With the rising pressures on food security, GREENBOX technology was developed as an avenue for fresh leafy vegetable crop production in urban settings. GREENBOX units were designed to be thermally insulated and climat...With the rising pressures on food security, GREENBOX technology was developed as an avenue for fresh leafy vegetable crop production in urban settings. GREENBOX units were designed to be thermally insulated and climate controlled, with an artificial lighting source that utilized soilless cultivation techniques. Previous studies conducted on GREENBOX technology used the Nutrient Film Technique (NFT);however, various hydroponic methods exist, such as the Deep-Water Culture (DWC) method being the most used. The APS Laboratory for Sustainable Food at Florida Gulf Coast University (FGCU) compared the crop growth performance between DWC and NFT systems using GREENBOX technology. The following study monitored environmental conditions and compared productivity and biomass data of Rex Butterhead Lettuce crops between DWC and NFT systems. We assembled two GREENBOX units using commercially available materials and the standard nutrient solution for fertigation. The crops grown in DWC and NFT were in a 4 × 6 configuration. The DWC and NFT systems were used to grow Lettuce Lactuca sativa “Rex Butterhead” over 30 days to full bloom from prepared plugs grown for 14 days. We collected environmental data including Photosynthetic Photon Flux Density (PPFD, μmol/m<sup>2</sup>∙s), Daily Light Integral (DLI, mol/ m<sup>2</sup>∙d), temperature (˚C), relative humidity (%), and Vapor Pressure Deficit (VPD, kPa). We collected lettuce crop growth data, which included wet weight (g), dry weight (g), leaf area (cm<sup>2</sup>), and chlorophyll concentration (μmol/m<sup>2</sup>). We derived data, including the Specific Leaf Area (SLA, cm<sup>2</sup>/g) and biomass productivity (kg/m<sup>2</sup>), from previously collected data. We used descriptive statistics to present the collected data. A paired t-test was performed to understand the differences in biomass and productivity parameters between the DWC and NFT-grown lettuce crops. Both the DWC and NFT-grown crops could grow lettuce crops to harvest weight at full bloom. Observed data demonstrated that the biomass parameters and productivity did not differ significantly between the two hydroponics techniques. Therefore, we believe both hydroponic methods may be similar in growth performance and may be used in future iterations of GREENBOX design and prove suitable for fresh vegetable crop production in urban settings.展开更多
Conventional soil-based agriculture is resource-intensive, utilizing large amounts of land and water, thereby placing a strain on Earth’s natural resources. Soil-based agricultural techniques create environmental iss...Conventional soil-based agriculture is resource-intensive, utilizing large amounts of land and water, thereby placing a strain on Earth’s natural resources. Soil-based agricultural techniques create environmental issues such as soil degradation, deforestation, and groundwater pollution from the mass implementation of fertilizers and pesticides. Agricultural crop production using hydroponics has shown promise to be less resource intensive and provide a faster turnaround in crop production. Soilless cultivation using hydroponics promises to relieve some pressure on Earth’s ecosystems and resources by utilizing lesser land and water footprint. The APS Laboratory for Sustainable Food at Florida Gulf Coast University (FGCU) compared the growth of Lettuce Lactuca sativa “Rex Butterhead” crop grown using soil and soilless methods to analyze the growth performance in each setting. Crops grown in the soil-based medium were raised in the FGCU Food Forest, used a mix of soil and potting mix, watered regularly, and followed standard Integrated Pest Management (IPM) practices. Crops grown hydroponically were grown in a thermally insulated grow tent with an artificial lighting source, ventilation, environmental controls, and the Deep-Water Culture (DWC) method. Lettuce plugs were grown for 15 days in controlled environments until two leaves after the cotyledons had developed and were ready for transplant. Plugs were transplanted into a 4 × 6 matrix at the FGCU Food Forest and the DWC growth system. Crops were grown to full bloom and ready for harvest in the soil (60 days) and soilless (30 days) based setups. We collected crop growth data, including wet weight (g), dry weight (g), leaf area (cm<sup>2</sup>), and chlorophyll concentration (μmol/m<sup>2</sup>). From the collected data, we derived the Specific Leaf Area (SLA, cm<sup>2</sup>/g) and biomass productivity (kg/m<sup>2</sup>). Descriptive statistics were used to describe the collected and derived data. We investigated the slopes of regression lines for each growth curve which derived the differences in biomass and productivity parameters between lettuce grown using soil and hydroponics. Both growing methods can grow lettuce crops to full bloom and to adequate harvest weight. The biomass parameters and productivity differ significantly between the growing methods. The lettuce crops grown using hydroponics increase in wet weight statistically and significantly faster than those grown in soil (p < 0.0001). Therefore, we determined that a hydroponic method of crop production may provide better crop output and biomass indicators measured than soil-based growth.展开更多
[Objective] The experiment aimed to study the growth characteristics of hydroponic bowl lotus. [Method] The lotus variety Hongxia was chosen as the experimental material. Two treatments, hydroponics and soil culture w...[Objective] The experiment aimed to study the growth characteristics of hydroponic bowl lotus. [Method] The lotus variety Hongxia was chosen as the experimental material. Two treatments, hydroponics and soil culture were set to measure their photosynthetic indices, chlorophyll content and root vigor, and to observe their leaf tissue structure and stomatal characteristics. [Result] The findings indicated that there are no differences in the leaf physiological indices between bowl lotus under hydroponics and soil culture, while the leaf stomata of hydroponic bowl lotus is bigger and its amount is larger than that of soil-culture bowl lotus. At the same time, the ratio of the palisade tissue thickness to spongy tissue thickness is small,and its leaf tissue structure is loose. The root vigor of hydroponic bowl lotus reached its summit earlier, then began to drop. Whereas, the root activity of soil-culture lotus sustained increasing, with vigorous growth. [Conclusion] Therefore, it indicated that hydroponic bowl lotus can adapt to the aquatic-culture environment well and quickly, meanwhile, it also enters into its aging period quickly and its growth cycle gets shorter.展开更多
Vertical flow constructed wetlands is a typical ecological sanitation system for sewage treatment. The removal rates for COD, BOD 5, SS, TN, and TP were 60%, 80%, 74%, 49% and 79%, respectively, when septic tank effl...Vertical flow constructed wetlands is a typical ecological sanitation system for sewage treatment. The removal rates for COD, BOD 5, SS, TN, and TP were 60%, 80%, 74%, 49% and 79%, respectively, when septic tank effluent was treated by vertical flow filter. So the concentration of COD and BOD\-5 in the treated effluent could meet the quality standard for irrigation water. After that the treated effluent was used for hydroponic cultivation of water spinach and romaine lettuce, the removal efficiencies of the whole system for COD, BOD\-5, SS, TN and TP were 71 4%, 97 5%, 96 9%, 86 3%, and 87 4%, respectively. And it could meet the integrated wastewater discharge standard for secondary biological treatment plant. It was found that using treated effluent for hydroponic cultivation of vegetables could reduce the nitrate content in vegetables. The removal rates for total bacteria and coliform index by using vertical flow bed system with cinder substrate were 80%—90% and 85%—96%, respectively.展开更多
Screening cultivars to grow under conditions of low phosphorus (P) availability and utilize P efficiently from compounds of low solubility in soils may be beneficial to overcome poor plant growth in P-deficient soils....Screening cultivars to grow under conditions of low phosphorus (P) availability and utilize P efficiently from compounds of low solubility in soils may be beneficial to overcome poor plant growth in P-deficient soils. The growth behavior and P utilization efficiency of seven wheat cultivars grown in hydroponics were studied, using rock phosphate as P source. The wheat cultivars grown for 30 days were significantly different in biomass accumulation, P uptake and P utilization efficiency. The dry matter production of all the cultivars was significantly correlated with P uptake, which in turn correlated to the drop in the root medium pH. The ranking of wheat cultivars on the basis of dry matter yield, P uptake and P utilization efficiency was Zamindar 80 > Yecora > C 271 > WL 711 > Barani 83 > PARI 73 > Rohtas. The cultivar Zamindar 80 appeared to possess the best growth potential in P-deficient soils.展开更多
The coupling effect of nutrient solution EC (electrical conductivity) levels and CR (circulation rate) on the morphology and quality, in hydroponically grown lettuce was assessed. Lettuce was grown at 5 treatments...The coupling effect of nutrient solution EC (electrical conductivity) levels and CR (circulation rate) on the morphology and quality, in hydroponically grown lettuce was assessed. Lettuce was grown at 5 treatments fi'om High EC & Low CR to Low EC & High CR. The environmental parameters were controlled in a 20 m^2 plant factory during the hydroponic cultivation with the following values: irradiated by blue and red light-emitting diode lighting with PPFD (photosynthetic photon flux density) value of 150 mol·m^-2·s^-1 for 16 hours per day; Temperature was maintained at 22.0 ℃ during the photoperiod and 16.0 ℃ in dark cycle. The results demonstrate that growing lettuce can be adopted using nutrient solution with lower EC levels and higher CR. The results also indicate that the effect of bi-directional coupled EC and CR resulted in expansion of root length but reducing the root biomass. Nitrate content was significantly reduced.展开更多
A novel form of hydroponic culture was employed to explore the physiological function of roots of a tea plant (Camellia sinensis). The pH of the nutrient solution with an actively growing tea plant decreased during cu...A novel form of hydroponic culture was employed to explore the physiological function of roots of a tea plant (Camellia sinensis). The pH of the nutrient solution with an actively growing tea plant decreased during cultivation. Furthermore, no oxalic acid, tartaric acid, malic acid or citric acid, all possible factors in acidification, was detected in the nutrient solution of a growing plant. A proton pump inhibitor suppressed the acidification of the solution. Soil acidification might have been accelerated with a proton released from ammoniacal nitrogen preferentially for the growth, suggesting the specific mechanism of tea plant as a functional food.展开更多
<i><span style="font-family:"">Morus alba </span></i><span style="font-family:"">L<i>.,</i></span><span style="font-family:"&q...<i><span style="font-family:"">Morus alba </span></i><span style="font-family:"">L<i>.,</i></span><span style="font-family:""> (cv Ichinose) was cultivated by in-room hydroponics. The flavor and texture of leaves were markedly improved enough to be edible. When the contents of 1-deoxynojirimycin (DNJ) and polyphenols were measured in the hydroponic cultivar, DNJ increased in the leaf compared to the field grown <i>M. alba</i>. However, polyphenols, in contrast, decreased compared to the field cultivar. HPLC profiling revealed marked difference in leaf components between hydroponic and field cultivars indicating relative contents of lipo<span>philic polyphenols were increased. The polyphenols contents, especially, li</span>po<span>philic polyphenols in the root were remarkably high compared to So-Haku-Hi (Sang Bai Pi in Chinese).</span> The anti-obesity effect of the hydroponically grown <i>Morus</i> was further studied in rats by feeding high-fat, high-sucrose (HFHS) diet with and without supplementation of dried leaf and root powders for 15 weeks. As the result, both the leaf and root from the hydroponic cultivar showed potential anti-obesity and anti-hyperlipidemic functions through amelioration of insulin resistance. Differential effects of leaf and root powders indicated that besides DNJ, the lipophilic polyphenols may play a crucial role in the anti-diabetic function of hydroponically grown <i>Morus alba </i>L. The hydroponics will provide an alternate way to cultivate a novel resource of <i>Morus</i> for developing functional foods and medicines.展开更多
The study aimed to develop a vertical crop cultivation system for leafy plants based on cylindrical hydroponics and light emitting diode (LED) technology. Investigations were conducted on growing lettuce (Lactuca s...The study aimed to develop a vertical crop cultivation system for leafy plants based on cylindrical hydroponics and light emitting diode (LED) technology. Investigations were conducted on growing lettuce (Lactuca sativa cv. "Rex", "Nanda" and "Canasta") indoors in a rotary system and Chinese cabbage (Brassica chinensis) in a multi-tier cylindrical hydroponics system under red and blue (RB) LED lightings. Light intensity from different light sources have an influence on the yield and growth behaviour of indoor lettuce. Photosynthetically active radiation (PAR) levels at 63 μmol/m2·s produced low fresh weights (FW) and leaf areas of lettuce "Rex" and "Nanda" were grown under rotating conditions. The effect was, however, different on the better developed "Canasta". Stem etiolation was a common occurrence under such influence. Chlorosis was not observed on all plant types grown under the LEDs. Cultivating Chinese cabbage plants (FW: 28 g/plant) in cylindrical units stacked vertically above another, increased planting density by 47% when compared to the rotary system,展开更多
Hydroponic culture is a controlled systems use a soilless growing media,supply all of the plant’s nutrition in the plant’s solutions(water with dissolved fertilizers),result in higher yields of vegetables,flowers,he...Hydroponic culture is a controlled systems use a soilless growing media,supply all of the plant’s nutrition in the plant’s solutions(water with dissolved fertilizers),result in higher yields of vegetables,flowers,herbs and others crops.Hydroponic systems derive in many various forms and types.Most traditional hydroponic systems are extremely specialized,controlled-environment production systems.Organic hydroponics is a system that is arranged based on organic agriculture of culture.Different approaches are used for controlling of plant pathogens such as physical,chemical,biological controls,biofertilizers,bioremediators and integrated pest management.All the required nutrients are supplied in controlled amounts,including organic crops.This article discuss the way for promoting organic hydroponics systems and to help the small-scale producer make decisions about follow this markets,production methods,and disease control.展开更多
Hydroponic farming is a viable and economical farming method,which can produce safe and healthy greens and vegetables conveniently and at a relatively low cost.It is essential to provide supplemental lighting for crop...Hydroponic farming is a viable and economical farming method,which can produce safe and healthy greens and vegetables conveniently and at a relatively low cost.It is essential to provide supplemental lighting for crops grown in greenhouses to meet the daily light requirement,Daily Light Integral(DLI).The present paper investigates how effectively and efficiently LEDs can be used as a light source in hydroponics.It is important for a hydroponic grower to assess the requirement of photo synthetically active radiation(PAR)or the Photosynthetic Photon Flux Density(PPFD),in a greenhouse,and adjust the quality and quantity of supplemental lighting accordingly.A Quantum sensor(or PAR sensor)can measure PAR more accurately than a digital light meter,which measures the light intensity or illuminance in the SI unit Lux,but a PAR sensor is relatively expensive and normally not affordable by an ordinary farmer.Therefore,based on the present investigation and experimental results,a very simple way to convert light intensity measured with a Lux meter into PAR is proposed,using a simple conversion factor(41.75 according to the present work).This allows a small-scale hydroponic farmer to use a simple and inexpensive technique to assess the day to day DLI values of PAR in a greenhouse accurately using just an inexpensive light meter.The present paper also proposes a more efficient way of using LED light panels in a hydroponic system.By moving the LED light panels closer to the crop,LED light source can use a fewer number of LEDs to produce the same required daily light requirement and can increase the efficiency of the power usage to more than 80%.Specifically,the present work has determined that it is important to design more efficient vertically movable LED light panels with capabilities of switching individual LEDs on and off,for the use in greenhouses.This allows a user to control the number of LEDs that can be lit at a particular time,as required.By doing so it is possible to increase the efficiency of a LED lighting system by reducing its cost of the electricity usage.展开更多
为实现水培营养液水质参数的高效、精确控制,减少设备供能产生的碳排量,构建了一个基于粒子群优化(Particle Swarm Optimization,PSO)算法和最大功率点跟踪(Maximum Power Point Tracking,MPPT)算法的水培智能控制系统。用PSO算法优化...为实现水培营养液水质参数的高效、精确控制,减少设备供能产生的碳排量,构建了一个基于粒子群优化(Particle Swarm Optimization,PSO)算法和最大功率点跟踪(Maximum Power Point Tracking,MPPT)算法的水培智能控制系统。用PSO算法优化模糊控制器的量化、比例因子,加入Smith预估器补偿反馈时延,对pH为4.5、电导率(Electrical Conductivity,EC)为0 mS/cm的营养液进行精确调控。经过优化,分别在44 s和43 s后达到预设值,并能维持稳定状态。建立光伏发电模块,引入MPPT算法,缩短跟踪时长至0.04 s。结果表明,该系统能提高营养液水质参数的调节精度,缩短控制时长,增强水培环境的稳定性;同时,能提升发电效率,实现节能减排。展开更多
为明确海巴戟幼苗对盐的耐受范围及盐胁迫对海巴戟幼苗生长的影响,以水培180d的海巴戟苗为材料,基本培养基为1/8 MS液体培养基,其中分别加入质量分数为0、0.2%、0.4%、0.6%、0.8%和1.0%的NaCl进行胁迫处理。结果表明:随着NaCl胁迫浓度...为明确海巴戟幼苗对盐的耐受范围及盐胁迫对海巴戟幼苗生长的影响,以水培180d的海巴戟苗为材料,基本培养基为1/8 MS液体培养基,其中分别加入质量分数为0、0.2%、0.4%、0.6%、0.8%和1.0%的NaCl进行胁迫处理。结果表明:随着NaCl胁迫浓度的增加与胁迫时间的推移,海巴戟叶片相对含水量(relative water content,RWC)与生物量逐渐降低,可溶性蛋白(solubleprotein,SP)、丙二醛(MDA)的含量以及超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、抗坏血酸过氧化物酶(APX)、过氧化物酶(POD)活性均表现为先增加后减少的趋势。海巴戟幼苗的保护酶活性随着NaCl胁迫浓度的增加与胁迫时间的推移发生显著变化,在NaCl浓度0.8%以下范围,海巴戟可以通过调节渗透物质和抗氧化物酶来减轻伤害,保证生长;当NaCl浓度在0.8%及以上范围时,保护酶系统与细胞膜受损严重,进而影响海巴戟生长。因此,海巴戟幼苗可以在0.8%以下NaCl浓度范围的区域试种。展开更多
文摘With the rising pressures on food security, GREENBOX technology was developed as an avenue for fresh leafy vegetable crop production in urban settings. GREENBOX units were designed to be thermally insulated and climate controlled, with an artificial lighting source that utilized soilless cultivation techniques. Previous studies conducted on GREENBOX technology used the Nutrient Film Technique (NFT);however, various hydroponic methods exist, such as the Deep-Water Culture (DWC) method being the most used. The APS Laboratory for Sustainable Food at Florida Gulf Coast University (FGCU) compared the crop growth performance between DWC and NFT systems using GREENBOX technology. The following study monitored environmental conditions and compared productivity and biomass data of Rex Butterhead Lettuce crops between DWC and NFT systems. We assembled two GREENBOX units using commercially available materials and the standard nutrient solution for fertigation. The crops grown in DWC and NFT were in a 4 × 6 configuration. The DWC and NFT systems were used to grow Lettuce Lactuca sativa “Rex Butterhead” over 30 days to full bloom from prepared plugs grown for 14 days. We collected environmental data including Photosynthetic Photon Flux Density (PPFD, μmol/m<sup>2</sup>∙s), Daily Light Integral (DLI, mol/ m<sup>2</sup>∙d), temperature (˚C), relative humidity (%), and Vapor Pressure Deficit (VPD, kPa). We collected lettuce crop growth data, which included wet weight (g), dry weight (g), leaf area (cm<sup>2</sup>), and chlorophyll concentration (μmol/m<sup>2</sup>). We derived data, including the Specific Leaf Area (SLA, cm<sup>2</sup>/g) and biomass productivity (kg/m<sup>2</sup>), from previously collected data. We used descriptive statistics to present the collected data. A paired t-test was performed to understand the differences in biomass and productivity parameters between the DWC and NFT-grown lettuce crops. Both the DWC and NFT-grown crops could grow lettuce crops to harvest weight at full bloom. Observed data demonstrated that the biomass parameters and productivity did not differ significantly between the two hydroponics techniques. Therefore, we believe both hydroponic methods may be similar in growth performance and may be used in future iterations of GREENBOX design and prove suitable for fresh vegetable crop production in urban settings.
文摘Conventional soil-based agriculture is resource-intensive, utilizing large amounts of land and water, thereby placing a strain on Earth’s natural resources. Soil-based agricultural techniques create environmental issues such as soil degradation, deforestation, and groundwater pollution from the mass implementation of fertilizers and pesticides. Agricultural crop production using hydroponics has shown promise to be less resource intensive and provide a faster turnaround in crop production. Soilless cultivation using hydroponics promises to relieve some pressure on Earth’s ecosystems and resources by utilizing lesser land and water footprint. The APS Laboratory for Sustainable Food at Florida Gulf Coast University (FGCU) compared the growth of Lettuce Lactuca sativa “Rex Butterhead” crop grown using soil and soilless methods to analyze the growth performance in each setting. Crops grown in the soil-based medium were raised in the FGCU Food Forest, used a mix of soil and potting mix, watered regularly, and followed standard Integrated Pest Management (IPM) practices. Crops grown hydroponically were grown in a thermally insulated grow tent with an artificial lighting source, ventilation, environmental controls, and the Deep-Water Culture (DWC) method. Lettuce plugs were grown for 15 days in controlled environments until two leaves after the cotyledons had developed and were ready for transplant. Plugs were transplanted into a 4 × 6 matrix at the FGCU Food Forest and the DWC growth system. Crops were grown to full bloom and ready for harvest in the soil (60 days) and soilless (30 days) based setups. We collected crop growth data, including wet weight (g), dry weight (g), leaf area (cm<sup>2</sup>), and chlorophyll concentration (μmol/m<sup>2</sup>). From the collected data, we derived the Specific Leaf Area (SLA, cm<sup>2</sup>/g) and biomass productivity (kg/m<sup>2</sup>). Descriptive statistics were used to describe the collected and derived data. We investigated the slopes of regression lines for each growth curve which derived the differences in biomass and productivity parameters between lettuce grown using soil and hydroponics. Both growing methods can grow lettuce crops to full bloom and to adequate harvest weight. The biomass parameters and productivity differ significantly between the growing methods. The lettuce crops grown using hydroponics increase in wet weight statistically and significantly faster than those grown in soil (p < 0.0001). Therefore, we determined that a hydroponic method of crop production may provide better crop output and biomass indicators measured than soil-based growth.
基金Supported by Key Scientific and Technological Project of Henan Province(072102150001)~~
文摘[Objective] The experiment aimed to study the growth characteristics of hydroponic bowl lotus. [Method] The lotus variety Hongxia was chosen as the experimental material. Two treatments, hydroponics and soil culture were set to measure their photosynthetic indices, chlorophyll content and root vigor, and to observe their leaf tissue structure and stomatal characteristics. [Result] The findings indicated that there are no differences in the leaf physiological indices between bowl lotus under hydroponics and soil culture, while the leaf stomata of hydroponic bowl lotus is bigger and its amount is larger than that of soil-culture bowl lotus. At the same time, the ratio of the palisade tissue thickness to spongy tissue thickness is small,and its leaf tissue structure is loose. The root vigor of hydroponic bowl lotus reached its summit earlier, then began to drop. Whereas, the root activity of soil-culture lotus sustained increasing, with vigorous growth. [Conclusion] Therefore, it indicated that hydroponic bowl lotus can adapt to the aquatic-culture environment well and quickly, meanwhile, it also enters into its aging period quickly and its growth cycle gets shorter.
文摘Vertical flow constructed wetlands is a typical ecological sanitation system for sewage treatment. The removal rates for COD, BOD 5, SS, TN, and TP were 60%, 80%, 74%, 49% and 79%, respectively, when septic tank effluent was treated by vertical flow filter. So the concentration of COD and BOD\-5 in the treated effluent could meet the quality standard for irrigation water. After that the treated effluent was used for hydroponic cultivation of water spinach and romaine lettuce, the removal efficiencies of the whole system for COD, BOD\-5, SS, TN and TP were 71 4%, 97 5%, 96 9%, 86 3%, and 87 4%, respectively. And it could meet the integrated wastewater discharge standard for secondary biological treatment plant. It was found that using treated effluent for hydroponic cultivation of vegetables could reduce the nitrate content in vegetables. The removal rates for total bacteria and coliform index by using vertical flow bed system with cinder substrate were 80%—90% and 85%—96%, respectively.
文摘Screening cultivars to grow under conditions of low phosphorus (P) availability and utilize P efficiently from compounds of low solubility in soils may be beneficial to overcome poor plant growth in P-deficient soils. The growth behavior and P utilization efficiency of seven wheat cultivars grown in hydroponics were studied, using rock phosphate as P source. The wheat cultivars grown for 30 days were significantly different in biomass accumulation, P uptake and P utilization efficiency. The dry matter production of all the cultivars was significantly correlated with P uptake, which in turn correlated to the drop in the root medium pH. The ranking of wheat cultivars on the basis of dry matter yield, P uptake and P utilization efficiency was Zamindar 80 > Yecora > C 271 > WL 711 > Barani 83 > PARI 73 > Rohtas. The cultivar Zamindar 80 appeared to possess the best growth potential in P-deficient soils.
文摘The coupling effect of nutrient solution EC (electrical conductivity) levels and CR (circulation rate) on the morphology and quality, in hydroponically grown lettuce was assessed. Lettuce was grown at 5 treatments fi'om High EC & Low CR to Low EC & High CR. The environmental parameters were controlled in a 20 m^2 plant factory during the hydroponic cultivation with the following values: irradiated by blue and red light-emitting diode lighting with PPFD (photosynthetic photon flux density) value of 150 mol·m^-2·s^-1 for 16 hours per day; Temperature was maintained at 22.0 ℃ during the photoperiod and 16.0 ℃ in dark cycle. The results demonstrate that growing lettuce can be adopted using nutrient solution with lower EC levels and higher CR. The results also indicate that the effect of bi-directional coupled EC and CR resulted in expansion of root length but reducing the root biomass. Nitrate content was significantly reduced.
文摘A novel form of hydroponic culture was employed to explore the physiological function of roots of a tea plant (Camellia sinensis). The pH of the nutrient solution with an actively growing tea plant decreased during cultivation. Furthermore, no oxalic acid, tartaric acid, malic acid or citric acid, all possible factors in acidification, was detected in the nutrient solution of a growing plant. A proton pump inhibitor suppressed the acidification of the solution. Soil acidification might have been accelerated with a proton released from ammoniacal nitrogen preferentially for the growth, suggesting the specific mechanism of tea plant as a functional food.
文摘<i><span style="font-family:"">Morus alba </span></i><span style="font-family:"">L<i>.,</i></span><span style="font-family:""> (cv Ichinose) was cultivated by in-room hydroponics. The flavor and texture of leaves were markedly improved enough to be edible. When the contents of 1-deoxynojirimycin (DNJ) and polyphenols were measured in the hydroponic cultivar, DNJ increased in the leaf compared to the field grown <i>M. alba</i>. However, polyphenols, in contrast, decreased compared to the field cultivar. HPLC profiling revealed marked difference in leaf components between hydroponic and field cultivars indicating relative contents of lipo<span>philic polyphenols were increased. The polyphenols contents, especially, li</span>po<span>philic polyphenols in the root were remarkably high compared to So-Haku-Hi (Sang Bai Pi in Chinese).</span> The anti-obesity effect of the hydroponically grown <i>Morus</i> was further studied in rats by feeding high-fat, high-sucrose (HFHS) diet with and without supplementation of dried leaf and root powders for 15 weeks. As the result, both the leaf and root from the hydroponic cultivar showed potential anti-obesity and anti-hyperlipidemic functions through amelioration of insulin resistance. Differential effects of leaf and root powders indicated that besides DNJ, the lipophilic polyphenols may play a crucial role in the anti-diabetic function of hydroponically grown <i>Morus alba </i>L. The hydroponics will provide an alternate way to cultivate a novel resource of <i>Morus</i> for developing functional foods and medicines.
文摘The study aimed to develop a vertical crop cultivation system for leafy plants based on cylindrical hydroponics and light emitting diode (LED) technology. Investigations were conducted on growing lettuce (Lactuca sativa cv. "Rex", "Nanda" and "Canasta") indoors in a rotary system and Chinese cabbage (Brassica chinensis) in a multi-tier cylindrical hydroponics system under red and blue (RB) LED lightings. Light intensity from different light sources have an influence on the yield and growth behaviour of indoor lettuce. Photosynthetically active radiation (PAR) levels at 63 μmol/m2·s produced low fresh weights (FW) and leaf areas of lettuce "Rex" and "Nanda" were grown under rotating conditions. The effect was, however, different on the better developed "Canasta". Stem etiolation was a common occurrence under such influence. Chlorosis was not observed on all plant types grown under the LEDs. Cultivating Chinese cabbage plants (FW: 28 g/plant) in cylindrical units stacked vertically above another, increased planting density by 47% when compared to the rotary system,
文摘Hydroponic culture is a controlled systems use a soilless growing media,supply all of the plant’s nutrition in the plant’s solutions(water with dissolved fertilizers),result in higher yields of vegetables,flowers,herbs and others crops.Hydroponic systems derive in many various forms and types.Most traditional hydroponic systems are extremely specialized,controlled-environment production systems.Organic hydroponics is a system that is arranged based on organic agriculture of culture.Different approaches are used for controlling of plant pathogens such as physical,chemical,biological controls,biofertilizers,bioremediators and integrated pest management.All the required nutrients are supplied in controlled amounts,including organic crops.This article discuss the way for promoting organic hydroponics systems and to help the small-scale producer make decisions about follow this markets,production methods,and disease control.
文摘Hydroponic farming is a viable and economical farming method,which can produce safe and healthy greens and vegetables conveniently and at a relatively low cost.It is essential to provide supplemental lighting for crops grown in greenhouses to meet the daily light requirement,Daily Light Integral(DLI).The present paper investigates how effectively and efficiently LEDs can be used as a light source in hydroponics.It is important for a hydroponic grower to assess the requirement of photo synthetically active radiation(PAR)or the Photosynthetic Photon Flux Density(PPFD),in a greenhouse,and adjust the quality and quantity of supplemental lighting accordingly.A Quantum sensor(or PAR sensor)can measure PAR more accurately than a digital light meter,which measures the light intensity or illuminance in the SI unit Lux,but a PAR sensor is relatively expensive and normally not affordable by an ordinary farmer.Therefore,based on the present investigation and experimental results,a very simple way to convert light intensity measured with a Lux meter into PAR is proposed,using a simple conversion factor(41.75 according to the present work).This allows a small-scale hydroponic farmer to use a simple and inexpensive technique to assess the day to day DLI values of PAR in a greenhouse accurately using just an inexpensive light meter.The present paper also proposes a more efficient way of using LED light panels in a hydroponic system.By moving the LED light panels closer to the crop,LED light source can use a fewer number of LEDs to produce the same required daily light requirement and can increase the efficiency of the power usage to more than 80%.Specifically,the present work has determined that it is important to design more efficient vertically movable LED light panels with capabilities of switching individual LEDs on and off,for the use in greenhouses.This allows a user to control the number of LEDs that can be lit at a particular time,as required.By doing so it is possible to increase the efficiency of a LED lighting system by reducing its cost of the electricity usage.
文摘为明确海巴戟幼苗对盐的耐受范围及盐胁迫对海巴戟幼苗生长的影响,以水培180d的海巴戟苗为材料,基本培养基为1/8 MS液体培养基,其中分别加入质量分数为0、0.2%、0.4%、0.6%、0.8%和1.0%的NaCl进行胁迫处理。结果表明:随着NaCl胁迫浓度的增加与胁迫时间的推移,海巴戟叶片相对含水量(relative water content,RWC)与生物量逐渐降低,可溶性蛋白(solubleprotein,SP)、丙二醛(MDA)的含量以及超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、抗坏血酸过氧化物酶(APX)、过氧化物酶(POD)活性均表现为先增加后减少的趋势。海巴戟幼苗的保护酶活性随着NaCl胁迫浓度的增加与胁迫时间的推移发生显著变化,在NaCl浓度0.8%以下范围,海巴戟可以通过调节渗透物质和抗氧化物酶来减轻伤害,保证生长;当NaCl浓度在0.8%及以上范围时,保护酶系统与细胞膜受损严重,进而影响海巴戟生长。因此,海巴戟幼苗可以在0.8%以下NaCl浓度范围的区域试种。