Phenotypic plasticity of Artemisia ordosica seedlings in response to different levels of calcium carbonate in soil

Plant phenotypic plasticity is a common feature that is crucial for explaining interspecific competition, dynamics and biological evolution of plant communities. In this study, we tested the effects of soil CaCO_3(calcium carbonate) on the phenotypic plasticity of a psammophyte, Artemisia ordosica, an important plant species on sandy lands in arid and semi-arid areas of China, by performing pot experiments under different CaCO_3 contents with a two-factor randomized block design and two orthogonal designs. We analyzed the growth responses(including plant height, root length, shoot-leaf biomass and root biomass) of A. ordosica seedlings to different soil CaCO_3 contents. The results revealed that, with a greater soil CaCO_3 content, A. ordosica seedlings gradually grew more slowly, with their relative growth rates of plant height, root length, shoot-leaf biomass and root biomass all decreasing significantly. Root N/P ratios showed significant negative correlations with the relative growth rates of plant height, shoot-leaf biomass and root length of A. ordosica seedlings; however, the relative growth rate of root length increased significantly with the root P concentration increased, showing a positive correlation. These results demonstrate that soil CaCO_3 reduces the local P availability in soil, which produces a non-adaptive phenotypic plasticity to A. ordosica seedlings. This study should prove useful for planning and promoting the restoration of damaged/degraded vegetation in arid and semi-arid areas of China.     

猪毛蒿精油光活化抑制稗草生长及作用机理

采用小杯法,测定猪毛蒿精油在0．1～10．0mg／L质量浓度范围内,对稗草光活化抑制根、茎伸长的效果．结果表明：光照与非光照猪毛蒿精油均表现对稗草根伸长的抑制活性,光照显示更强抑制效果,特别对茎长的抑制活性更为显著．利用生化酶学方法,测定精油对稗草细胞保护酶活力的影响．结果表明：在0．1～10．0mg/L浓度范围内,猪毛蒿精油能诱导激活GST、GStt-Px和POD,而且光照可显著提高3种酶的活力．但对SOD则具有抑制活性．电镜观察,猪毛蒿精油可引起稗草愈伤组织细胞结构的严重损伤．     

封育对沙地油蒿群落生物量及其土壤水分影响

以毛乌素沙地东北部的油蒿群落为研究对象,对封育和未封育区的油蒿群落进行比较研究,结果表明:封育增加了群落的盖度,封育区群落盖度较未封育区提高了26％;封育区与未封育区油蒿群落生物量间存在显著差异,封育可以明显提高油蒿群落的生物量,但却降低了油蒿个体的生物量;土壤水分方差分析表明,封育区与未封育区土壤水分间差异不显著。     

沙蒿籽胶与黄原胶混合体系流变特性的研究

研究了沙蒿籽胶与黄原胶混合体系的流变特性。结果表明,沙蒿籽胶与黄原胶具有协同增效性,不同配比的沙蒿籽胶与黄原胶混合后,其协同增效性不同,当沙蒿籽胶与黄原胶的质量比6∶4时,二者的协同增效性最高,且胶溶液符合Herschel-Bu lkey流动模型,并具有胶变性。动态流变学特性表明:混合胶溶液显示弱凝胶特性。     

猪毛蒿枯落物水浸提液对5种草地植物种子萌发的化感作用

通过研究黄土高原撂荒农田优势植物猪毛蒿(Artemisiascoparia)枯落物水浸提液对5种草种子萌发的化感作用,以期为黄土高原撂荒地人工草地的建植及杂草防治提供一定的科学依据.结果表明,随着猪毛蒿枯落物水浸提液浓度的增大,受试草种测定指标有所差异,多年生黑麦草(Lolium perenne)、红豆草(Onobr ...     

打破野生藏沙蒿种子休眠方法的筛选与评价

为筛选能够打破野生藏沙蒿（Artemisia wellbyi）种子休眠的适宜方法，本研究采用不同温度的温水浸种，不同浓度硝酸钾（KNO₃）、赤霉素（GA₃）、吲哚乙酸（IAA）、微量元素浸种以及不同浓度过氧化氢（H₂O₂）、聚乙二醇（PEG-6000）浸泡滤纸等7种方法处理藏沙蒿种子，测定种子萌发及活力指标，并利用隶属函数法将各指标进行综合评价。结果表明：随着KNO₃浓度的升高，藏沙蒿种子的相对发芽率呈现升高的趋势；且高浓度KNO₃对藏沙蒿种子根的伸长有较高促进作用；低浓度的GA₃，IAA，PEG-6000和30℃温水浸种对藏沙蒿种子萌发有促进效果；微量元素浸种对藏沙蒿种子的萌发影响较对照差异不显著；较高H₂O₂浓度下藏沙蒿发芽指数有所升高，但对其根长和芽长有一定抑制作用。综合分析，不同浓度GA₃，10 mg·L^-1IAA浸种处理12 h对藏沙蒿种子的萌发促进效果整体最优，可以作为打破藏沙蒿种子休眠的适宜方法。     

Wind-proof and sand-fixing effects of Artemisia ordosica with different coverages in the Mu Us Sandy Land,northern China

Wind erosion is a key global environmental problem and has many adverse effects. The Mu Us Sandy Land of northern China is characterized by an arid climate, where vegetation patches and bare sand patches are usually distributed mosaically, and aeolian activities occur frequently. Vegetation plays a significant role in controlling wind erosion. Artemisia ordosica is the most dominant native plant species in the Mu Us Sandy Land. It is urgent to study the wind-proof and sand-fixing effects of Artemisia ordosica in the Mu Us Sandy Land. This study analyzed the wind-proof and sand-fixing effects of Artemisia ordosica based on the field data of wind regimes, aeolian sediment transport, and surface change of Artemisia ordosica plots with four coverages (denoted as site A, site B, site C, and site D) in the Mu Us Sandy Land during the period from 1 June 2018 to 29 June 2019. The coverages of Artemisia ordosica at site A, site B, site C, and site D were 2%, 16%, 29%, and 69%, respectively. The annual average wind speeds at 2.0 m height above the ground for site A, site B, site C, and site D were 3.47, 2.77, 2.21, and 1.97 m/s, respectively. The annual drift potentials were 193.80, 69.72, 15.05, and 6.73 VU at site A, site B, site C, and site D, respectively. The total horizontal aeolian sediment fluxes during the period from 2-3 June 2018 to 6 June 2019 at site A, site B, site C, and site D were 4633.61, 896.80, 10.54, and 6.14 kg/m, respectively. Site A had the largest surface changes, and the surface changes at site B were significantly weaker than those at site A, whereas the surface changes at site C and site D were minimal. The results indicated that Artemisia ordosica significantly reduced the wind speed, drift potential, aeolian sediment transport, and surface changes. The higher the coverage of Artemisia ordosica is, the more obvious the effects of wind-proof and sand-fixing. Wind erosion would be effectively controlled in the Mu Us Sandy Land if the coverage of Artemisia ordosica is greater than 29%. These results provide a scientific basis for evaluating the ecosystem service function of Artemisia ordosica and the vegetation protection and construction projects in the Mu Us Sandy Land.     

添加甜叶菊渣对绢蒿青贮发酵品质及苦味掩盖(去除)的影响

【目的】研究添加甜叶菊渣对绢蒿青贮发酵品质及苦味掩盖(去除)的影响，为新疆天山北坡绢蒿资源的充分利用提供理论基础。【方法】以伊犁绢蒿与甜叶菊渣为原料，按照鲜重质量比10∶0(CK处理)、9∶1(T₁处理)、8∶2(T₂处理)、7∶3(T₃处理)混合袋装青贮发酵60 d,分析营养成分、有机酸含量、发酵品质及小鼠饮水的数据(水饮用量、浸提液饮用量)。【结果】各混合比例青贮的pH值、氨态氮/总氮和丙酸含量相比对照组显著降低(P<0.05);随着甜叶菊渣添加比例的增加，各混合处理的粗脂肪、中性洗涤纤维显著低于对照组(P<0.05),可溶性碳水化合物、乳酸含量和粗灰分显著高于对照组(P<0.05);T₂处理的粗蛋白含量显著高于其他处理(P<0.05);T₂、T₃处理的乙酸和丙酸含量差异不显著(P>0.05);除对照组外各处理的酸性洗涤纤维差异不显著(P<0.05);公鼠和母鼠均对T₂处理浸提液饮用量显著高于其...     

7个野生一年生早熟禾种质萌发期耐盐性综合评价

本研究用不同浓度的NaCl和Na₂SO₄溶液处理7个野生一年生早熟禾(Poa annua L.)种子，通过测定种子萌发特性的变化，研究其萌发时的耐盐能力，以期为一年生早熟禾耐盐新品种的选育提供依据。结果表明，随着NaCl和Na₂SO₄胁迫浓度的增大，7个种质的相对发芽率、相对发芽势、相对发芽指数和相对活力指数均逐渐降低，相对盐害率逐渐增大，且同一盐浓度胁迫对相对根长的抑制普遍强于相对芽长。一年生早熟禾(湟中)种子萌发时对盐溶液的耐性最强，且Na₂SO₄对一年生早熟禾种子萌发的抑制作用大于NaCl。隶属函数法综合评价显示，7个种质萌发期耐盐性强弱依次为：一年生早熟禾(湟中)＞一年生早熟禾(甘州)＞一年生早熟禾(永昌)＞一年生早熟禾(安宁)＞一年生早熟禾(天祝)＞一年生早熟禾(凉州)＞一年生早熟禾(秦州)。综上，一年生早熟禾(湟中)和一年生早熟禾(甘州)具有培育耐盐一年生早熟禾新品种的开发应用潜力。     

藏沙蒿种质材料苗期抗旱性综合评价

为评价藏沙蒿(Artemisia wellbyi)野生种质材料苗期抗旱性，以采自我国西藏地区不同生境的13份藏沙蒿种质材料为研究对象，采用盆栽控水法模拟土壤干旱条件，设置未胁迫CK、中度和重度3个干旱胁迫处理，研究干旱胁迫对藏沙蒿材料苗期生长和生理生化特性的影响，采用主成分分析和隶属函数相结合的方法对其抗旱性进行综合评价。结果表明：干旱胁迫下，供试藏沙蒿材料的相对电导率(Relative conductivity, REC)、丙二醛(Malondialdehyde, MDA)含量、过氧化物酶(Peroxidase, POD)、超氧化物歧化酶(Superoxide dismutase, SOD)以及过氧化氢酶(Catalase, CAT)活性和脯氨酸(Proline, Pro)、可溶性糖(Soluble sugar, SS)含量均增加，可溶性蛋白(Soluble protein, SP)含量不同材料之间存在一定差异性(P<0.05);综合评价认为11号材料抗旱性最强，10号和3号次之，6号材料抗旱性最弱；建议11,10和3号藏沙蒿材料作为西藏高寒荒漠草地生态恢复和育种研究的首选材料...