白芥离体快繁体系的建立

以白芥幼苗为外植体,MS和1/2MS为基本培养基分别加入不同浓度的6-BA、NAA和KT进行白芥离体再生技术体系研究.结果表明:以白芥幼苗为外植体进行培养,其不定芽增殖效果较好.6种不定芽增殖培养基增殖效果存在明显差异,其中最适宜的芽增殖培养基是MS+1mg/L 6-BA+1mg/L KT,侧芽及不定芽生长迅速、且旺盛,2周后不定芽平均增殖到10个;大量元素含量对幼苗的壮苗具有显著效应,其中3MS培养基的壮苗效果最好,培养21d的苗较对照明显变粗壮;组培苗接种在1/2 MS+0.133mg/L NAA的培养基上诱导生根的效果最佳,茎段培养约15d时发现白色根,主根较多、细长,有侧根,每单株可达7条根.     

对在海南建设生态桑树种植园的探讨

文章通过对桑树的形态特征、生态习性、种植的阐述,以其果实桑葚的经济价值及开发为重点进行分析,提出了在海南建设以种植果桑为主的生态桑树种植园的想法,并对其必要性、可行性进行了论述。     

Assessment of Environmental Effects of the Coal used in the Seyitömer Thermal Power Plant (Turkey) on White Willow

Abstract

Thermal power plants increase local pollution through SO_x, NO_x, volatile organic compounds (VOCs), and oils containing primarily particulates (including heavy metals) and increase global pollution through CO₂, the greenhouse gas that causes global warming. These strong pollutants have harmful effects on living organisms and the entire ecosystem. In this study, we analysized the heavy metals iron (Fe), cadmium (Cd), chromium (Cr), copper (Cu), zinc (Zn), lead (Pb), nickel (Ni), and sulfur (S) induced by sulfur dioxide found in the both washed and unwashed leaves of Salix alba L. tree, grown in six distinct localities in the vicinity of the Seyitömer thermal power plant, to assess the environmental impact. All parameters were examined in the surface soils (0–30 cm), and the most intense concentration of the pollutants in both soils and leaves was observed to be in the direction of the prevailing wind.     

Clinical and ultrasonographic evaluation of three suture techniques for closure of the equine linea alba

Surgical technique plays an important role in preventing ventral midline incisional complications. The aim of this study was to compare the clinical and ultrasonographic outcome of three suture techniques for closure of the linea alba. In this prospective case series (n = 43), horses operated for acute abdominal intestinal disease through a midline incision were randomised in three groups: closure with a conventional continuous technique (Group 1), a small stitches continuous technique (Group 2) and the UX-technique (shoe-lace configuration, Group 3). Age, sex, body weight, type and duration of surgery were recorded and the suture to wound length ratio was calculated. Clinical evaluation of the wound (wound discharge) was performed daily during hospitalisation. At 7 weeks post-operatively the linea alba was evaluated clinically and ultrasonographically. The linea alba width was measured halfway along the length of the incision. One horse in Group 1 had acute incisional dehiscence, but there were no further significant differences between the groups in the short term. Seven weeks post-operatively two horses had complete herniation in Group 1 and one horse had partial herniation in Group 2. In the UX group no herniation occurred. The incidence of herniation was not significantly different between the groups. On ultrasound at 7 weeks the linea alba width was significantly smaller in Group 2 (P = 0.00029) and Group 3 (P = 0.0018) compared with Group 1, even with exclusion of the acute incisional dehiscence and two herniated horses. Limitations were the small group size and relatively low incidence of incisional complications for statistical analysis. It was concluded that the use of small stitches and the UX-technique resulted in a smaller linea alba width compared with the conventional continuous suture technique and might therefore be preferred for closure of the linea alba in equine colic surgery.     

银白杨硬枝扦插初步研究

在西藏采用ABT生根粉处理银白杨插穗进行扦插育苗效果显著，其中，以6号ABT100mg/kg浸泡插穗基部6h的效果最好，其生根率可达91%。     

广昌白莲研究进展

综述了广昌白莲的研究现状,并展望了其发展方向。     

白兰开花过程中花被片结构的变化与释香机理

应用光学显微镜和扫描电镜对白兰(Michelia laba DC.)花开放过程中花被片结构的变化进行了观察,并与成熟叶片的结构特征进行了比较,对白兰成熟花被片与成熟叶片的一些数量特征进行了测量,探讨了白兰花香气形成、挥发部位及挥发途径的结构基础。结果表明:(1)根据在花被片开展的不同时期的颗粒状细胞内含物的数量、形态及存在部位,推测白兰花被片颗粒状细胞内含物可能主要是香气释放前体物质。(2)白兰花被片与成熟叶片的解剖结构存在差异,表明花被片与叶片香气释放机理不一致。白兰花被片挥发性香气的前体物在基本薄壁组织细胞中产生,通过扩散作用输送到表皮细胞,最后通过表皮细胞的垂周壁、表皮细胞的细胞间隙、气孔释放出来。     

观赏性灌木堰伏梾木的生物学特性与快繁技术研究

本文对筛选出的观赏型优良灌木——堰伏木来木的分布、生物学和林学特性、快繁技术等进行了研究,从而为生态建设与建立经济型社会主义新农村提供利用资源。     

Variation Between Barley Cultivars in Early Response to Weed Competition

An experiment was conducted with three spring barley ( Hordeum vulgare ssp. vulgare L.) cultivars of contrasting competitiveness to identify variations in their early competitive response to weed competition and to study canopy architecture and growth development at the early stages of cultivar growth. The aim was also to investigate whether differences in shoot morphology, growth development and competitive response could explain the differences in competitive ability against weeds. The barley cultivars were grown outdoors in boxes either in monoculture or in a mixture with white mustard ( Sinapis alba L.) as a model weed. The experiment was run until the barley cultivars were in the stem elongation stage. The varieties with strong to medium competitive ability against weeds shortened the time of emergence in the presence of S. alba in contrast to the least competitive cultivar. The results also indicated that spring barley cultivars with strong competitive ability against weeds have an early stem extension as a response to weed competition and a low competitive response. Morphological traits, namely large length of the two first internodes, long main shoot in the tillering stage and a small leaf angle, may be important traits in competition for light.     

Host range of the parasitic weed Osyris alba L. in Jordan

A field survey revealed the presence of Osyris alba L., the root hemi-parasitic weed, with 23 plant species of 14 families found in the central/west parts of the Hashemite Kingdom of Jordan. The host list includes shrubs and fruit and forest trees of high economic value. New hosts were added to the existing list. The most severely attacked fruit trees are Amygdalus communis L., Olea europaea L., and Vitis vinifera L., while the most severely attacked forest trees are Cupressus sempervirens L . , Acacia cyanophylla Lindl. and Rhamnus palaestina Boiss. The distribution and intensity of parasite infection of different hosts were evaluated. This work is the first record of O. alba and its hosts in the Kingdom of Jordan.