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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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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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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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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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模拟干旱胁迫下镁对高羊茅种子萌发的影响 总被引：1，自引：0，他引：1
采用PEG-6000(100,200,300g/L)模拟水分胁迫,研究不同浓度的硫酸镁溶液(0.2,0.4,0.6,0.8g/L)浸种对高羊茅(Festuca arundinacea)种子萌发的影响。结果表明:随着干旱胁迫程度的增加,高羊茅的发芽率,发芽指数,苗长,根长,幼苗鲜重及根鲜重等指标均呈下降趋势。在种子萌发阶段,轻度干旱胁迫(PEG=100g/L)下,硫酸镁浸种对高羊茅种子的萌发促进作用不明显,其发芽率、发芽势、发芽指数与对照差异不显著;中度干旱胁迫(PEG=200g/L)下,0.6g/L的镁使得高羊茅种子的萌发相对最佳,其发芽等指标与对照差异显著(P0.05);重度干旱胁迫下(PEG=300g/L),0.4g/L镁处理明显的促进了高羊茅种子的萌发,其发芽指标与对照差异显著(P0.05),而当镁浓度是0.8g/L时,则抑制了高羊茅种子的萌发。在幼苗的生长前期,轻度干旱和中度干旱胁迫下,0.6g/L镁处理对高羊茅的苗长、根长、幼苗鲜重及根鲜重等生长指标有显著的促进作用;重度干旱胁迫下,0.4g/L和0.6g/L的镁处理使其生长指标高于对照且差异显著(P0.05)。 相似文献
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铅胁迫下转DREB1A高羊茅对铅的吸收与耐受性研究 总被引：2，自引：0，他引：2
通过水培试验,研究转DREB1A高羊茅对铅的吸收与耐受性。分别用浓度为100 mg/L、200 mg/L、500 mg/L、1000 mg/L、1500 mg/L、2000 mg/L的铅溶液对生长1个月的高羊茅进行胁迫处理,3周后测算了高羊茅植株的铅含量、枯黄率、根系耐性指数、迁移率、富集系数、转运系数等指标。结果显示,相同的铅胁迫条件下,转基因高羊茅的生长状况较好,对铅的富集与转运能力也较强。但无论是在生长状况方面还是在铅含量及分布方面,两种高羊茅对铅胁迫的反应趋势基本相同。表明DREB1A基因未改变高羊茅对铅的转移运输机制,但提高了高羊茅对铅的富集能力及耐性,转DREB1A高羊茅可成为修复铅污染土壤的备选植物。 相似文献
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The objective of this study was to compare methane emission by goats consuming the condensed tannin-containing forage sericea lespedeza (Les-pedeza cuneata) or a mixture of crabgrass (Digitaria ischaemum) and Kentucky 31 tall fescue (Festuca arundinacea). Two groups of 12 Angora does (initial average BW = 41.5 +/- 2.7 kg) that previously grazed a pasture of sericea lespedeza or crabgrass/tall fescue for approximately 4 mo were used. After 1 wk of adaptation to metabolism cages, gas exchange was measured for 24 h in an open-circuit respiration calorimetry system with four head boxes. Forage harvested daily from the previously grazed pastures was consumed ad libitum. Crude protein concentration was 10.3 and 13.0%, IVDMD was 64.5 and 75.3%, and the level of condensed tannins was 17.7 and 0.5% for sericea lespedeza and crabgrass/tall fescue, respectively. Dry matter intake (1.11 vs. 0.67 kg/d) and digestible DMI (estimated from IVDMD; 0.71 vs. 0.51 kg/d) were greater (P < 0.01) for sericea lespedeza than for crabgrass/tall fescue. Ruminal ammonia N (3.7 and 9.9 mg/dL; P < 0.001) and plasma urea-N concentrations (16.7 and 20.9 mg/dL; P = 0.07) were lower for sericea lespedeza than for crabgrass/tall fescue. Concentrations of individual and total VFA and the acetate-to-propionate ratio in ruminal fluid did not differ between treatments (P > 0.19). Despite higher DMI by goats fed sericea lespedeza, daily energy expenditure (409 vs. 431 kJ/kg BW(0.75)), heart rate (70 vs. 73 beats/min), and the ratio of energy expenditure to heart rate (5.82 vs. 5.94) did not differ between sericea lespedeza and crabgrass/tall fescue, respectively (P > 0.13). Methane emission expressed as both quantity per day or relative to DMI was lower (P <0.001) for sericea lespedeza than for crabgrass/tall fescue (7.4 vs. 10.6 g/d and 6.9 vs. 16.2 g/kg DMI). Substantial differences between the forages in condensed tannins concentration and methane emission by Angora goats suggest that condensed tannins decreased methane emission. 相似文献
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海盐胁迫对苇状羊茅和多花黑麦草种子发芽的影响 总被引：11，自引：2，他引：9
用不同浓度的海盐溶液处理,研究了苇状羊茅Festuca arundinacea和多花黑麦草Lolium multiflorum种子在发芽阶段对海盐胁迫的反应.结果表明,海盐浓度低于6.4 g/L时,2种牧草种子的发芽不受影响;随海盐处理浓度增高,种子发芽率和种子活力指数逐渐下降.2种牧草相比,多花黑麦草种子发芽阶段对海盐的耐受性高于苇状羊茅.苇状羊茅和多花黑麦草种子发芽率降至50%的农业盐渍临界值的海盐浓度分别为19.98和22.78g/L. 相似文献
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L M Lauriault C T Dougherty N W Bradley P L Cornelius 《Journal of animal science》1990,68(5):1245-1253
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. 相似文献
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不同盐生境下硅对高羊茅生物量及生理生化特征的影响 总被引：1，自引：0，他引：1
利用水培实验研究了不同盐生境下硅对高羊茅幼苗生物量及生理生化特征的影响。研究结果表明,高羊茅幼苗生物量随着盐浓度增加而逐渐降低,200 mmol/L的盐浓度为高羊茅幼苗的临界盐浓度,盐浓度小于该临界值时,添加硅显著增加了高羊茅幼苗生物量;盐浓度大于该临界值时,硅对高羊茅幼苗生物量没有明显影响,说明硅调节盐生境下高羊茅的生长能力与环境内的盐浓度密切相关。在盐浓度临界值之内,水培条件下硅通过增加盐胁迫下高羊茅幼苗体内SOD、CAT、POD活性,降低盐胁迫条件下高羊茅幼苗体内的丙二醛、脯氨酸、可溶性糖含量和相对电导率,其中盐浓度为100 mmol/L时,丙二醛含量降幅最大,为18.05%,当盐浓度为50 mmol/L时,脯氨酸含量降幅最大,为23.63%。这不仅说明了硅可增强高羊茅幼苗适应盐生境的能力,而且证明了硅直接参与了盐胁迫条件下高羊茅的生理生化过程。 相似文献
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为探明CO2浓度对高羊茅(Festuca arundinacea)抗旱性及水分利用效率的影响机制,通过控制土壤水分及大气CO2浓度条件获得不同生境中高羊茅的生理光合参数,利用对比和统计分析的方法研究高羊茅的生理特征变化,并对影响高羊茅水分利用效率、蒸腾速率、净光合速率变动的主要环境因子进行了甄别与分析。结果表明:高大气CO2浓度对干旱胁迫给高羊茅带来的负效应具有补偿作用,可提高高羊茅的抗旱性;在高大气CO2浓度和干旱胁迫的交互作用下,影响高羊茅水分利用效率的主要环境因子是大气CO2浓度,而该效应产生的主要原因是蒸腾作用的减弱;高羊茅的净光合速率及蒸腾速率主要受气孔导度等限制因素的影响。在高大气CO2浓度和干旱胁迫交互作用时,蒸腾速率与气孔导度成线性关系,且R2超过0.97;而净光合速率除受气孔导度影响外,还与叶绿素含量及胞间CO2浓度关系显著,是多种因素综合作用的结果。 相似文献
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多效唑对高羊茅扩展性和根系特性的调控效应 总被引：3，自引：2，他引：1
在盆栽条件下,研究了喷施多效唑对高羊茅Festuca arundinacea单株扩展性和根系生态特性的影响,结果表明：在1001 900 mg/L质量浓度范围内,多效唑能有效抑制高羊茅植株的生长速度、地上枝叶的水平扩展、地上植物量的积累和根系生长,提高根系的表面积、体积和根冠比,促进分蘖和地下植物量的积累,质量浓度越高,调控效应越明显。质量浓度大于1 000 mg/L时,对分蘖的影响趋缓;大于1 300 mg/L时,对地上最大扩展距离、覆盖面积和地上植物量的影响趋缓。质量浓度为1 300 mg/L时,地下植物量、根系体积最大,根冠比最高。 相似文献
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水杨酸浸种对高羊茅在干旱胁迫下萌发的影响 总被引：2，自引：1，他引：1
用不同浓度水杨酸溶液浸泡处理冷季型草坪草高羊茅（Festuca arundinacea）的种子,在PEG 2000模拟干旱胁迫条件下,采用纸上发芽法（TP）研究了水杨酸浸种对盆景2000、猎狗5号、红宝石3个高羊茅品种萌发的影响。结果表明,在干旱条件下,适宜低浓度水杨酸溶液0.12~1.00 mmol/L浸种可以提高高羊茅种子的发芽势、发芽率,促进种子胚芽和胚根的生长,提高高羊茅种子萌发期的抗旱性;而高浓度水杨酸浸种抑制了种子的萌发和生长,3.00 mmol/L达到显著抑制水平（P＜0.05）。其中,能显著增强高羊茅种子萌发阶段抗旱性的水杨酸最适浓度为0.50 mmol/L。 相似文献
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C T Dougherty L M Lauriault N W Bradley N Gay P L Cornelius 《Journal of animal science》1991,69(3):1008-1018
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. 相似文献