,70%苇状羊茅(Festuca arundinacea)+20%草地早熟禾(Poa pratensis)+10%多年生黑麦草(Lolium perenne)组合方案不仅出苗较快、绿期较长,而且草地平整度极好,非常符合矮砧密植苹果园生产机械作业的要求;30%苇状羊茅+30%多年生黑麦草+20%鸭茅(Dactylis glomerata)+20%草地早熟禾组合方案出苗快、再生性好、绿期中等、持久性好,符合果园人工管理的要求,是关中地区矮砧密植苹果园生草较理想的组合方案;50%白三叶(Trifolium repens)+20%鸭茅+30%多年生黑麦草组合方案,草地种群中白三叶占比逐年增加,到建植第3年占比超过50%,持久性好,亦可刈割后制作青贮或青饲家畜,也是关中地区矮砧密植苹果园生草较理想的组合方案之一。     

细羊茅在北京地区的引种适应性研究

在引种栽培 16个细羊茅草种的基础上 ,对这些草种在北京地区的适应性进行了系统的总结 ,分析了这些品种建坪的质量 ,包括生长特征、特性 ,草坪越冬、越夏性 ,抗病虫性 ,抗热性等指标 ,对细羊茅草坪的管理提出了建议。结果表明 :细羊茅类草种较难适应北京地区夏季炎热的气候条件 ,应予以限制性利用。     

天津市草坪混播技术的研究

通过对天津市的主栽草种高羊茅、黑麦草、草地早熟禾的111个品种植物学特征和生物学特性的观察及不同比例的混播试验研究,得出天津立地条件下,不同类型的混播组合8个。     

优良禾草苇状羊茅改良退化人工草地试验研究

在贵州南部气候条件下，采用苇状羊茅、多年生黑麦草、扁穗雀麦、白三叶等4种优质牧草，通过不同的处理组合对多年生黑麦草割草地进行带状改良，结果表明：凡含有苇状羊茅的处理组合改良效果较好，草地植被特征增强，耐牧性能提高；改良方式中窄带改良比宽带改良效果好。生产实际中建议采用窄带改良方式，选用苇状羊茅十多年生黑麦草＋白三叶这个草种组合，以达到增强草地植被特征、优质、持久、耐牧等目的。     

Induction of tall fescue toxicosis in heat-stressed cattle and its alleviation with thiamin

Livestock grazing endophyte (Acremonium coenophialum)-infected tall fescue (Festuca arundinacea Schreb. cv. Kentucky 31) at high ambient temperatures may suffer from fescue toxicosis. Adult Angus cows (Bos taurus) were fed 0 to 1 kg/d of 70% infected tall fescue seed containing about 4.4 g of loline alkaloids in factorial combination with thiamin at 0 or 1 g/d. Cows assigned to the zero level of tall fescue seed received a supplement of equivalent energy and protein. Ingestive behavior was measured at 1330 to 1430 EDT during two 4-d periods in two consecutive weeks in August on alfalfa (Medicago sativa L.) pastures using a tethered grazing system. Alfalfa intake per measured grazing session of cows given tall fescue seed declined linearly (P less than .01) as air temperatures during grazing increased above 25 degrees C, largely because of shorter grazing meals. Thiamin increased alfalfa intake per measured grazing session by extending grazing time. Alkaloids in ingested endophyte-infected tall fescue induce thiamin deficiencies in cattle that result in symptoms of tall fescue toxicosis.     

Thiamin supplementation and the ingestive behavior of beef cattle grazing endophyte-infected tall fescue

Livestock grazing endophyte (Acremonium coenophialum Morgan-Jones and Gams)-infected tall fescue (Festuca arundinacea Schreb.) perform poorly due to tall fescue toxicosis, especially when animals are under heat stress. In order to determine whether thiamin promotes recovery from tall fescue toxicosis, 1 or 0 g of thiamin per day, as mononitrate, was fed orally to adult Angus (Bos taurus) cows (380 +/- 8 kg) grazing either tall fescue pasture with and without endophyte or alfalfa (Medicago sativa L.). A tethered grazing system employing a split-plot design was used to estimate intake and components of ingestive behavior. No significant differences attributable to thiamin supplements were seen in rates of intake and biting, grazing time and intake per bite when cows grazed endophyte-infected tall fescue during the first 4 d of exposure. When cows grazed endophyte-infected (greater than 95%) tall fescue with 2,091 micrograms/g loline alkaloids after 4 d of exposure, the untreated animals ingested herbage dry matter (DM) at 1.19 kg/h, whereas the cows receiving thiamin ate 1.57 kg/h (P less than .05). Cattle achieved these rates of DM intake by forming bites of 1.0 and 1.2 g DM at 24 and 26 bites/min when treated with 0 and 1 g of thiamin per day, respectively. Thiamin supplements had no effect on ingestive behavior of cows grazing endophyte-free tall fescue or alfalfa after exposure to these forages for 4 d. Responses to thiamin generally were greater when cattle grazing endophyte-infected tall fescue were exposed to heat stress. Oral thiamin supplementation may alleviate tall fescue toxicosis of beef cattle during warm weather.     

Behavior, preference for, and use of alfalfa, tall fescue, white clover, and buffalograss by pregnant gilts in an outdoor production system

Sustainable outdoor pig production requires vegetation that can maintain ground cover, assimilate manure nutrients, and prevent soil erosion. Two experiments were conducted to evaluate the suitability of four forages: alfalfa (Medicago sativa), tall fescue (Festuca arundinacea), white clover (Trifolium repens), and buffalograss (Buchloe dactyloides) for grazing or ground cover in pastures for pigs. Each forage plot covered 7.5 m2, with nine replicates in a randomized block design. In Exp. 1, eight pregnant gilts had free access to all forages during a 2-d adjustment period. Immediately thereafter, pairs of gilts were assigned randomly to one of each of four blocks of the four forages during a 2-d measurement period. The percentage of ground cover for each forage was visually estimated at 0, 24, and 48 h of study. Behavioral data, including walking, eating, grazing, rooting, drinking, standing, lying, and time spent in hut were video-monitored continuously for 48 h. Initial percentage of ground cover was 100% for all species. By 48 h, percentage of ground cover decreased (P < 0.001) for white clover (11.3 +/- 0.88%) and alfalfa (36.3 +/- 0.88%), but not for tall fescue (98.0 +/- 0.88%) or buffalograss (98.0 +/- 0.88%). Gilts spent more (P < 0.01) time grazing white clover (16.3 +/- 1.97 min/d) and alfalfa (11.2 +/- 1.97) than tall fescue (0.8 +/- 1.97) or buffalograss (0.3 +/- 1.97), and rooted more (P < 0.04) white clover than other forages. In Exp. 2, six gilts from the initial group were put on six blocks of the four forages. Each gilt was assigned randomly to three replicates of each forage, including alfalfa, tall fescue, or buffalograss (white clover was excluded because of damage by gilts during Exp. 1), and gilts grazed single forages for 2 d. After this grazing period, the percentage of ground cover was less (P < 0.01) for alfalfa than for buffalograss or tall fescue (37.5 +/- 0.38, 96.7 +/- 0.39, 96.3 +/- 0.39%, respectively). With access to a single forage, pregnant gilts spent more (P < 0.01) time grazing alfalfa (15.8 +/- 2.36 min/d) than buffalograss (1.5 +/- 2.36) or tall fescue (0.7 +/- 2.37). These gilts clearly preferred grazing white clover and alfalfa, and rooting and eating white clover compared with buffalograss or tall fescue. Rates of ground cover loss were less (P < 0.01) for tall fescue and buffalograss than for the more preferred forages. Less preferred forages could have potential as pasture for swine when the primary objective is ground cover maintenance rather than nutrient supply.     

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.     

行间生草葡萄园土壤微生物量与土壤养分的通径分析

在酿酒葡萄(Vitis vinifera)园行间播种白三叶草(Trifolium repens L.)、紫花苜蓿(Medicago sativa L.)和高羊茅(Festuca arundinacea Schreb),以清耕为对照,研究了土壤微生物量、土壤微生物呼吸强度和土壤微生物熵的变化及其与土壤养分的关系。结果表明:与清耕(对照)相比,白三叶草和紫花苜蓿处理显著提高了土壤有机质、全氮含量,显著降低了速效磷含量;而高羊茅处理土壤有机质和速效钾含量显著低于清耕。白三叶草、紫花苜蓿和高羊茅处理土壤微生物量C含量分别比清耕增加65.2%,61.6%和6.7%;微生物量N含量分别比清耕增加53.6%,52.4%和15.0%。各生草处理土壤微生物熵均显著高于清耕,但土壤微生物呼吸强度与清耕之间无显著差异。微生物学指标总体与土壤有机质、全氮、碱解氮、速效钾呈显著或极显著正相关,与全磷和速效磷呈显著或极显著负相关。通径分析表明,碱解氮、全氮是影响土壤微生物量C、N和微生物呼吸强度、微生物熵重要的直接作用因子。     

补播禾草对退化苜蓿草地生产性能及牧草品质的影响

针对宁夏半干旱区7龄以上苜蓿(Medicago sativa)草地退化导致的牧草产量低、品质差等问题，本试验采用单因素随机区组设计，研究了多年生黑麦草(Lolium perenne)、披碱草(Elymus nutans)、苇状羊茅(Festuca arundinacea)、无芒雀麦(Bromus inermis)、鸭茅(Dactylis glomerata)补播对退化草地苜蓿主要农艺性状和牧草品质的影响，并利用主成分分析方法(PCA)评价其改良效果。结果表明：补播禾草对苜蓿株高、叶茎比、一级分枝数和干草产量均有显著影响(P<0.05)，其中，补播苇状羊茅干草产量最高，其次为多年生黑麦草和无芒雀麦；补播禾草对牧草粗蛋白、粗脂肪、粗灰分、中性洗涤纤维和酸性洗涤纤维含量有显著影响(P<0.05)；PCA分析得出，补播鸭茅、苇状羊茅综合性状分别排第一、二位。因此，可根据不同改良目的选择不同禾草种类进行补播，苇状羊茅可显著提高退化苜蓿草地生产性能，补播鸭茅可显著改善退化苜蓿草地牧草品质。     

紫花苜蓿对九种杂草的化感作用

试验运用生物测定法研究了紫花苜蓿叶化感物质对九种受体植物的作用.结果表明,紫花苜蓿叶提取物对多变小冠花的发芽势和发芽率具有抑制作用,与对照差异显著(P＜0.05);提取物对高羊茅种子的发芽势有促进作用,与对照差异显著(P＜0.05),其最终发芽率也增加(P＜0.05);除狗尾草外,其余八种受体植物的胚根长度都受到紫花苜蓿叶提取物的抑制,与对照的差异均显著(P＜0.05);提取物对稗草、狗尾草、高羊茅、毛马唐和多变小冠花的苗长具有促进作用,与对照差异均显著(P＜0.05);反枝苋的苗长则受到抑制(P＜0.05);提取物对受体植物的幼苗鲜重均有不同程度的影响,虎尾草、匍匐翦股颖、巴哈雀稗、反枝苋和多变小冠花幼苗鲜重明显降低,与对照差异达显著水平(P＜0.05).     

Behavior of steers grazing monocultures and binary mixtures of alfalfa and tall fescue.

Spectral analysis was used to relate dietary quality and herbage species to the behavior of grazing steers. Four .3-ha paddocks were established with either 'AU-Triumph' tall fescue (F; Festuca arundinacea Schreb.), 'Apollo' alfalfa (A; Medicago sativa L.), 1/3 fescue and 2/3 alfalfa (2/3A), or 2/3 fescue and 1/3 alfalfa (1/3A). Each paddock was stocked with 10 to 16 steers and defoliated in 5 d. Three steers on each paddock carried vibracorders to monitor grazing time. Daily forage samples were taken in 10-cm layers and weighed. Esophageal extrusa were collected from fistulated steers to measure diet quality. Daily grazing time did not differ (P = .37) among treatments; however, steers grazing mixtures grazed numerically longer (1.4 h/d) than steers on monocultures. Spectral analysis revealed that steers grazing A and 2/3A had many daily meals of short duration, but steers grazing 1/3A and F consumed three meals daily at 8-h intervals. Throughout the 4.67-d grazing period, quality of the diet linearly declined in crude protein and herbage digestibility, linearly increased in neutral detergent fiber and cellulose, and exhibited quadratic changes in lignin and ash. For most quality values, the tall fescue monoculture differed from the others (P < .05). Steers selected diets with similar quality for the A, 2/3A, and 1/3A treatments. This study illustrates how differences in forage diets alter grazing behavior of steers.     

几种重要饲草的阴阳离子平衡分析

优质饲草是奶牛高产健康的基础。为探讨优质饲草在围产期奶牛日粮中的重要性,对紫花苜蓿、苇状羊茅、鸭茅、无芒雀麦等12个饲草样品进行了钠、钾、氯、硫含量的测定并进行了阴阳离子差(CAD)分析。结果表明:(1)饲草Na 含量的变异幅度最大,K 和S2-居中,Cl-最为稳定。K 含量最高,其次为Cl-、S2-和Na 。K 含量对CAD值的影响最大。(2)苇状羊茅、无芒雀麦和鸭茅抽穗期的CAD低于孕穗期。紫花苜蓿初花期的CAD低于现蕾期和盛花期。饲草的收获期对CAD值有一定影响。     

苏南丘陵山区秋播紫花苜蓿伴播作物及其播量的筛选

为解决苏南丘陵区紫花苜蓿(Medicago sativaL.)苗期的杂草问题,选择多花黑麦草(Lolium multiflorum Lam.)、小黑麦(X Triticosecale Wittm.)、苇状羊茅(Festuca arundinacea Schreb.)3种作物作为紫花苜蓿的伴播作物,实施不同间、混作方式,通过测定分析产量、株高、杂草量等多个指标,筛选该地区适宜的紫花苜蓿伴播作物及其播量。综合表现较好的伴播组合为:16.7 kg/hm²紫花苜蓿+25.0 kg/hm²赣选一号多花黑麦草,撒播;16.7 kg/hm²紫花苜蓿+266.7 kg/hm²中新830小黑麦,紫花苜蓿行距40 cm条播,行间条播小黑麦。3种伴播作物对紫花苜蓿和杂草的抑制作用大小依次为"赣选一号"多花黑麦草>"中新830"小黑麦>苇状羊茅。