草地早熟禾农杆菌介导法基因转化条件

以大青山草地早熟禾(Poapratensis L.cv.Daqingshan)和超级伊克利草地早熟禾(PoapratensisL.cv.Totaleclipse)成熟种子诱导产生的胚性愈伤组织为材料,比较抗生素及筛选剂对愈伤组织生长和绿苗分化的影响.结果表明:500mg/L的羧苄青霉素或头孢霉素对愈伤组织的生长与对照间差异不显著;羧苄青霉素可提高愈伤组织绿苗分化率,而头孢霉素则有抑制作用;2个供试品种G-418的筛选浓度分别为50和70mg/L时,愈伤组织的褐化率达100%;在幼苗分化期,G-418浓度为20mg/L时,2个供试品种的试管苗均为白化苗;在观察到愈伤组织周围的培养基上显现菌落时,立即转移到筛选培养基上为宜.用农杆菌介导法获得了转苏云金芽孢杆菌杀虫晶体蛋白(B.t)基因植株.     

采用3种遗传标记技术对早熟禾属植物物种鉴定及系统学比较

采用3种不同的遗传标记技术对10种早熟禾属植物进行物种辅助鉴定，以形态学分类系统为基础对3种技术在早熟禾属种间亲缘关系研究中应用的可能性进行了比较和检验，结果表明：它们的共同特点是快速、简便和经济。POD、EST两种技术都可用于对早熟禾属物种的辅助鉴定，但POD技术在稳定性、酶带集中性和可操作性方面优于EST技术。RAPD技术无论是用于物种的鉴定还是种间亲缘关系的研究，其效果均好于前二者，而且它的系统聚类结果几乎与形态学分类结果完全一致。     

亚热带地区野生草地早熟禾夏季休眠特性研究

对4份草地早熟禾在亚热带地区的夏季休眠特性进行初步研究,结果表明:从生长速度、生物量、草坪质量等方面综合判断,不同草地早熟禾在夏季进入休眠的时间和程度不同,其中P07和PCK进入了完全休眠,休眠时间分别在7月27日和8月6日;P03仅进行了半休眠,时间为9月5日;P06在整个夏季都未进入休眠状态;休眠期草地早熟禾主要表现为:生长速度几乎停滞,生物量出现较大幅度程度的降低,草坪质量下降严重,并且出现较大的枯黄率;相关分析表明,生长速度、生物量、草坪质量是判断草地早熟禾夏季休眠的有效指标性特征.     

钾素改善干旱胁迫下早熟禾的形态及相关生长指标

本研究采用不同浓度钾素营养处理的方法,在干旱条件下,研究草地早熟禾(Poa pratensis)形态及生长相关指标与抗旱性间的关系,为草坪草早熟禾在生产中的利用及提高其抗旱能力提供理论依据和指导。结果表明,适当的供给钾素可以改善干旱胁迫引起的叶片形态改变,从而提高草地早熟禾的抗旱能力。在干旱胁迫下,草地早熟禾叶片形态、色泽及生物量在钾素浓度为0.15~0.30 g·kg~(-1)时有所改善和提高,其中0.30 g·kg~(-1)钾素浓度的处理效果最好,可明显提高早熟禾植株的抗旱性。     

9份甘肃野生驯化草地早熟禾种质的生产性能比较研究

为有效开发利用甘肃野生草地早熟禾种质资源,驯化筛选乡土草地早熟禾优良材料,在甘肃省不同生态区域采集草地早熟禾种质,经栽培驯化,筛选了9份优良材料,以康乐野生小药早熟禾(Poa micandra cv.Kangle)、青海扁茎草地早熟禾(Poa pratensisvar cv.Qinghai)为对照,在兰州进行了生产性能和营养价值的比较研究。结果表明:各供试材料均于3月初返青,返青率达92%,越冬表现好,其中天祝、安定、渭源和秦州草地早熟禾的生育期为69~82d,是早熟型材料,兴隆山、西和、夏河、清水和肃南草地早熟禾的生育期在90~98d,为晚熟型材料。应用灰色关联度进行综合评价,兴隆山、夏河、安定草地早熟禾在分蘖数、盖度、地上生物量鲜重、地上生物量干重及地下生物量干重5个性状的生态性能较好,是良好的生态型材料;清水、渭源、秦州草地早熟禾不仅以上5个性状表现好,且在叶茎比、粗蛋白及相对饲喂价值上也表现较好,是良好的生态兼牧草型材料。     

Effects of Ozone on Growth of Seven Grass and One Clover Species

Abstract

Seven species of grass and one of red clover were grown at different ozone (O₃) concentrations for about five weeks in growth chambers located in a greenhouse. At an O₃ concentration of 55 compared with 10 nmol mol^?1 during 7 h day^?1 the shoot dry weight decreased by 45% in Phleum pratense, 28% in Dactylis glomerata and Poa pratensis, 23% in Festuca rubra and 16% in Festuca pratensis, while the effects on Agrostis tenuis were not significant. No effect was found at 25 compared with 10 nmol mol^?1O₃. Visible O₃ injury was observed in all six species at 55 nmol mol^?1 and this effect was generally well correlated with the effect on the dry weights. In another experiment no effect was found with O₃ concentrations of up to 62 nmol mol_?1 on Lolium perénne, while the dry weight in Trifolium pratense decreased by 30% at 59 compared with that at 6 nmol mol^?1.     

Enhancing Seed Germination Rate of Four Turfgrass Genera by Acid Treatments

Turfgrasses are commonly propagated by seeds. In some genera of turfgrasses, the presence of low germination percentage (GP) or rate is the main problem in seed propagation. The present investigation was undertaken to determine the best concentration and duration of sulphuric acid treatment for seeds of the following turfgrass genera: Cynodon dactylon [L.] Pers.; Festuca rubra L. var. rubra‘Shadow’; Lolium perenne L. ‘Barball’ and Poa pratensis L. ‘Merion’. In the first experiment, sulphuric acid was used with concentrations of 0 (control), 25, 50, 75 and 100 % for 10, 15, 20, 25 and 30 min. In the second experiment, effects of light/dark (16/8) or dark conditions on germination rates of different mentioned genera were investigated using the best specific acid treatments. Each treatment was replicated four times with 100 seeds per replicate kept in plastic Petri dishes. The results indicated that in Cynodon, using 50 % acid for 20–25 min had highest GP and mean daily germination (MDG) in light/dark; in Festuca, using 25 % acid for 15 min had highest GP and MDG in light/dark; in Lolium using 50 % acid for 10 min had highest MDG in dark and in Poa, using 50 % acid for 15–25 min had highest MDG in dark. Both Cynodon and Poa had the highest and Festuca had the lowest GPs. Cynodon and Festuca had the highest and lowest MDGs, respectively. This simple procedure, with considerable results, may be replaced to time-consuming and expensive methods such as seed priming.     

开花期施磷对青海扁茎早熟禾种子产量及繁殖分配的影响

以5龄青海扁茎早熟禾(Poa pratensis var.anceps Gaud.cv.Qinghai)为研究对象,在开花期进行不同梯度磷添加试验,探讨施磷对其种子产量的影响.结果表明:通过开花期施磷,增加了穗干物质转运和穗部生物量,进而提高青海扁茎早熟禾种子产量(3％～28％).施磷量在60kg/hm2(P2)时,种...     

北京地区早熟禾褐斑病菌生物学特性及防治研究

对北京地区早熟禾褐斑病分离到的立枯丝核菌(Rhizoctonia solaniKuhn)进行了7个温度(12,16,20,24,28,32,36℃)、两种光照条件(全黑暗和12 h光暗交替)下的菌丝生长速率测定、菌核产生量比较,温度对发病的影响,10种杀菌剂的抑菌试验和几种杀菌剂的田间药效试验。菌丝生长的适宜温度范围为24~32℃;12 h光/暗交替条件下,菌丝生长速率加快;32℃下菌核产生量显著多于其他温度;20~30℃下早熟禾发病严重。多菌灵、扑海因、坪安1号和多氧霉素等杀菌剂的抑菌效果好。田间药效试验表明,扑海因、井岗霉素、坪安1号和多菌灵对褐斑病有良好的防治作用。     

Impacts of soil moisture level and organic matter content on growth of two Juncus species and Poa pratensis grown under acid soil conditions

The abundance of Juncus effusus (soft rush) and Juncus conglomeratus (compact rush) has increased in coastal grasslands in Norway over recent decades, and their spread has coincided with increased precipitation in the region. Especially in water‐saturated, peaty soils, it appears from field observations that productive grasses cannot compete effectively with such rapidly growing rush plants. In autumn–winters of 2012–2013 and 2013–2014, a four‐factor, randomised block greenhouse experiment was performed to investigate the effect of different soil moisture regimes and organic matter contents on competition between these rush species and smooth meadow‐grass (Poa pratensis). The rush species were grown in monoculture and in competition with the meadow‐grass, using the equivalent of full and half the recommended seed rate for the latter. After about three months, above‐ and below‐ground dry matter was measured. J. effusus had more vigorous growth, producing on average 23–40% greater biomass in both fractions than J. conglomeratus. The competitive ability of both rush species declined with decreasing soil moisture; at the lowest levels of soil moisture, growth reductions were up to 93% in J. conglomeratus and 74% in J. effusus. Increasing water level in peat–sand mixture decreased competivitiveness of meadow‐grass, while pure peat, when moist, completely impeded its below‐ground development. These results show that control of rush plants through management may only be achieved if basic soil limitations have been resolved.