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31.
何海锋  吴娜  刘吉利  许兴 《草业学报》2022,31(10):64-74
为了探究不同施磷水平对宁夏银北盐碱地区柳枝稷生长发育及耐盐性的影响,通过田间试验,以2种生态型柳枝稷品种“Alamo”和“Pathfinder”为供试材料,采用裂区试验设计,设置不施磷(0)、施低磷(30 kg·hm-2P2O5)和施高磷(90 kg·hm-2P2O5)共3个施磷水平,每个处理设3个重复,共计18个小区。分析比较了各生育时期内柳枝稷生长指标、渗透调节物质及抗氧化酶活性的变化,同时采用隶属函数法综合评价了盐碱地柳枝稷的耐盐性。结果表明,随着施磷水平的提高,两种生态型柳枝稷开花期株高、分蘖数、叶面积指数、干物质积累和生物产量等农艺性状和相对叶绿素、丙二醛、可溶性糖含量、过氧化物酶活性等生理特性均呈逐渐升高的总趋势。与不施磷处理相比,分别提高了7.74%、10.21%、14.64%、11.88%、22.22%、3.85%、74.29%、14.70%和57.77%。隶属函数分析结果表明,施低磷处理下柳枝稷各抗盐指标隶属函数值的均值最大。因此,施磷量...  相似文献   
32.
8份柳枝稷种质资源苗期抗旱性综合评价   总被引:2,自引:0,他引:2  
柳枝稷(Panicum virgatum)是重要的能源草之一,其苗期的耐旱能力是其能否在干旱、半干旱地区良好生长的关键。因此,鉴定并筛选出苗期耐旱的柳枝稷品种具有重要意义。本研究通过温室盆栽试验,对超氧化物歧化酶、过氧化物酶、游离脯氨酸、可溶性蛋白、可溶性糖、叶片含水量、相对电导率及丙二醛共8个耐旱相关的生理指标进行测定,并根据隶属函数法评价了选自美国基因库的8份柳枝稷材料的抗旱性。结果表明,8份柳枝稷材料在苗期的抗旱性各不相同,并且其抗旱性由大到小的排列顺序为ShawneeCave-in-RockBlackwellBN-309-69TrailblazerCarthageTEM-SLCGrenville。本研究结果可以为柳枝稷抗旱性育种提供理论依据,也可为其在边际土地上的推广应用提供科学的栽培管理依据。  相似文献   
33.
Abstract

General agreement does not exist as to the most appropriate method to estimate plant available Mn in soils. In the current investigation soil and soil solution Mn were measured in limed and unlimed treatments of 11 acidic subsoil horizons and related to plant Mn concentrations, Mn uptake and growth of subterranean clover (Trifolium subterraneum L. cv. Mt. Barker) and switchgrass (Panicum virgatum cv. Cave‐in‐Rock). Manganese measurements were taken at planting and harvest and included: Mn extracted by 1M NH4OAc (pH 7), 0.01M CaCl2, 0.05M CaCl2, 0.033M H3PO4, 0.005M DTPA, 0.2% hydroquinone in 1M NH4OAc (pH 7), 0.01M NH2 OH.HCl 4 2 in 0.01M HNO3, total soil solution Mn and concentrations and 2+ activities of Mn2+ calculated from the GEOCHEM program. Measured and calculated values of soil solution Mn generally gave the best correlations with subterranean clover and switchgrass Mn concentrations and Mn uptake. Root Mn concentrations were highly correlated with soil solution Mn measurements taken at harvest with r=0.97 and r=0.95 (p<0.01) for subterranean clover and switchgrass respectively. The Mn extracted by 0.01M CaCl was also significantly correlated (p<0.01) with plant Mn concentrations and Mn uptake and proved to be better than the other extractants in estimating plant available Mn. Although Mn concentrations as high as 1769 mg/kg (shoots) and 8489 rag/kg (roots) were found in subterranean clover, Mn did not appear to be the major factor limiting growth. Measures of soil and soil solution Mn were not strongly correlated with yield. Both Al toxicities and Ca deficiencies seemed to be more important than Mn toxicities in limiting growth of subterranean clover and switchgrass in these horizons.  相似文献   
34.
自然盐碱胁迫对柳枝稷生物质生产和燃料品质的影响   总被引:2,自引:0,他引:2  
在自然盐碱地条件下,研究了不同程度盐碱胁迫对柳枝稷生物质产量和品质的影响.结果表明:随着盐碱胁迫程度加重,柳枝稷成活率、株高、单株分蘖数和生物质产量、品质显著降低,盐碱胁迫程度对柳枝稷越冬率无显著影响.柳枝稷可在盐碱地环境下生长,成活率达85%以上,越冬率达96%以上,轻度和中度盐碱地柳枝稷的生长状况较好,产量最高达到14.3 t/hm2.盐碱胁迫增加了柳枝稷生物质中的灰分与木质素含量,降低了生物质热值、纤维素和半纤维素含量,在一定程度上降低了柳枝稷生物质的品质.  相似文献   
35.
Three grass species, switchgrass ( Panicum virgatum ), foxtail millet ( Setaria italica ), and Old World bluestem ( Bothriochloa ischaemum ), referred to as introduced, traditional, and indigenous species, respectively, in the Loess hilly gully region on Loess Plateau in China, were grown in a growth chamber. Water was withheld to let the soil gravimetric moisture content (SGMC) decline gradually from 14.92% for 15 days. The gas exchange characteristics, leaf water conditions, root and shoot growth, and water use efficiency (WUE) of the three grasses were compared. The SGMC of foxtail millet declined faster than that of switchgrass and Old World bluestem, and it maintained higher leaf water potential at a lower soil water content, indicating that it might have greater drought tolerance. During the process of soil drying, the stomatal conductance (Gs), photosynthesis rate, and transpiration rate (Tr) of foxtail millet and Old World bluestem declined linearly, whereas those of switchgrass declined parabolically. The Gs of each grass was significantly different between the stressed and well-watered (WW) conditions. When the SGMC declined to ≈ 11.0%, 9.5%, and 8.6%, respectively, the leaf water potential was significantly different between the two growing conditions, showing the appearance of non-hydraulic and hydraulic signals. As a result of greater stomatal adjustment ability and a smaller Gs, foxtail millet had a high WUE. Among the three grasses, switchgrass had a high Tr and root/shoot (R/S) ratio under both WW and stressed conditions, and water stress significantly improved its R/S ratio. The results showed that foxtail millet seedlings have the best drought adaptability in the flexible soil–water environment, whereas switchgrass seedlings have the worst, but a high R/S ratio might be advantageous under drought conditions once the seedlings are established.  相似文献   
36.
Switchgrass (Panicum virgatum L.) is a model bioenergy species with a high biomass production from which renewable sources of fuel and electricity can be generated. The objective of this study was to perform divergent single-plant selection for biomass yield at low plant density, intermate the selected plants in polycrosses, and evaluate the performance of their half-sib (HS) progenies in sward and row plots. One thousand plants from Alamo and Kanlow populations were planted in unreplicated honeycomb trials with a plant spacing of 120 cm. Moving-ring selection was applied to select 15 high- and 15 low-yielding plants from each population. These were grown in separate polycrosses to create HS-families. Four HS-families from high- and 4 from low-yielding parents of Alamo and Kanlow, along with their bulks were evaluated for 3 years in sward plots with row spacing of 18 cm. Five HS-families from high- and five from low-yielding parents of Alamo and Kanlow were evaluated for 2 years in row plots spaced 76 cm along with their bulks. Overall, the row-plots had 20% higher biomass per unit area than the sward-plots. Across populations and plant densities, the highest-yielding HS-families produced between 2.0 and 9.3 t/ha more biomass than the lowest-yielding HS-families. The mean biomass of the HS-families from parents selected for high-yield was between 0.34 and 4 t/ha higher than the mean of the HS-families from the low-yielding parents. The annual response to selection for the mean and the bulk of the HS-families from the high yielding parents was 19 and 27% higher than the check. These results indicate that on average, high- and low-yielding parental genotypes were effectively selected from the two populations under low plant density.  相似文献   
37.
ABSTRACT

Parallel to the growing interest in switchgrass (Panicum virgatum L.) in southern countries of Europe, there is enhanced interest in knowing about its potential adaptability in the European regions with cool and moderate climates. The objective of this work was to characterize important agricultural parameters of switchgrass originated from North Dakota in order to identify the most valuable accessions for further research, propagation, and breeding in the Nemoral zone of Europe. The selection aimed at evaluating overwintering and productivity of switchgrass, with the ultimate objective of biomass quality improvement. Field trials were carried out in the central lowland of Lithuania during 2012–2014 on 33 germplasm accessions of switchgrass originating from North Dakota. Allthe tested accessions exhibited almost similar overwinter survival rate, i.e., 93.7–96.7%. Significant differences were observed in mean dry matter yields of all the tested accessions harvested once or twice per season (P < 0.05). The higher yielding accessions during both study years were differentiated. The yield potential of these accessions depended on a number of morphological traits, including internode thickness, plant height, panicle length, and leaf and stem weight per tiller (P < 0.05). Ash and mineral composition was associated with the genotype and the year of biomass harvest (P < 0.05). The switchgrass genotypes originating from North Dakota appeared to be adaptable to the European environment with cool and moderate climate and short growing season. The best-performing accessions can serve as a valuable genetic source for future breeding programmes.  相似文献   
38.
采用纤维素复合酶直接酶解(Direct enzymolysis,DE)、1% H2SO4预处理后酶解(Enzymolysis after 1% H2SO4 pretreatment,ACE)和1%NaOH预处理后酶解(Enzymolysis after 1% NaOH pretreatment,ALE)3种处理方法对2种生态型柳枝稷Alamo(低地型)和Cave-in-Rock(高地型)茎秆进行降解效率的研究,并对其细胞壁组成特点进行分析。结果表明:1)DE处理下,Alamo茎秆总产糖效率、六碳糖产糖效率和纤维素降解效率分别显著高于Cave-in-Rock 24.94%、40.52%和24.68%(P0.05或0.01);ACE处理下,Alamo茎秆预处理产糖效率、酶解产糖效率和总产糖效率分别显著高于Cave-in-Rock 17.13%、25.69%和16.87%,五碳糖产糖效率、六碳糖产糖效率和纤维素降解效率分别显著高于Cave-in-Rock 9.71%、38.93%和21.86%;ALE处理下,Alamo茎秆酶解产糖效率和总产糖效率分别显著高于Cave-in-Rock 16.69%和13.48%,五碳糖产糖效率、六碳糖产糖效率和纤维素降解效率分别显著高于Cave-in-Rock 13.07%、17.46%和6.59%;2)Alamo茎秆细胞壁中纤维素含量显著高于Cavein-Rock 11.31%,纤维素结晶度和聚合度分别显著低10.09%和40.54%;半纤维素中阿拉伯糖(Ara)含量显著高于Cave-in-Rock 5.28%,而木糖(Xyl)含量显著低于Cave-in-Rock 1.37%,阿拉伯糖替代程度(Ara/Xyl)显著高于Cave-in-Rock 6.74%;木质素单体紫丁香基(S)含量显著高于Cave-in-Rock 16.40%。较高的纤维素含量、较低的纤维素结晶度和聚合度是Alamo茎秆高产糖效率的直接原因,推测阿拉伯糖的替代程度对纤维素结晶度和聚合度的影响以及较高含量的木质素单体S可能是Alamo茎秆高降解效率的深层次原因。  相似文献   
39.
14份柳枝稷种质资源苗期耐镉性综合评价   总被引:2,自引:0,他引:2  
镉(Cd)是环境中常见的非生物胁迫因子,从种质资源中筛选出不同耐镉型的植物材料有利于能源植物在重金属污染土地上的高效开发利用。基于此,本研究以14个能源植物柳枝稷品种为供试材料,外源施加浓度为10 μmol·L-1镉,结合形态和生理指标,采用隶属函数及标准差系数权重法综合评价了柳枝稷幼苗对Cd的耐受性。结果表明:10 μmol·L-1 Cd胁迫显著降低了柳枝稷根长、根表面积、根尖数、总生物量、净光合速率及根系活力,且品种间差异显著(P<0.01)。根据隶属函数法得到柳枝稷对镉耐受性综合评价值(D),其中Kanlow最高,Forestburg最低。采用系统聚类法对D值进行聚类分析,结果表明,14份柳枝稷可分为3组不同耐镉型材料,其中强耐镉型材料1份,为Kanlow;中等耐镉型材料9份,分别为Alamo、BoMaster、Carthage、Cave in Rock、Longisland、Newyork、Shawnee、Sunburst、Trailblazer;镉敏感型材料4份,分别为Blackwell、Dacotah、Forestburg、Shelter。结合柳枝稷对Cd的吸收,进一步分析发现耐镉性较强的品种镉富集能力也较强。可为选择适宜的柳枝稷材料种植于镉污染土地上提供理论依据,同时为丰富评价植物耐镉种质资源提供可操作性的方法。  相似文献   
40.
以柳枝稷品系‘西稷1号’、‘西稷2号’和‘西稷3号’为主区,以农杆菌菌液浓度为副区,对农杆菌浸种处理后柳枝稷种子萌发及幼苗生长发育相关性状进行了研究。结果表明,品系与农杆菌菌液浓度的互作效应不显著;不同基因型品系对农杆菌的敏感程度不同,其中西稷3号最不敏感;随着农杆菌菌液浓度的升高,柳枝稷种子发芽率、幼苗成苗率及叶绿素含量呈下降趋势,幼苗POD活性、CAT活性、MDA含量呈上升趋势,SOD活性呈先升后降的趋势。综合农杆菌对柳枝稷种子萌发及幼苗生理生化特性影响,在柳枝稷农杆菌浸种转化法中菌液浓度控制在1.2 OD600较为适宜。  相似文献   
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