点缀居室的龙血树属植物

在许多居室或办公室中,通常都摆放一、两盆巴西木或竹蕉,以美化和点缀室内的环境。这些优秀的室内观叶植物均为龙血树属植物(Dracaena)。该属植物主要分布在亚洲和非洲的热带与亚热带地区,约有40个原生种,它们中的许多种类,不仅是世界各国人民十分喜爱的室内观叶植物,而且有的还是著名的中药材,如具有止血、活血和生肌功能的“血竭”,就是从海南龙血树(D. cambodiana)的茎、枝受伤后,分泌出的红棕色树脂中提取出来的。种的叶片容易发生变异,现选育出了几个优秀的园艺品种,如大白纹竹蕉、银线竹蕉、白条纹竹蕉、月光竹蕉、金边竹蕉、密叶竹…     

发财树忌水湿

问：不久前,我从花市上买了一盆“发财树”,虽然勤浇水施肥,但叶片却逐渐变黄,很着急,想查查养花的书刊,又不知它的学名叫什么？答：发财树是近两年比较走俏的盆栽观叶植物,往往一盆三茎编成辫状出售。发财树的学名为：Pachlramao。carpa,是木棉科瓜栗属植物,中名又称瓜栗。马拉巴栗、中美木棉。该植物原产于热带美洲,为株高3－5米的小乔木,在热带及南亚热带地区呼在室外作绿化树种栽培,在北方作室内盆栽观赏。发财树虽然耐荫性较强,但却忌湿、耐旱,尤其在室内散射光下摆放,切不可洗水过多。否则根易腐烂,造成黄叶整学植株…     

少年自然科学家室内植物小组的工作

在我们学校里,栽种室内植物的小组许多年来一直在进行着工作。小组的成员主要包括6年级学生和实际上接续这一工作并对研究室内植物表现特别兴趣的7—9年级的一些学生。高年级的少年自然科学家在组织和进行小组的作业中帮我的忙。小组的主要任务如下:1)使学生认识室内植物的多样性及其对生活条件的要求;2)练会照管室内植物的实际技能,介绍一些控制其生长和发育的方法;3)培养起对植物的兴趣,并能独立地直接地研究植物有机体的生活;4)用不同方法繁殖它们来增多室内植物的数量;5)使小组工作具有公益的性质。在学校裏为小组的工作创造了必要的条件:有生物学研究室、生物角同两间自造的人工照明小室、有关生物学的必要文献和进行实际工作的用具。     

黄金葛、蔓绿绒在垂直绿化中的应用

天南星科的大叶黄金葛、白斑黄金葛、红宝石蔓绿绒、绿宝石蔓绿绒、白蝴蝶合果芋等室内观叶植物,具有栽培容易、生长迅速、叶形艳丽、四季常青、耐水湿、能攀援、可匍匐等优良性状。在厦门市园林绿化应用表明,这些植物可从室内、庭园点缀推广应用到城市垂直绿化,以丰富沿海城市垂直绿化形式。     

黄金葛,蔓绿绒在垂直绿化中的应用

天南星科的大叶黄金葛,白斑黄金葛,红宝石蔓绿绒,绿宝石蔓绿绒,白蝴蝶全果芋等室内观叶植物,具有栽培容易,生长迅速,叶形艳丽,四季常青,耐水湿,能攀援可匍匐等优良性状。在厦门市园林绿化应用表明,这些植物可从室内,庭园占缀推广应用到城市垂直绿化,以丰富沿海城市垂直绿化形式。     

微流控芯片在植物细胞研究中的应用进展

植物细胞的传统分析方法是将植物细胞在土壤或者琼脂平板上生长,然后在温室或植物生长室内观察植物的表型。这种方法耗时耗力,且结果分辨率比较低。微流控芯片具有微型化、体积小和高通量等特点,且可在微米水平精确控制植物细胞生长的微环境。因此,能够降低实验成本,缩短实验时间,并且可以达到单细胞水平的分析和鉴定。首先介绍了微流控芯片的加工材料和制备方法,总结了用于植物细胞研究的微流控芯片,重点阐述了近年来微流控芯片在植物根、花粉管、原生质体和细胞壁动力学等植物细胞研究中的应用进展,并展望了微流控芯片在植物细胞研究的应用前景。     

厦门地区室内植物的选择与配置

本文分析了室内绿化的作用,探讨了厦门地区室内植物选择和配置的方式,介绍了这一地区常见的可作为室内绿化的植物及其生态习性和用途。     

耐阴植物对空气污染在相应功能空间中的应用

甲醛是室内空气中的有害挥发性有机化合物(VOCs)之一,不仅能引起感觉刺激,而且能诱发鼻咽癌。本研究的目的是研究耐阴植物从室内空气中去除甲醛的能力以及耐阴植物景观对人体健康、生态环境等方面的作用,并对现阶段耐阴植物景观在不同功能空间的应用进行研究。采用室内棕榈树为研究对象。在48 h内将不同浓度的甲醛连续通入室内(0.66±16.4) mg/m~3来评估整株植物、生长培养基和根对去除甲醛的贡献。研究表明,长时间暴露于空气中的情况下,该植物能有效地从被污染的空气中去除65%～100%的甲醛,但是去除效果取决于入口浓度。与对照植物相比,观察到处理植物的叶绿素含量,类胡萝卜素和水含量的微量降低。因此,本研究测试的耐阴棕榈植物显示出高耐受性和从内部环境中去除甲醛的良好潜力。     

斗室绿意

隆冬时节,万物凋零,然而居室内还有很多以叶片的形状、色泽和质地为主要观赏对象的植物,它们或高大挺拔,或小巧可爱,或飘逸潇洒,将室内装点得生机盎然,它们也有一个统一的名字叫做室内观叶植物。室内观叶植物的发展起源于15世纪     

3种观赏植物对室内甲醛污染的净化及生长生理响应

在密封条件下,采取熏蒸法研究了常春藤、绿萝、驱蚊草对不同浓度梯度的甲醛气体胁迫的吸收能力及其生理响应。结果显示:(1)3种植物对室内甲醛气体均有不同程度的吸收能力,其吸收率随室内甲醛气体浓度的升高而逐渐增加,且吸收能力表现为常春藤>驱蚊草>绿萝。(2)与对照相比,随着室内甲醛气体胁迫浓度的增加,驱蚊草、绿萝、常春藤的叶绿素含量先升高再降低,而叶绿素a/b值的变化趋势各有不同。(3)不同浓度甲醛气体胁迫下,3种植物的超氧化物歧化酶(SOD)活性和过氧化物酶(POD)活性均显著升高,并以常春藤的增加量最大(分别为113.21%和120.84%),驱蚊草的增加量最小(分别为69.04%和60.76%);而3种植物的过氧化氢酶(CAT)活性与对照相比显著降低,并以驱蚊草的变化量最大(49.54%),绿萝的变化量最小(14.66%)。(4)驱蚊草、绿萝、常春藤的丙二醛(MDA)含量和脯氨酸含量随着甲醛气体浓度的增加呈升高趋势。综合分析表明,3种室内植物耐受甲醛胁迫的能力存在显著差异,常春藤属于吸收多、耐性强的植物,驱蚊草属于吸收多、耐性弱的植物,而绿萝属于吸收少、耐性强的植物。     

室内观赏植物耐摆性及更换周期调查分析——以湖南长沙地区为例

依据室内观赏植物耐摆性的评价体系,调查分析湖南长沙地区近百种室内观赏植物的耐摆性,初步确定其中55种观赏植物的更换周期。     

Evidence that ethylene signalling is not involved in selective root placement by tobacco plants in response to nutrient-rich soil patches

Ethylene is a strong controller of root development, and it has been suggested that it is involved in the increase of lateral root development in nutrient-rich soil patches (selective root placement). Here, this contention was tested by comparing selective root placement of an ethylene-insensitive transgenic tobacco (Nicotiana tabacum) genotype (Tetr) with that of wild-type (Wt) plants. Wt and Tetr plants were grown in pots with locally increased nitrate or phosphate concentrations, after which the root growth patterns were compared with those of plants grown in pots with homogeneous nutrient distribution. Tetr plants responded to nutrient patches in a similar way to Wt plants, by placing their roots preferentially at locations with higher nutrient content, and other aspects of plant morphology were also not greatly influenced by ethylene insensitivity. The response of both Wt and Tetr plants to high-nitrate patches was considerably stronger than to locally high phosphate, suggesting that the two responses are not linked in any functional or regulatory way. As the response to nutrient patches was similar in ethylene-sensing and ethylene-insensitive plants, it is concluded that selective root placement in response to nitrate or phosphate is, at least in tobacco, not mediated or modified by ethylene action.     

Do indoor plants contribute to the aeromycota in city buildings?

Many studies have focused on the sources of fungal contamination in indoor spaces. Pathogenic fungi have been detected in the potting mix of indoor plants; however, it is unclear if plants in indoor work spaces make qualitative or quantitative contributions to the aeromycota within buildings. The current work represents a field study to determine, under realistic office conditions, whether indoor plants make a contribution to the airborne aeromycota. Fifty-five offices, within two buildings in Sydney’s central business district, were studied over two seasonal periods: autumn and spring. We found that indoor plant presence made no significant difference to either indoor mould spore counts or their species composition. No seasonal differences occurred between autumn and spring samples. Indoor spore loads were significantly lower than outdoor levels, demonstrating the efficiency of the heating, ventilation and air conditioning systems in the buildings sampled. Neither the number of plants nor the species of plant used had an influence on spore loads; however, variations of those two variables offer potential for further studies. We conclude that conservative numbers of indoor plants make no substantial contribution to building occupants exposure to fungi.     

The effect of deep placement and surface application of nitrogen fertilizers at different light intensities on growth and yield of wetland rice

Summary Lowland rice (RD 3) was cultivated in containers of clay soil submerged with 5 cm water under controlled conditions in the phytotron. Deep placement of urea supergranules 5 cm in the soil significantly enhanced both plant growth and fertilizer efficiency when the plants were cultivated under high light intensity (70 Wm^–2). At the highest urea level grain yield increased 119% above the control level, while growth and fertilizer efficiency was not as high when deep placement of calcium nitrate was used.The application of urea prills and calcium nitrate (18.4g Nm^–2) in two split doses on the soil surface increased grain yield as much as 91% above the control level. At the lower nitrogen concentration (9.2 g N m^–2), the urea prills were more efficient than calcium nitrate as indicated by the grain yield. The height of those plants fertilized by surface application was affected by the concentration and not the type of fertilizer. The number of tillers, however, was significantly higher on urea fertilized plants.When the rice plants were cultivated under low light intensity 930 Wm^–2), neither the nitrogen fertilizers nor the method of application had a significant effect on growth and yield.     

竹类植物对异质生境的适应——表型可塑性

竹类植物是一类以木本为主的克隆植物,凭借表型可塑性的优势,对异质生境具有很强适应能力。然而,目前对竹类植物表型可塑性的实现方式及其异质生境适应对策未见系统总结,从而在一定程度上限制了竹类生态学的发展。从形态可塑性、选择性放置、克隆整合和克隆分工等4个方面对竹类植物的表型可塑性研究进行分析和梳理,结果表明:竹类植物在异质生境中具有明显的表型可塑反应,主要采用形态可塑性、选择性放置和克隆整合来适应异质生境,而克隆分工的普遍性仍有待验证;目前侧重于研究构件形态和生物量分配格局,而很少深入探讨形态、生理和行为等可塑性机理。今后竹类植物表型可塑性研究重点在于:1)克隆整合的格局与机理;2)克隆整合对生态系统的影响;3)克隆分工的形成及其与环境关系;4)表型可塑性的等级性及环境影响;5)不同克隆构型的表型可塑性特征及其内在机制。     

The impact of plants on the reduction of volatile organic compounds in a small space

This study aims at examining the reduction of indoor air contaminants by plants placed in an indoor space. Field measurements were performed using Aglaonema brevispathum, Pachira aquatica, and Ficus benjamiana, which were verified as air-purifying plants by NASA. Three conditions for the amount of plants and positions were used in two separate rooms whose dimensions are identical. The concentration of Volatile Organic Compounds (VOCs) was monitored three hours after the plants were placed and three days after the plants were placed. The variations of concentration of Benzene, Toluene, Etylbenzene, and Xylene (BTEX), as well as Formaldehyde, which are all known as the major elements of Volatile Organic Compounds were monitored. The amount of reduction in concentration of Toluene and Formaldehyde was monitored 3 hours and 3 days after the plants were placed in the space. The reduction in the concentration of Benzene, Toluene, Etylbenzene, Xylene, and Formaldehyde was significantly greater when plants were present. When plants were placed near a window, the reduction of concentration was greater. The more plants were used, the more a reduction of indoor air contaminants occurred. The effect of reducing the concentration of air contaminants increased when the amount of plants increased, and when the plants were placed in sunny area. The concentration of Toluene was reduced by 45.6 microg/m(3) when 10% of the model space was occupied by Aglaonema brevispathum.     

Combined effects of partial root drying and patchy fertilizer placement on nutrient acquisition and growth of oilseed rape

Partial rootzone drying (PRD) is widely investigated as an effective irrigation technique, resulting in higher water use efficiency and yield for plants growing under mild water deficit. Nutrition is another important factor affecting plant yield, but nutrient acquisition has only rarely been considered in conjunction with PRD. Here we investigate the interaction between water and fertilizer supply in a pot experiment with oilseed rape (Brassica napus L.). Eight treatments were set up for the experiment, a factorial combination of four watering regimes (100% control watering at both sides of the plants; 50% control watering at both sides of the plants; 50% fixed watering applied only to one side of the plants; 50% alternate watering applied alternately to both sides of the plant) and two fertilizer placement levels (uniform over the entire pot, and patchy supplied to one side). For the 50% watering treatments, the total amount of water supplied to the plants was the same, only the pattern of application differed between treatments. Also the total fertilizer applied was the same for all treatments. Oilseed rape roots foraged effectively for water and nutrients resulting in relatively small differences in nutrient uptake and above-ground growth among the water-deficit treatments. Placing fertilizer at one side of the plants increased nutrient uptake, but there were differences between the water treatments and interactions with water uptake. Alternate watering resulted in the highest growth, as a result of the largest nitrogen and phosphorus uptake with the smallest root investment among the three water deficit treatments. Fixed watering resulted in poorest performance when fertilizer was uniformly spread throughout the pot, because the plants were unable to acquire the nutrients on the dry side. Our results show that PRD can be well combined with patchy fertilizer supply, but that reduced nutrient uptake may be expected when nutrients are supplied in parts of the soil volume that remain too dry. Responsible Editor: Yan Li     

SCRAPP: A tool to assess the diversity of microbial samples from phylogenetic placements

Microbial ecology research is currently driven by the continuously decreasing cost of DNA sequencing and the improving accuracy of data analysis methods. One such analysis method is phylogenetic placement, which establishes the phylogenetic identity of the anonymous environmental sequences in a sample by means of a given phylogenetic reference tree. However, assessing the diversity of a sample remains challenging, as traditional methods do not scale well with the increasing data volumes and/or do not leverage the phylogenetic placement information. Here, we present scrapp , a highly parallel and scalable tool that uses a molecular species delimitation algorithm to quantify the diversity distribution over the reference phylogeny for a given phylogenetic placement of the sample. scrapp employs a novel approach to cluster phylogenetic placements, called placement space clustering, to efficiently perform dimensionality reduction, so as to scale on large data volumes. Furthermore, it uses the phylogeny‐aware molecular species delimitation method mPTP to quantify diversity. We evaluated scrapp using both, simulated and empirical data sets. We use simulated data to verify our approach. Tests on an empirical data set show that scrapp ‐derived metrics can classify samples by their diversity‐correlated features equally well or better than existing, commonly used approaches. scrapp is available at https://github.com/pbdas/scrapp .     

Early trajectories of forest understory development on reclamation sites: influence of forest floor placement and a cover crop

We tested whether direct placement of forest floor material (FFM: litter, fibric, humus layers and surface mineral horizons) and sowing of a cover crop (Melilotus officinalis) could facilitate the establishment of native forest understory species at a reclaimed coal mine in Alberta, Canada. FFM was salvaged at two depths (15 and 40 cm) from a recently harvested native aspen forest and immediately placed at the same depths on the reclamation site. Total richness (approximately 61 species in 96 subplots) was similar in each of 3 years post‐placement; total richness for all 3 years combined was 87 including 34 typical boreal forest understory species plus 30 other natives. The deeper treatment reduced cover of all species, native and non‐native species in year 1. In year 3, the deeper treatment still had lower cover of non‐native species but had higher cover of forest understory species in years 2 and 3. The deeper treatment also resulted in lower species richness per plot, but only in year 1. In year 2 (when the biennial clover was at its tall stage), the cover crop treatment was associated with lower cover of non‐native species but did not affect the cover of native forest understory species. Direct placement of FFM can help facilitate establishment of a diverse native boreal forest understory in a reclaimed landscape. Although richness and cover may be initially higher with shallower salvage and placement, deeper salvage may ultimately be better for encouraging establishment of native forest understory species.