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1.
京郊边际土地纤维素类能源草规模化种植与管理技术   总被引:2,自引:0,他引:2  
为探索能源植物在北京及周边地区的发展潜力,在京郊挖沙废弃地、荒滩地、撂荒地、污染农田4种边际土地上开展了柳枝稷、荻、芦竹和杂交狼尾草4种纤维素类能源草的规模化种植。在此基础上,总结提出了京郊边际土地纤维素类能源草规模化种植与管理技术,为基于边际土地发展京郊生物质原料生产与生物质能源产业奠定了良好的技术基础。  相似文献   
2.
NaCl胁迫对不同柳枝稷材料种子萌发与幼苗生长的影响   总被引:1,自引:1,他引:0  
杜菲  陈新  杨春华  张蕴薇 《草地学报》2011,19(6):1018-1024
采用不同浓度NaCl溶液对10份柳枝稷(Panicum virgatum)材料(其中5份为育成品种,5份为不同地理来源的野生种质)种子和幼苗进行胁迫处理,通过分析种子发芽率和幼苗株高、鲜重、脯氨酸含量、叶绿素含量、细胞膜透性的变化,研究其种子和幼苗对盐胁迫的反馈机制,分析不同材料的耐盐性水平,为柳枝稷的引种、育种工作提供参考。结果表明:随着NaCl浓度增加,柳枝稷发芽率、株高、鲜重、叶绿素含量下降,而脯氨酸含量、细胞膜透性增加。品种中,Cave-in-rock,Sunburst和Pathfinder耐盐性相对较强;地方野生种质播种期耐盐性较差,苗期耐盐性良好,具有较好的研发潜力。  相似文献   
3.
引种牧草柳枝稷对生菜化感作用初探   总被引:1,自引:0,他引:1  
以4种高地品种柳枝稷(Panicum virgatumL.)Pathfinder、Forestberg、Nebraska 28、Dakota为研究材料,采用室内皿培的生物测试方法,利用甲醇和蒸馏水浸提柳枝稷根系和地上部,通过分析浸提液对受体生菜种子胚根、胚芽长及发芽率的影响来鉴定柳枝稷化感潜势。结果表明,4种供试柳枝稷中Nebraska 28对生菜化感最强,而Pathfinder化感作用最弱,Forestberg与Dakota差异不明显;Pathfinder与其他3种柳枝稷不同,根系化感作用强于地上部;浸提液经过稀释后其甲醇浸提液化感作用强于蒸馏水浸提液;高质量浓度浸提液对生菜胚根生长影响较大,而低质量浓度对胚芽的化感作用较大。  相似文献   
4.
Life cycle assessment (LCA) can be an objective, strategic and immediate criteria in determining, case-by-case, the most suitable crop for energy. In this study, a cradle-to-farm gate LCA study was performed in 4 perennial energy crops and then compared to the environmental impacts of a conventional wheat–maize rotation. The functional units energy and hectare were used for ranking the crops. The results showed clear and constant environmental benefits, on average 50% lower impacts, by substituting the conventional rotation with perennial crops. Among the latter, little differences were found on hectare basis, while the differences were strictly dependent on biomass yield, on energy basis. Giant reed, the most productive crop, showed at this regard the best performance, while cynara resulted in the lowest ecological benefits. A similar trend was also registered as concern the energy gain and efficiency that ranged from 75 (cynara) to 349 (giant reed) GJ ha−1, and from 7 to 30 (same order), respectively. On hectare basis, switchgrass achieved better results in six categories out of nine, and especially, it was from 27% to 32% less impacting than the other perennials on marine water ecotoxicity, which resulted in the clearly most affected category after normalisation on average European inhabitants. Weighting is not allowed for public comparison (ISO 14042), yet it can be helpful for some overall indications and conclusive comments. Comparing giant reed and switchgrass under different weighting sets, it emerged that resource depletion was the main discriminator for crop choice. Evenly weighting human health (HH), resource depletion (RD) and ecosystem quality (EQ) categories made the preference toward switchgrass or giant reed very uncertain. Taking three different weighting sets with RD, HH and EQ having 50% of relative importance (25% was set for the remaining two categories), switchgrass appeared the best choice in two cases (i.e. HH = 50% and EQ = 50%) out of three. Therefore, the preference toward a specific energy crop will strongly depend on weighting sets that may considerably change in space and time.  相似文献   
5.
柳枝稷(Panicum virgatum L.)存在苗期生长缓慢的现象,而菌根真菌与植物共生可以促进植物生长。为了探究菌根真菌对柳枝稷苗期生长的影响,我们以来自于柳枝稷低地型品种Alamo的2个品系Ma和Mg为材料,诱导丛枝菌根真菌(Arbuscular mycorrhizal fungi,AMF)与柳枝稷共生,研究丛枝菌根真菌对柳枝稷苗期生长的影响及其分子机制。结果表明:丛枝菌根真菌可以侵入苗期柳枝稷根的内部形成共生菌根,并显著增加柳枝稷苗期的叶绿素含量、株高、叶片数和生物量。寄生植物瓜列当(Orobanche aegyptiaca)种子萌发和独脚金内酯(Strigolactones,SLs)合成标记基因检测实验表明,丛枝菌根真菌与柳枝稷共生可以抑制柳枝稷根系合成独脚金内酯,进而解除独脚金内酯对柳枝稷分蘖的抑制作用,促进柳枝稷苗期的生长。  相似文献   
6.
氮磷钾肥对能源草柳枝稷苗期生长的影响   总被引:2,自引:2,他引:0  
为了探索柳枝稷在边际土地规模化种植过程中肥料效应方面的基础数据,在日光温室内开展了沙土盆栽柳枝稷苗期氮磷钾肥料效应试验研究。结果表明,氮磷钾肥对沙土盆栽柳枝稷苗期的叶面积、株高、地上生物量、地下生物量、总生物量均具有明显的促进作用,而且,氮磷钾的单因素肥料效应均达到显著水平(P<0.05);柳枝稷苗期总生物量与氮磷钾之间存在着显著的三元二次回归关系,日光温室沙土盆栽条件下,获得柳枝稷苗期最高生物量所需要的适宜氮磷钾浓度分别为:氮(N)94.01mg/kg,磷(P2O5)40.18mg/kg,钾(K2O)117.96mg/kg。  相似文献   
7.
<正>柳枝稷(Panicum virgatum)属禾本科(Gramineae)黍属(Panicum)是多年生C4草本植物。该植物原产于北美,环境适应性极强,具有耐旱、耐盐碱、耐贫瘠等特点。它不仅是国际上公认的作为生物燃料的能源作物,还是一种优质牧草。截止2010年,柳枝稷在我国北方种植面积已达115.8 hm~2[1]。随着种植面积的不断扩大,柳枝稷病害问题越来越严重,病害造成柳枝稷生物量下  相似文献   
8.
No information is available on the effects of different biomass yield environments on selection efficiency in switchgrass (Panicum virgatum L.) breeding improvement. This study was conducted to assess the effects of high- and low-biomass yield environments (HYE and LYE, respectively) on recurrent selection for general combining ability (RSGCA) in a lowland population of switchgrass (NL-94). The top 14 of 65 NL-94 C0 parent plants were selected based on biomass yield of half-sib (HS) progeny tested for one post-establishment year under HYE and LYE conditions. Nine of the 14 C0 parent plants were the same based on HS performance under HYE and LYE. Selected plants were intercrossed to produce NL-94 HYE and NL-94 LYE C1 populations. One hundred and twenty-five HS C1 progeny families (60 NL-94 HYE and 65 NL-94 LYE) were evaluated for biomass yield for 3 years (2002–2004) under HYE and LYE conditions. The HYE produced about 2.5 times higher biomass yields than the LYE in both C0 and C1 HS progeny tests. Estimated additive genetic variance and predicted gains from selection (ΔG) were high in the C1 populations indicating that RSGCA should achieve higher biomass yields. Mean biomass yields of C1 HS families originating from the LYE protocol were significantly higher than those of families originating from the HYE protocol in both HYE and LYE performance tests, suggesting greater selection response under LYE in the C0 population. The estimates of narrow-sense heritability ( ) and ΔG from the C1 populations indicate that positive response to selection for biomass yield is possible in subsequent cycles of selection under either HYE or LYE, with a possible small advantage for HYE.  相似文献   
9.
以陕西定边县引种的8个柳枝稷(Panicum virgatum L.)品种(Blackwell,Cave-in-Rock,Dakota,Forest-berg,Illinois USA,Nebraska 28,Pathfinder和Sunburst)及行间杂草作为研究对象,通过计算柳枝稷对杂草的抑制率(RI),分析其生长指标与杂草生长指标的相关关系,判定不同柳枝稷品种在不同生育期对杂草生长的抑制效应,为其引种及田间杂草管理提供依据。结果表明:在生长初期(6月30日),Illinois USA杂草抑制率仅为3.4%,Cave-in-Rock和Forestberg对杂草生长抑制率分别为86.0%和74.9%;经过2次人工除草后(8月30日),Cave-in-Rock和Forestberg的杂草抑制率分别为85.7%和95.7%;生长后期(10月13日),仅Cave-in-Rock对杂草生长有88.5%的抑制率。回归分析显示,生长中后期(8月30日),柳枝稷地上部及根系生物量显著影响对杂草的抑制率(R2=0.31,0.54;P<0.05)。Pearson相关分析发现,Cave-in-Rock的株高、地上及根系生物量均显著降低杂草单株生物量(r=-0.97,-0.99,-0.99;P<0.05);Forestberg的植高与杂草密度显著负相关(r=-0.97,P<0.05)。  相似文献   
10.
为了开发利用黄河三角洲盐碱地和丰富该地区的牧草种质资源,本研究在黄河三角洲盐碱地开展了柳枝稷引种试验,对柳枝稷在该地区的育苗、田间移栽和后期管护等进行了详细阐述.结果表明,柳枝稷育苗出苗率高,苗期移栽成活率高,均达到90%以上;2年试验过程中,柳枝稷鲜草和种子产量最高分别达到7350 kg/hm2和203 kg/hm2,表明柳枝稷产量高,耐寒、耐盐碱能力较强,可在黄河三角洲盐碱地规模化种植推广.  相似文献   
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