臭菜扦插技术研究

以野生臭菜的枝条为扦插材料,研究了其的扦插技术。经作插条不同时间的流水浸泡、不同扦插季节及基质、不同插条状况(插条的不同长度、直径、年龄)、不同药剂浸泡插条等的扦插技术处理对臭菜扦插生根率影响的试验研究后,而获得了臭菜扦插的最佳技术方案。该方案为:在春季(2月)选取直径1.0~2.0 cm的2~3年生枝条,去叶后剪成长15~20 cm的插条,经过12 h流水浸泡处理后,再用100 mg/L的ABT1号生根粉浸泡基部12 h,扦插在珍珠岩中,保持其基质的含水率为60%。可以使臭菜插条的生根率达到79.2%。     

羽毛针禾（Stipagrostis pennata）克隆构型及不同环境中的分株种群特征

以古尔班通古特沙漠不同环境（沙丘不同坡位、不同伴生植物、不同流动性沙丘）中的羽毛针禾（Stipagrostis pennata）种群为研究对象,通过测定羽毛针禾分株平均高度、节间长、分蘖株数、根茎直径、地下根状茎数、平均地下根状茎长等指标,分析羽毛针禾的克隆构型及不同环境中的分株种群特征。结果表明：羽毛针禾分株强度大,分枝多,分株间的间隔物（节间长）高度缩短,表现出典型的“密集型”克隆生长构型。同时,比较半固定沙丘不同坡位羽毛针禾的分株种群特征,坡顶上的羽毛针禾在分蘖株数和平均根状茎长均显著高于坡底;分析羽毛针禾与不同伴生植物的分株种群特征表明,羽毛针禾与鹤虱的伴生群落中,其分蘖枝数显著高于羽毛针禾与白茎绢蒿的伴生群落,且有较高的分枝密度和较短的平均根状茎长;与半固定沙丘相比,生长于固定沙丘的羽毛针禾分株种群具有显著的分蘖株数、根状茎数,以及较长的根茎直径、较大的地上部分生物量和地下根状茎生物量。最后,结合克隆植物对资源的利用对策及表型的可塑性,对不同环境中的羽毛针禾分株种群特征进行了讨论。     

新疆三芒草DREB基因片段的克隆

[目的]克隆新疆三芒草DREB基因片段。[方法]利用PCR技术和RACE技术,从新疆沙漠边缘抗旱植物三芒草中克隆抗旱相关基因DREB片段。[结果]研究克隆到了4个DREB基因片段。[结论]该研究为进一步获得DREB基因全序列和研究植物抗旱分子机理、培养抗旱作物品种奠定了基础。     

SSR标记对大颖针禾种群遗传结构的研究

以大颖针禾7个不同地理种群100个样本为研究对象,利用SSR技术从群体水平进行遗传结构的研究。结果表明:大颖针禾遗传多样性丰富,Nei’s基因多样性指数H=0.2244,Shannon多样性指数I=0.3355,这2个指标都在YT种群最高,MSS种群最低;大颖针禾种群的遗传分化系数Fst=0.5475,即在总的遗传变异中有54.75%存在于种群间,种群间遗传距离GD变幅为0.0871~0.2441,地理距离和遗传距离之间无相关性;通过聚类分析,以遗传距离0.14为标准,大颖针禾种群可划分为4个类群。     

Effects of temperature and water limitation on the germination of Stipagrostis ciliata seeds collected from Sidi Bouzid Governorate in Central Tunisia

Most ecological studies in North Africa reveal a process of continuous degradation of rangeland ecosystems as a result of overgrazing. This degradation appears across the decreasing of perennial grass diversity. Indeed, the majority of steppe ecosystems are characterized by a low density of perennial grass species at present. This study evaluated the effects of temperature and water limitation on the seed germination of Stipagrostis ciliata(Desf.) de Winter, a perennial grass species. The seeds were collected from the Bou Hedma Park, Sidi Bouzid Governorate, Central Tunisia. The thermal time and hydrothermal time models were used to describe the seed germination of S. ciliata under different water potentials and temperatures. The germination response of S. ciliata seeds in darkness was evaluated over a range of temperatures(15°C, 20°C, 25°C, 30°C and 35°C) and across a wide range of osmotic potentials(0.0, –0.2, –0.6, –1.2, –1.6 and –2.0 MPa) of the polyethylene glycol(PEG6000) solutions at each temperature level. Among the tested temperatures, 25°C was found to be the optimal temperature to the germination of S. ciliata seeds. The final germination percentage(75.2%) was obtained with distilled water. The progressive decrease of osmotic potential of the PEG6000 solutions inhibited the seed germination. However, the number of days to first germination was increased with a reduction of osmotic potential. A significant positive relationship was identified between final germination percentage of S. ciliata seeds and osmotic potential of the PEG6000 solutions, with R~2 ranging from 0.5678 to 0.8761. Furthermore, a high degree of congruency between predicted and observed germination time course curves was observed. In general, S. ciliata exhibits a significant adaptation capacity for water limitation and high temperature in arid ecosystems.     

云南热区的5种木本森林蔬菜及其培育技术

先对云南热区的臭菜、刺五加、南山藤、越南甜菜和长蕊甜菜5种木本森林蔬菜的特性作了介绍。继后从苗木培育(包括苗圃地及其相关设施的设置, 种子及插条育苗, 苗期管理) 和苗木栽培(包括种植地选择,种植技术, 修剪) 两方面简述了这5种木本森林蔬菜的人工规模化培育技术。     

新疆针禾属(Stipagrostis Nees)植物叶片解剖结构的比较

利用光学显微镜,对新疆荒漠中针禾属植物大颖针禾(Stipagrostis grandiglumis)和羽毛针禾(Stipagrostis pennata)叶片进行微观形态结构特征的观察与比较.结果表明:大颖针禾和羽毛针禾的叶都具有典型的适应干旱及沙漠环境的形态结构特征;2种针禾叶片表面均具有角质层,但厚度不同;两者上表...     

羽毛针禾组织培养方法研究

[目的]筛选适合于羽毛针禾种子发芽的培养基及愈伤组织诱导培养基。[方法]以羽毛针禾种子为基础材料,以MS培养基为基本培养基,研究不同激素浓度配比条件下种子发芽率及愈伤组织的诱导效果。[结果]6-BA对羽毛针禾种子的萌发作用不太明显,但加入6-BA后有利于种子个体的生长发育;GA3对羽毛针禾种子的萌发起着关键性的作用。种子发芽最适培养基为1/2 MS+GA32.0 mg/L,可诱导出结构致密、绿色颗粒状胚性愈伤组织。较高浓度的2,4-D可促进愈伤组织较快发生,但浓度过高对胚性愈伤组织的诱导有抑制作用且容易导致愈伤组织的褐化现象,只有当2,4-D浓度为2.0 mg/L时,胚性愈伤组织的诱导率达最大值,得到最好的培养效果。种子愈伤组织的诱导以MS+2,4-D 2.0 mg/L+6-BA 0.5 mg/L为宜。[结论]为完善羽毛针禾的高频再生体系和基因转化奠定了基础。     

Effects of water stress on growth phenology photosynthesis and leaf water potential in Stipagrostis ciliata (Desf.) De Winter in North Africa

Stipagrostis ciliata (Desf.) De Winter is a pastoral C₄ grass grown in arid regions. This research work focused on assessing the growth of S. ciliata accessions derived from two different climate regions (a wet arid region in the Bou Hedma National Park in the central and southern part of Tunisia (coded as WA), and a dry arid region from the Matmata Mountain in the south of Tunisia (coded as DA)) under water stress conditions. Specifically, the study aimed to investigate the phenological and physiological responses of potted S. ciliata seedlings under different water treatments: T₁ (200 mm/a), T₂ (150 mm/a), T₃ (100 mm/a) and T₄ (50 mm/a). Growth phenology, net photosynthesis (P_n), stomatal conductance (g_s), midday leaf water potential (Ψ_md), predawn leaf water potential (Ψ_pd), soil water content (SWC) and soil water potential (Ψ_s) were observed during the water stress cycle (from December 2016 to November 2017). The obtained results showed that the highest growth potential of the two accessions (WA and DA) was recorded under treatment T₁. The two accessions responded differently and significantly to water stress. Photosynthetic parameters, such as P_n and g_s, decreased sharply under treatments T₂, T₃ and T₄ compared to treatment T₁. The higher water stress increased the R/S ratio (the ratio of root dry biomass to shoot dry biomass), with values of 1.29 and 2.74 under treatment T₄ for accessions WA and DA, respectively. Principal component analysis (PCA) was applied, and the separation of S. ciliata accessions on the first two axes of PCA (PC1 and PC2) suggested that accession DA was detected in the negative extremity of PC1 and PC2 under treatments T₁ and T₂. This accession was characterized by a high number of spikes. For treatments T₃ and T₄, both accessions were detected in the negative extremity of PC1 and PC2. They were characterized by a high root dry biomass. Therefore, S. ciliata accessions responded to water stress by displaying significant changes in their behaviours. Accession WA from the Bou Hedma National Park (wet arid region) showed higher drought tolerance than accession DA from the Matmata Mountain (dry arid region). S. ciliata exhibits a significant adaptation capacity for water limitation and may be an important species for ecosystem restoration.     

羽毛针禾种群遗传多样性分析

[目的]从分子水平对羽毛针禾居群内、居群间的遗传分化进行研究,揭示其遗传多样性水平。[方法]使用11条RAPD引物对生长于古尔班通古特沙漠的优良固沙植物羽毛针禾进行居群遗传变异分析。[结果]7个居群76个样品共检测到125个位点,总多态位点百分比为96.8%,居群内平均多态位点百分比为45.3%;羽毛针禾种群Shannon表型多样性指数（I）为0.5151,Nei’s基因多样度指数（h）为0.3471;居群间的基因分化系数为0.5284,即有52.84%的遗传多样性存在于居群间。[结论]羽毛针禾居群有较为丰富的遗传变异,且各居群间已有了明显分化。