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To compliment the current subirrigation systems used for production of potted plants, a nutrient-flow wick culture (NFW) system was developed and compared with other subirrigation systems, such as an ebb and flow culture (EBB) system and a nutrient-stagnant wick culture (NSW) system in relation to their system characteristics and plant growth. Kalanchoe (Kalanchoe blossfeldiana cv. New Alter) was cultivated in a 6 cm pot for 10 weeks in each subirrigation system. The water-absorption pattern of the medium, water content of the medium, water loss, algal growth, salt-buildup and plant growth under various culture systems were observed. The water contents of medium under the NFW and EBB systems showed fluctuations from 30 to 40% and from 50 to 60% (by volume), respectively, whereas the water content under the NSW system gradually increased to over 40% without fluctuation. Relative to other systems, the water loss in the NFW system was 50–70% due to the reduction in the evaporation from the surfaces of the trough and medium. Algae appeared in the NSW system because the nutrient solution was always stagnant in the trough, while it was not observed under the NFW system. The dissolved oxygen in the nutrient solution was the highest during the irrigation period and the salinity in the medium was the lowest in the NFW system. With regard to system characteristics, the NFW system was simple, water-saving and efficient. In addition, the growth of kalanchoes in the NFW system was similar to those in the NSW and EBB systems at an irrigation frequency of five times a day. 相似文献
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The oxygen (O2) content of flowing nutrient solutions was monitored periodically at various points along and across the gullies of a nutrient-film culture system (NFT). The O2 content of solution in which mature cucumber plants were growing was more depleted than that of those in which tomatoes were growing. In good weather there was a marked depletion of O2 in the nutrient solution as it flowed from the inlet to the lower end of gullies containing cucumber plants, which was not found in gullies with tomato plants. On sunny days, the O2 content of the solutions in which cucumbers were growing varied through the day at all points in the gullies and was lowest in the afternoons.A cucumber crop was grown from the seedling stage to maturity in 3 NFT gullies containing nutrient solutions with O2 contents controlled at different levels. Day-to-day variations in O2 content of the nutrient solutions were recorded throughout the duration of the experiment and the effects of these on the growth, development and yield of the plants was measured. Growth rates, root mass, root appearance, leaf area, water consumption and yield were reduced by low O2 levels in the nutrient solutions. 相似文献
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Susan L Steinberg Gerard J Kluitenberg Scott B Jones Nihad E Daidzic Lakshmi N Reddi Ming Xiao Markus Tuller Rebecca M Newman Dani Or J Iwan D Alexander 《Journal of the American Society for Horticultural Science》2005,130(5):767-774
Baked ceramic aggregates (fritted clay, arcillite) have been used for plant research both on the ground and in microgravity. Optimal control of water and air within the root zone in any gravity environment depends on physical and hydraulic properties of the aggregate, which were evaluated for 0.25-1-mm and 1-2-mm particle size distributions. The maximum bulk densities obtained by any packing technique were 0.68 and 0.64 g cm-3 for 0.25-1-mm and 1-2-mm particles, respectively. Wettable porosity obtained by infiltration with water was approximately 65%, substantially lower than total porosity of approximately 74%. Aggregate of both particle sizes exhibited a bimodal pore size distribution consisting of inter-aggregate macropores and intra-aggregate micropores, with the transition from macro- to microporosity beginning at volumetric water content of approximately 36% to 39%. For inter-aggregate water contents that support optimal plant growth there is 45% change in water content that occurs over a relatively small matric suction range of 0-20 cm H2O for 0.25-1-mm and 0 to -10 cm H2O for 1-2-mm aggregate. Hysteresis is substantial between draining and wetting aggregate, which results in as much as a approximately 10% to 20% difference in volumetric water content for a given matric potential. Hydraulic conductivity was approximately an order of magnitude higher for 1-2-mm than for 0.25-1-mm aggregate until significant drainage of the inter-aggregate pore space occurred. The large change in water content for a relatively small change in matric potential suggests that significant differences in water retention may be observed in microgravity as compared to earth. 相似文献
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Junqiang Li Yongqing Wang Lihua Lin Lijun Zhou Nan Luo Qunxian Deng Junren Xian Chunxia Hou Yuan Qiu 《Scientia Horticulturae》2008
The object of this study was to induce embryogenesis and establish plant regeneration system for anther culture in loquat (Eriobotrya japonica L.). Cold pretreatment was a key factor, and supplement of 2,4-D in the media was absolutely necessary for induction of calluses from cultured loquat anthers. The best response of anthers to in vitro culture was obtained when a 48-h cold pretreatment was employed to flower buds at 4 °C in darkness. Genotype was a decisive factor for embryo differentiation. When anther-derived calluses of three loquat cultivars, i.e., cv. ‘Longquan1’, ‘Dawuxing’ and ‘Zaozhong6’, were transferred to embryo differentiation medium, embryos were induced only for cv. ‘Dawuxing’ on MS medium containing 3% sucrose, 0.23 μM ZT in combination with 0.05 μM NAA + 0.05 μM IBA or 0.11 μM NAA + 0.10 μM IBA, and the differentiation rates were 3.33% and 10.00%, respectively. The results of histological studies showed that embryos developed through typical globular, heart, torpedo and cotyledon stages after 4 weeks of culture. The treatment designed to mature the embryos on medium containing 3% of sucrose at 4 °C under darkness for 4 weeks was effective for subsequent embryo germination and plant conversion, which gave rise to 72.5% plant recovery. Cytological studies showed that 26 plantlets were haploids (n = 17) and the remaining 4 plantlets were diploids for the 30 regenerants tested. 相似文献
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平菇病毒dsRNA的提取及脱除 总被引:1,自引:0,他引:1
以平菇为试材,采用改进SDS法从平菇组织中提取病毒特异dsRNA,并分别采用化学药剂-菌丝尖端处理和高温-菌丝尖端处理对平菇中的病毒进行了脱毒处理.结果表明:病毒dsRNA特点显示其与国外报道的平菇病毒dsRNA一致.其中高温-菌丝尖端脱除处理的效果最好,可有效脱除平菇病毒;病毒唑、放线菌酮及病毒唑与盐酸吗啉胍联合菌丝尖端脱除处理,可使病毒dsRNA条带减弱.该试验建立了从平菇组织中提取病毒dsRNA的技术体系,可有效对平菇中的病毒进行鉴定. 相似文献
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《Scientia Horticulturae》2005,106(1):129-134
Locust bean gum (LBG) is a natural hydrocolloid extracted from the seeds of carob tree (Ceratonia siliqua L.). This work describes the successful use of LBG as a gelling agent in combination with agar for shoot multiplication and rooting of carob tree and Iberian rose shoots. Its presence did not affect the multiplication rate of both species. The rooting frequency of carob shoots was even significantly increased in the presence of 5 g of LBG plus 4 g of agar to the medium compared to medium solidified with 9 g of agar. Iberian rose shoots rooting was not influenced by the addition of this gum to the rooting medium. Results obtained show that LBG can be used in combination with agar in culture medium as a gelling agent without negative effect on plant material and with the advantage of reduced medium costs. 相似文献
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Culture of citrus bud explants sampled from outdoor trees is sometimes difficult because of contamination not overcome by standard surface-sterilization. An improved method, involving a 5-minute immersion of explants in 80% (v/v) ethanol, which does not interfere with normal explant and callus development, is described in detail. 相似文献
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1“资脐一号”的选育过程
1990年资源县从华中农业大学引进纽荷尔、佛罗斯特和奈维林娜等5个国外脐橙品种嫁接苗定植于资源县农业局经作站脐橙品种试验园。1992年从该园取秋梢培育枳砧纽荷尔嫁接苗100株,1993年冬定植于延东乡修睦村石元琴、石元朗兄弟脐橙园中,1996年发现一株试挂果树的果实性状明显不同于其他植株的果实,表现为果大、皮深橙红色、光滑,果实长椭圆型,大小均匀,早熟。 相似文献
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AIM: To explore the effect of anthocyanin on cholesterol efflux and elucidate its possible molecular mechanism. METHODS: Mouse Peritoneal macrophages were loaded with 50 mg/L AcLDL to induce macrophage-derived foam cells. Cholesterol efflux from macrophage-derived foam cells induced by anthocyanin was determined by enzymatic methods. PPAR-γ mRNA and protein expression in macrophage-derived foam cells was assayed by quantitative PCR and western blotting. RESULTS: Anthocyanins had the capacity of promoting cholesterol efflux from mouse peritoneal macrophage-derived foam cells and increased PPAR-γ mRNA and protein expression. CONCLUSION: Anthocyain-induced cholesterol efflux may be related to its enhancing PPAR-γ mRNA and protein expression. 相似文献
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植物生长调节剂对紫果西番莲离体培养的影响 总被引:4,自引:0,他引:4
以紫果西番莲的茎段为外植体,以1/2MS为基础培养基,添加ZEA2-3mg/l,外植体萌芽率高达100%。不定芽在1/2MS培养基中,附加B A1.0 NAA0.1mg/l,其增殖系数最高。芽苗不定根的诱导培养基1/2MS+IBA1.5-2.3mg/l,其生根率较高,当IBA为2.5mg/l时芽苗生根率达100%。 相似文献
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国产蝴蝶兰种苗携带建兰花叶病毒(CymMV)和齿兰环斑病毒(ORSV)的调查及脱毒的初步研究 总被引:3,自引:0,他引:3
采用双抗夹心酶联免疫吸附法(DAS-ELISA)对国内不同蝴蝶兰种植场的17个蝴蝶兰分生苗品系种苗(22个样本)携带的2种主要病毒(CymMV和ORSV)的情况进行了检测调查,并采用茎尖培养和原球茎诱导的方式对携带病毒的4个蝴蝶兰品系进行了脱毒研究。结果表明:22个样本中有20个样本复合感染2种病毒,仅有1个样本显示了阴性结果。采用茎尖培养的‘R-2-2’和‘Y-4-2’品系,其脱毒率分别为22.7%(CymMV)和19.1%(ORSV),30.3%(CymMV)和8.0%(ORSV);采用原球茎脱毒的‘R-1-2’和‘R-11-1’品系,其脱毒率分别为25.4%(CymMV)和1.4%(ORSV),25.2%(CymMV)和24.2%(ORSV)。茎尖培养和原球茎诱导方式均不能一次性彻底脱毒。 相似文献
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F. Ortín-Párraga 《The Journal of Horticultural Science and Biotechnology》2013,88(5):624-628
SummaryYields of 106–107 apricot mesophyll protoplasts g fw–1 were obtained depending on factors such as plasmolysing pretreatment, digesting enzymes and digestion time. Onozuka R-10 (1%) in combination with Pectolyase Y-23 (0.1%) and Hemicellulase (1%) was found best for protoplast isolation among several enzyme combinations tested. Viability was 83% with this enzyme combination. Plasmolysis of leaves for 90 min in a 13% sorbitol solution greatly increased the number of protoplasts obtained. Optimum incubation time of 13–16 h produced the best combination of yield and viability. During the purification of protoplasts a critical step was the centrifugation of the sucrose gradient at 75 g with a dramatic decrease in the recovery of protoplasts at lower and higher centrifugation speeds. Protoplasts were cultured under different media composition and growth regulator combinations. Limited growth and division of protoplasts embedded in agarose drops were obtained. 相似文献
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