不同基质对越橘生长发育和叶片光合特性的影响

以二年生"都克"越橘苗木为试材,采用CIRS-2便携式光合仪测定光合指标与LA2400扫描仪扫描根系的方法,研究了不同栽培基质对越橘生长发育和光合作用的影响,以期筛选出越橘基质栽培中最佳配比。结果表明:在泥炭藓∶草炭∶珍珠岩=2∶1∶1、椰糠∶草炭∶珍珠岩=2∶1∶1、苔藓∶草炭∶珍珠岩=2∶1∶1这3种基质下植株生长发育较好,光合作用较强,其中泥炭藓∶草炭∶珍珠岩=2∶1∶1基质效果最好;秸秆∶草炭∶珍珠岩=2∶1∶1、松针∶草炭∶珍珠岩=2∶1∶1效果较差,植株生长发育不良。     

Water relations of nursery potting-media

The available water-holding capacities (AWHC) of different potting-materials varied widely; coarse sand has a very low AWHC, and peat moss, sawdust, poppy straw and brown coal each have a high AWHC. The AWHC determines the length of time taken for plants to wilt, except in the case of peat moss and pinebark. Much of the available water in peat moss is rapidly lost through evaporation and easy exploitation by the plant. Pinebark, because it resists water loss through evaporation, and because its available water is not readily accessible to the plant, is able to maintain plants unwilted for a longer time than peat moss despite its lower AWHC. The AWHC and wilting-time of mixtures of 2 potting materials can be predicted from their individual properties.     

Growth of Viburnum tinus in peat-based and peat-substitute growing media

To assess the growth of ornamental shrubs in peat alternative substrates, one ornamental species, Viburnum tinus L., was cultivated in a number of different substrates in two climates: a French oceanic (Oce) and a Spanish Mediterranean (Med). In Oce, three mixtures (1/1, v/v) of Finnish peat/yard compost, yard compost/raw coir and Finnish peat/raw coir were used while the expanded perlite/composted manure (1/1), forest compost/composted bark (1/1) and forest compost/cattle manure compost (2/3) were tested in Med. A mixture (1/1) of Finnish peat/pine bark compost was used in both climates as a control. Plants were cultivated at a density of six plants/m² in 4 l containers with drip irrigation. Plant height, dry mass, and leaf area were measured at intervals during cultivation. In Oce, substrates with yard compost or raw coir produced plants of similar size to those in the control substrate. In Med, forest compost/cattle manure compost mixture produced plants with the same height as those in the control mixture and the two other mixtures produced shorter plants. In both climates, substrates ranked the same whether height, dry mass or leaf area were considered. Using those parameters, significant effects of different substrates were revealed. Those effects are related to the substrate characteristics, mainly physical ones. As peat is used in a large range of situations, the experiment showed that substrate performance varies with its use, so alternative substrates can show better performance than those using peat.     

Vegetation development over four years on two green roofs in the UK

Carefully designed green roofs have the potential to be used as mitigation for habitats lost at ground level. The development of plant assemblages on two green roofs designed to emulate diverse brownfield habitats (brown roofs), by using recycled demolition aggregate as part of a low-fertility growth substrate, were studied over the first four years of their development. The cover-abundance of flowering plants and habitat structural components (e.g. bare ground, moss) were measured on the Domin-Krajina scale within all identified microhabitats. Drought disturbance was one of the main controlling factors on assemblage development. Annual plants were abundant and successful in the first growth season, and thereafter only re-appeared in any numbers following drought disturbances in subsequent years. Moss and Sedum acre L. increased through the study period until these plants dominated coverage. The cover-abundance of perennial wildflower species was strongly influenced by drought disturbance. The influence of drought disturbance varied between different brown roof microhabitats, with plant assemblages in coarser and less fertile microhabitats more resistant to these disturbances. Observed responses to drought were consistent with the following two hypotheses: (i) Areas of coarse substrate can act as disturbance refugia for plants during drought by helping preserve pockets of water under large clasts and within absorbent materials such as brick. (ii) The plant assemblages living in areas of more fertile substrates, which grow more luxuriantly when water availability is high, are more vulnerable to drought disturbance. Green roofs should be designed to include a range of substrate types to create several microhabitats that will collectively support more species than any single microhabitat.     

Morpho-physiological plant quality when biochar and vermicompost are used as growing media replacement in urban horticulture

Peat moss is the most used soilless substrate in the production of container plants in floriculture. Nevertheless, the drainage of peat bogs due to the peat extraction has increased the necessity of seeking products that could replace the peat that is used in plant production. Therefore, a comparative study was conducted to evaluate the effect of a biochar (B) - vermicompost (V) mixture, as a partial substitute for peat-based substrates, on the morpho-physiological characteristics of ornamental plants. Different blends containing B and V were compared to a baseline peat-based substrate (S) as control in the cultivation of two ornamental bedding plant species that are widely used in urban areas: geranium (Pelargonium peltatum) and petunia (Petunia hybrida). Plant growth and physiological parameters were assessed. Results showed that it is possible to grow container plants of these two species with commercial quality, using a peat-based substrate mixed with biochar and/or vermicompost (up to 30% V and 12% B). Plants in these substrates showed a similar or enhanced physiological response to those grown in the control using commercial peat-based substrate.     

Micropropagation of Dendrobium draconis Rchb. f. from thin cross-section culture

An efficient procedure is outlined for rapid and mass in vitro propagation of an orchid, Dendrobium draconis Rchb. f. through in vitro culture of thin cross-sections (TCSs) derived from young stems. The TCS explants were excised along the stem from the base to shoot tip of 6-month-old plantlets and cultured on Murashige and Skoog (MS) medium supplemented with 20 g/l sucrose and different concentrations of N⁶-benzyladenine (BA), kinetin (Kn) and 1-naphthaleneacetic acid (NAA), either individually or in combination. Protocorm-like bodies (PLBs) were directly induced from the TCS explants and completely developed into shoots within 6–7 weeks. The optimal growth regulators combination for maximal PLB development was 2 mg/l BA and 1.0 mg/l NAA, giving rise to 68% of responding explants with an average 11 PLBs per explant. Shoot development was best achieved on MS medium containing sucrose and coconut water. Plantlets, 6–8 cm height were transplanted into coconut husk peat with 92% survival rate in a nursery.     

东方百合品种‘西伯利亚’切花生产中替代泥炭的基质研究

以东方百合品种‘西伯利亚’（‘Siberia’）为试材,研究了在混配基质中用麦秆、玉米秆、椰糠、菇渣、豆荚等5种有机废弃物替代泥炭作为栽培基质的可行性。结果表明,5份泥炭︰2份珍珠岩︰1份蛭石︰2份麦秆、4份泥炭︰2份珍珠岩︰1份沙子︰3份玉米秆、2份珍珠岩︰2份蛭石︰3份椰糠︰3份沙子（均为体积比）等3种混配基质的各项理化指标均在无土栽培基质的理想范围内,用其栽培的百合,生长发育综合表现优于目前生产上常用的含70%泥炭的基质,其中又以4份泥炭︰2份珍珠岩︰1份沙子︰3份玉米秆的基质最优。     

不同育苗基质对浅液流水培莴苣生长的影响

摘要：为筛选出适宜莴苣浅液流水培的育苗基质，研究对比了6种商品化育苗基质（花泥30、泥炭块38、泥炭块30、椰糠块30、岩棉块36、岩棉块25）对奶油莴苣“富兰德里”生长的影响。结果显示：在同期播种、同期定植、同期采收条件下，使用泥炭块38、泥炭块30、椰糠块30等商品化基质育苗更有利于莴苣苗期和定植后的生长，其次为岩棉块36、岩棉块25处理，使用花泥30育苗效果最差；在同期播种、4叶1心期定植、同株质量标准采收情况下，使用泥炭块38、泥炭块30等商品化基质育苗的莴苣生长周期最短，其次为椰糠块30、岩棉块36、岩棉块25处理，使用花泥30育苗的莴苣生长周期最长。综合来看，对于浅液流水培莴苣，使用泥炭块38、泥炭块30、椰糠块30商品化基质育苗效果较好，莴苣苗期和定植后长势好，生长周期短，考虑到育苗成本，推荐使用泥炭块30或椰糠块30进行育苗。     

Water-use efficiency and evapotranspiration of mango orchard grown in northeastern region of Brazil

Knowledge of evapotranspiration (ET) and water-use efficiency (WUE) is essential in crops management mainly in arid and semiarid regions where water resources are scarce for irrigation. Field experiments were conducted at a commercial farm to obtain the WUE and ET of mango orchard growth in a semiarid environment of northeastern region of Brazil. Measurements were performed within a randomly selected experimental plot with the spacing of 10 m × 5 m between rows and plants. Soil water balance method was used to obtain the mango orchard evapotranspiration while the Penman–Monteith method (FAO/56) was used for determination reference evapotranspiration (ET_o). Soil water content was determined by six tensiometer sets installed at 0.20 m layer intervals from the soil surface down to 1.20 m soil depth. The experimental plot was irrigated with a sprinkler irrigation system based on four irrigation levels (T1 = 70%, T2 = 80%, T3 = 90% and T4 = 100% of ET_o. Results showed that ET and WUE are strongly influenced by soil water availability. Mango yield varied from a minimum value of 28.06 ton/ha in treatment T4 to a maximum value of 31.06 ton/ha in treatment T3. Such difference was found to be statistically significant (P < 0.05) by Tukey's test. Results also indicated that WUE values based on irrigation and evapotranspiration were maximum and minimum for low (treatment T1) and high (treatment T4) water levels, respectively.     

Suitability of wood fiber substrate for production of vegetable transplants: I. Physical properties of wood fiber substrates

Several experiments were conducted with the objective to find suitable alternatives for peat substrates. Physical properties of wood fiber substrates in comparison to other organic substrates were examined. Volume weight, total pore space, pore size distribution, available water, container and air capacity, saturated hydraulic conductivity and volume loss of these substrates were determined. Wood fiber substrates showed a similar volume weight and total pore space as peat substrates, but lower water retention. Particularly the drainage performance of wood substrates results in a quick drainage of surplus water. An increase of volume weight caused a decrease of total pore space, air content and saturated hydraulic conductivity and an increase in water retention. Evaluation of these parameters under container conditions is critical since they are directly related to irrigation and therefore to plant growth. A compression of wood fiber substrates in the pots is recommended to minimize substrate loss. An increase of compression levels reduced the volume loss to almost 0 vol.%. The effect of wood fiber substrates and their volume weight on plant growth will be reported in a second paper.     

Performance of herbaceous Evolvulus pilosus on urban green roof in relation to substrate and irrigation

Rooftop gardening (or green roof establishment) is an urban greening afforestation method that has many environmental, economic, and urban landscaping benefits. For rooftop vegetation, stressful environments that include heat, strong winds, sunshine, and drought prevent many plants from growing well, especially in shallow soil. To establish low cost urban rooftop gardens with a low weight substrate in the summer, we evaluated the green coverage and growth of a suitable groundcover ornamental plant, blue daze (Evolvulus pilosus). Blue daze was used as rooftop vegetation in a shallow substrate (10 cm thick) on the flat rooftop of a four-story building in the middle of Kobe city, Japan, which has a temperate and humid climate. On average, the diurnal maximum temperatures and the total amounts of precipitation during each planting experiment between July and September were 30.8 °C and 247 mm in 2008 and 33.2 °C and 458 mm in 2009, respectively. Three different types of planting substrates (AS, amended soil, TM, turf mat as a dried-up blocks of sod, and FBA, furnace bottom ash) were tested to determine how they influenced plant cover, flowering, and growth. We evaluated the physical and chemical properties of the substrates that were used to establish the rooftop greeneries. In addition, the economy, ornamental and ecological values, reuse of material, and low rooftop weight burdens of the substrates were evaluated. The greatest blue daze ground cover occurred on the TM substrate (relative to the AS and FBA substrates) approximately three months after transplanting. The blue daze actively bloomed on all substrates throughout midsummer. However, alternate day irrigation largely reduced their shoot growth and flowering relative to daily irrigation. The AS and TM substrates had suitable physicochemical properties for use as planting substrates and had ideal solid, liquid, and vapor phase distributions and high water and nutrient holding capacities. FBA was a poor substrate with very low water and nutrient retention capacities, which resulted in depressed plant growth, especially under low watering conditions. To recycle FBA efficiently as a shallow low-cost planting substrate for rooftop gardening, the addition of coated fertilizers and organic matter to FBA should be considered to improve its water and nutrient holding capacities.     

Osmotic adjustment,proline accumulation and cell membrane stability in leaves of Cocos nucifera submitted to drought stress

The role of drought-induced proline accumulation in coconut leaves is still unclear. With the objective of evaluating the impact of water shortage on leaf osmotic potential, proline accumulation and cell membrane stability in young plants of two Brazilian Green Dwarf coconut ecotypes from contrasting areas (Brazilian Green Dwarf from Una, Bahia, UGD, and from Jiqui, Rio Grande do Norte, JGD), a pot experiment was conducted under greenhouse conditions. Three drought cycles consisting of suspension of irrigation until the net photosynthetic rate (A) approached zero and rewatering until recovery of A to 85% of the irrigated control plants. Pre-dawn leaf water potential (Ψ_PD) reached −1.2 MPa at the point of maximum stress (PMS). Dry matter production and leaf area were severely reduced by drought treatment in the two ecotypes. Corrected values of osmotic potential were significantly reduced in stressed plants of the two ecotypes. Green dwarf coconut palm showed low osmotic adjustment (from 0.05 to 0.24 MPa) and significant accumulation of proline (from 1.5 to 2.1 times in relation to control) in leaflets in response to water deficit. Considering the growth reduction observed in both ecotypes, proline was not associated to osmoregulation. On the other hand, the absence of membrane damage, as indicated by electrolyte leakage method, suggests that the protective role of proline in this specie can be more important. The two ecotypes of Green dwarf coconut palm behaved similarly in the present experiment for most traits evaluated. Slight differences among the ecotypes were observed with respect to the response to treatments, such as higher proline accumulation in JGD.     

In vitro and in vivo assessment of the potential of compost and its humic acid fraction to protect ornamental plants from soil-borne pathogenic fungi

Five humic acid fractions (HAs) were isolated from various organic substrates used for plant growth in containers, including both conventional ones, i.e. peat (P) and coconut fiber (CF), and newly introduced ones, i.e. compost (Co) and mixtures at 20% and 60% (v/v) of Co with P (Co20 + P and Co60 + P) and Co with CF (Co20 + CF and Co60 + CF). The effects of these HAs at 50 and 300 mg L⁻¹ were evaluated on the mycelial growth of two soil-borne phytopathogens, Pythium ultimum (PYT) and Fusarium oxysporum f. sp. callistephi (FOC), in a series of in vitro experiments. Furthermore, in experiments performed in a climatic chamber, the bulk substrates were tested on the growth and health of two ornamental plant species: impatiens (Impatiens walleriana Hook) and China aster (Callistephus chinensis L. Nees), repeatedly infected respectively with PYT and FOC. In general, any HA at either dose reduced significantly the radial growth of PYT mycelium after 42 h, whereas Co-HA and P-HA at the higher concentration showed a high inhibition on PYT during the whole experiment. A significant inhibition of FOC growth was exerted by all HAs, especially at the higher dose, during the 192-h experimental time. No significant correlation exists between the extent of the inhibitory action on the two fungi and the chemical and functional properties of HA. The only exception is the existence of a negative correlation between the inhibition of PYT and the HA oxygen content. The various substrates used in trials conducted in vivo caused different plant growth response. The treatments with Co alone or its mixtures at 60% with P or CF were lethal for both plants, even before the first fungal inoculation. The substrates Co20 + P and Co20 + CF were very effective in controlling the fungal attack and increasing the growth of impatiens and China aster.     

保定室外绿墙火焰南天竹的生理变化研究

为了研究越夏期间,保定市室外绿墙上火焰南天竹的生长状态,对自然区域生长基质为草炭、水苔的火焰南天竹及防寒区域生长基质为草炭、水苔的火焰南天竹进行生理指标测定,并用隶属函数对其进行综合评价.结果 表明:绿墙上日平均光照强度变化范围为0.38～20860.76 Lx,基质日均温度变化范围为6.22～29.55℃,日均湿度变化范围为12.74％～26.40％时,火焰南天竹叶绿素含量及保护酶活性变化规律为升一降;MDA变化规律为降-升-降;营养物质变化规律为升-降-升.自然区域草炭、自然区域水苔、防寒区域草炭、防寒区域水苔基质处理下火焰南天竹叶绿素含量均值分别比CK增加了26.21％、13.71％、66.13％、50.81％;SOD均值分别比CK增加了22.27％、10.44％、37.79％、27.96％;POD均值分别比CK增加了33.22％、15.16％、66.45％、48.19％;可溶性糖含量均值分别比CK增加了53.45％、33.47％、14.53％、89.44％;可溶性蛋白含量均值分别比CK增加了14.22％、6.77％、28.33％、21.69％;MDA含量均值分别比CK降低了31.52％、14.63％、50.84％、35.48％.防寒区域火焰南天竹叶绿素、SOD、POD、可溶性糖、可溶性蛋白含量均值分别比自然区域增加了32.10％、14.20％、26.68％、51.51％、13.14％,MDA含量均值下降了21.62％.各处理下火焰南天竹抗性由强到弱依次为防寒区域草炭基质、防寒区域水苔基质、自然区域草炭基质、自然区域水苔基质.综上所述,防寒区域草炭基质处理最有利于火焰南天竹生长.     

Effect of combined water and salinity stress factors on evapotranspiration of Sedum kamtschaticum Fischer in relation to green roof irrigation

In dryland areas, secondarily treated municipal wastewater could be used in extensive green roof systems. In this study, the effects of water and salt stress on a crassulacean acid metabolism (CAM) plant, Sedum kamtschaticum Fischer, was evaluated under intermittent saline irrigation. The salinity of irrigation water varied from 6.0 to 18.0 dS m^?1. A reduction in soil water content and an increase in soil water electrical conductivity (EC) were observed during the irrigation interval (5–17 d) as a result of evapotranspiration (ET). The effect of soil water potential (SWP) on reduction of the ET ratio (ET_r) was successfully described with an equation that could be applicable to a wide range of soil salinities and water contents, to estimate ET. In this study, the stress factor was defined as the integration of solute potential, and matric potential less soil water content for optimum growth (less than ?0.1 MPa) with elapsed time. The stress factor rapidly reduced total ET in CAM plants but effectively increased water-use efficiency (WUE). Thus, by using CAM plants for green roofs under intermittent saline irrigation, the need for irrigation water is reduced without a considerable loss of plant biomass.     

Root development of Thuja plicata in peat-substitute rooting media

In this study we investigated the potential usefulness of different substrates produced from gorse (Ulex europaeus L.) for propagating cuttings of Thuja plicata ‘Atrovirens’. The gorse was composted by different methods, to produce four types of compost. These composts were then used as such (100% compost) or in mixes with coarse sand and pine bark compost (25% compost, 25% coarse sand and 50% pine bark compost, v/v/v) to prepare eight different substrates. The substrates were compared in cutting propagation trials carried out in a greenhouse, with a standard rooting medium consisting of 25% Sphagnum peat moss, 25% coarse sand and 50% pine bark compost (v/v/v). Cuttings were taken from a garden hedge in March 2003, and comprised shoots of the previous year's growth. The bases of the cuttings were treated with a 0.4% solution of IBA rooting hormone, then inserted into cells filled with the corresponding substrate and placed on a propagation bench. Rooting percentage and visual rooting score were determined in July. The quality of roots was evaluated, as total root length and number of root tips, in July, September and November 2003, by use of a Delta-T Scan system. The rooting success of the cuttings ranged from 75% to 90%, except when the substrate comprised the pure composted gorse, obtained after the shorter period in an enclosed composting system with addition of fertilizer and reuse of leachates. Most of the cuttings in this substrate died and only 4% of the cuttings rooted successfully. Physicochemical characteristics of this rooting medium included very high electrical conductivity, low C/N ratio and high water retention. Addition of coarse sand and pine bark compost to the composted gorse significantly increased the rooting success. The root quality variables differed depending on the substrate considered and date of harvest. The results showed that substrates made from gorse compost are of potential use as a peat substitute for propagating cuttings of T. plicata ‘Atrovirens’. The physicochemical properties of the composted gorse should be determined before its use to establish whether it can be used pure as a substrate for rooting or whether it should be mixed with other substances.     

蝴蝶兰组培苗对不同移栽基质的适应性

以蝴蝶兰组培苗为试材,研究了炭基肥和椰糠、水苔以不同比例混合对移栽前基质理化性质和移栽后基质理化性质、蝴蝶兰组培苗的生长特性的影响,以期为蝴蝶兰的栽培提供参考依据。结果表明:在椰糠和水苔中加入炭基肥,显著改变了基质的理化性质,提高了有机质、全氮、全磷和全钾含量。蝴蝶兰成活率提高了3.71%~10.18%,叶宽增加7.74%~25.54%,叶绿素含量和净光合速率显著提高。其中,椰糠和炭基肥以4∶1生长状况最好,水苔和炭基肥以6∶1生长状况最好,说明炭基肥在蝴蝶兰组培苗基质中的应用有显著效果。     

几种复合育苗基质特性及其在生菜上的育苗效果

将蛭石、炉渣灰、细砂、草炭和有机肥等按照不同组合与配比组成复合基质 ,用于生菜穴盘育苗。结果表明 ,不同基质对生菜幼苗生长影响有明显差异。复合基质T2 (蛭石∶有机肥∶炉渣灰 =7∶2∶1)育苗效果最佳 ,明显好于CK(草炭∶蛭石 =2∶1) ,表现为幼苗生长迅速 ,干物质积累快 ,壮苗指数大。因此 ,T2 可代替CK用于工厂化穴盘育苗 ,T3 、T7的育苗效果次于T2 ,而优于CK ,亦具有利用的价值     

不同配方基质对黄瓜幼苗生长的影响

研究了以锯末、菇渣为基本原料的不同基质配方对黄瓜幼苗生长发育的影响。结果表明,腐熟对锯末的理化性质有很大的影响;以腐熟锯末和菇渣育苗时,未发现出苗不齐和幼苗黄化现象;试验所用基质配方中,M3(60%锯末+30%菇渣+10%草炭)和M4(60%锯末+40%菇渣)是较好的黄瓜育苗无土基质配方。