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Inadequate fertilization affects the production of quality seedlings, because they need a balanced balance of essential nutrients, in the concentrations required to grow properly. With the above, it was proposed to determine the effect produced by fertilizers calcium triple superphosphate, ammonium nitrate and potassium nitrate fertilizers on the variables number of leaves, plant height, plant diameter, root length and root biomass wet seedlings of Eucalyptus deglupta Blume (Myrtaceae). For this, three nutritional schemes were established of N, P, K and Ca (190-35-210-150 ppm) T1; (150-50-250-180ppm) T2; (140-55-300-200 ppm) T3 and a control without T4 solution. After 60 days, the concentrations of N, P, K and Ca (190-35-210-150 ppm) determined greater growth in the number of leaves (22,3 leaves); plant height (157,26 mm); plant diameter (2,41 mm) and wet root biomass (6,6 g). However, the observations indicate that for the root length variable, the treatments supplied with concentrations of N, P, K and Ca, did not show significant differences in their means. [ABSTRACT FROM AUTHOR]

Based on the example of an automated module of a vertical farm for growing plants, an author's method for developing automated devices using modern microcontrollers and a high-level microPython programming language is proposed. Additive technology as a method of "rapid prototyping" made it possible to effectively solve the issue of creating the main components of the module. The works on designing, assembling, and adjusting the experimental setup were carried out using modern methods and approaches for the industrial development of devices. The automated system makes it possible to solve the problems of lack and selection of the correct dosage of nutrients necessary for plants, controls, and minimizes water consumption, the root system develops fully. These factors make it possible to grow an adult plant in a short time without human participation. The apparatus can be used for organizing research activities in the subject areas of the natural science cycle, for greening in corridors and classrooms, and growing fresh herbs. [ABSTRACT FROM AUTHOR]

Seed germination improves the nutritional quality of plant foods; since they increase the contents and availability of essential nutrients and reduce the levels of antinutrients. A considerable number of species have been studied, but to date, there are few studies on vegetable species of the neo-tropics. The aim of this study was the evaluation and optimization of mineral nutrient solutions [Adelusi-Oseni (AO), Ruakura (Ru), Maeda (M)] and their combinations with compost extracts (EC1, EC2, and EC3) obtained from three different solvents, on the development of biomass of four neo-tropical vegetable plants in Mexico: pumpkin (Cucurbita pepo L.), papalo [Porophyllum ruderale (Jacq.) Cass.], pipitea (Porophyllum linaria Cav.), and purslane (Portulaca oleracea L.). The hypothesis was that biomass production achieved with the nutrient solutions would lead to the highest yield for each seed compared to the control. Germination was carried out in Petri dishes with cotton pads as substrate, adding 5 mL of nutrient solution, along with a control grown with water, in a photoperiod of 12 h; continuing germination until completing 96 h. San Cristóbal experimental design was applied to the nutrient mixtures with the greatest positive impact on the production of biomass. An ANOVA was carried out with Tukey and Dunnet means comparison tests. For pumpkin sprouts, solution EC3E2 managed to increase seedling growth by 395.2 % in comparison to the control; EC2A displayed a greater elongation in comparison with the control of 84.7 % for papal sprouts; EC2A produced an increase of 15.8 % in pipitea. In purslane, EC2A produced an increase of 53.7 %. Nutrition with compost extracts can favour the production of biomass from sprouts. [ABSTRACT FROM AUTHOR]

Introduction: Proper nutrition in the cultivation of cut flowers, including polianthes is extremely important. It is necessary to achieve quantitative and qualitative standards for the cultivation and production of this flower. It has been shown that, due to the lack of many secondary roots and shallow roots, the bulb plants are more sensitive to the lack of nutrients (such as phosphorus) compared to the other horticultural and agricultural crops. Plant growth regulators are particularly important in increasing the quantity and quality of flowers and ornamental plants, one of the most important of which is the positive effects of gibberellins in ornamental plants. Phosphorus (P) plays a key role in photosynthetic activities, flower formation and production of reproductive organs of greenhouse crops. The present study will examine the effects of gibberellin as a plant growth regulators and different concentrations of phosphorus) on the growth characteristics and flowering indices of marigold under hydroponic conditions. Material and methods: An experiment was implemented to investigate the effect of gibberellic acid and various concentrations of P in nutrient solution on the growth and flowering of polianthes. The experiment was factorial based on a randomized complete block design with three replicates. The cuttings were immersed in 0 (distilled water), 100 and 200 mg/L of gibberellin concentration for 30 min before cultivation. Four levels of different P concentrations (7.75, 15.5, 31 and 62 mg/L) were prepared by monopotassium phosphate (KH2PO4) fertilizer and their effects were evaluated under different levels of gibberellin. Growth, flowering and physiological indicators were measured and evaluated during and at the end of the growing season. All data were statistically analyzed by analysis of variance (ANOVA) using the SAS 9.1 software (SAS Inc., Cary NC). Duncan’s multiple-range test was performed at p = 0.05 on each of the significant variables measured. Results and discussion: The results showed that nutrient solution consumption was more than 60% lower in plant nutrition according to plant demand and EC of the nutrient solution compared to the complete replacement method. The concentration of nitrogen, potassium, and calcium in Chinese lettuce decreased under the EC control method. Leaf magnesium concentration increased in all cultivars nourished according to EC control and plant nutrient demand compared to the complete nutrient replacement method. The highest concentrations of micronutrients such as iron, zinc, and manganese were observed in the complete nutrient replacement method in all three lettuce cultivars. The results also showed that the amount of Fe and Mn in the leaf of red lettuce cultivar and zinc concentration in the leaf of Chinese lettuce and Kazeroon decreased significantly under nutrient replacement according to the EC control and plant nutrient demand. Conclusions: Application of 31 mg L-1 of P and the impregnation of the bulb with the concentration of 200 mg L-1 of gibberellic acid is recommended to accelerate the harvest elongated branches, to enhance the number of branches and the vase life of polianthes flower under hydroponic cultivation. [ABSTRACT FROM AUTHOR]

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Apple is one of the most popular fruit worldwide with a continuous demand for higher quality apples, especially storable varieties. Nitrogen is one of the most important elements in apple growth and production. Additionally, different nitrogen forms can have different effects on plant growth and fruit qualities. In this research, we investigated the effect of five types of nutrient solutions with different amounts of ammonium nitrogen to total nitrogen on post-harvest physiology of apples for two seasons (2016-2017 and 2017-2018). Apple seedlings of three cultivars (Granny Smith, Gala and Golab Kohans) were grown on a soil-based substrate in a factorial experiment of randomized complete block design. After harvesting, the fruit were stored in 0 ○C and 90-95% humidity for 45 days for Golab, 90 days for Gala and 160 days for Granny Smith. Fruit traits were evaluated throughout storage period. The results showed that the increase in ammonium nitrate concentration significantly increased fruit weight, fruit dry weight, and titratable acidity. However, this increase in ammonium nitrate reduced firmness and the amount of total soluble solids with an increase in fruit weight loss index during storage. Furthermore, the results illustrated that the best fruit in terms of storability and postharvest performance were attributed to the nutrition solution without ammonium nitrate.

The objective of this study was to examine the integration of a wild leafy vegetable, Cichorium spinosum L., in vertical farms. This research comprises two experiments focusing on different "white" light products and nutrient solutions. During both experiments, the temperature varied between 25 and 28 °C, relative humidity ranged from 50 to 70 %, carbon dioxide was at 450 ppm, and light intensity was set at 300 μmol m -2  s -1 respectively. In the lighting experiment, the three spectra used had the commercial names Neutral, Full and a SunLike™, and their spectral composition (blue:green:red:far-red) were 14:32:43:10, 16:36:40:8, and 21:34:36:7 respectively. The photoperiod was set to 12 h and the plant density was 50 plants m -2 . Results showed no significant impact on agronomical parameters and leaf anatomy. The stomatal length and width decreased as the red:blue ratio of the light sources decreased, being greater in the Neutral treatment (red:blue ratio of 3.1) compared to the Full and SunLike™ (red:blue ratios of 2.5 and 1.7 respectively). Based on these results the preferable "white light" product was the one with the highest efficiency and lowest market price at the time of the experiment. In the nutrient solution experiment, the agronomical and nutritional attributes of stamnagathi plants supplied with a control nutrient solution, "N10-Fe15" were compared to plants cultivated under limited nitrogen, "N4-Fe15" and elevated iron, "N10-Fe48", EC was 1.5 ds m -1 , and pH was 5.6-6.5. The experiment simulated commercial practices by increasing the photoperiod to 15 h and plant density to 100 plants per square meter. The results did not demonstrate significant effect of the nutrient solution differences on the agronomical characteristics except from a decrease in total Kjeldahl nitrogen under limited nitrogen conditions. Notably, leaf tissue phosphorus content increased under elevated iron conditions. The nitrate content remained within safe for consumption thresholds for all treatments. Based on these results, stamnagathi can be integrated in vertical farms under limited nitrogen conditions. Stamnagathi's resilience to elevated iron in the nutrient solution demonstrated its potential for future biofortification experiments., Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Georgia Ntatsi, the coresponding author of this manuscipt, is Associate Editor for Heliyon Agriculture (a section of Heliyon). If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors. Published by Elsevier Ltd.)

Purpose: Nitrogen (N) / potassium (K) nutrient balance has been studied for some ornamental plants, however, available information is limited. Here we investigate the optimum N and K balance and concentration for lisianthus production in soilless medium. Materials and methods: The effect of three N / K balances: 1.43, 2.14 and 4.29, prepared by varying the concentration of N and K, were evaluated in lisianthus grown in soilless medium (volcanic rock). Results: Plants fertigated with a N / K balance of 2.14 exhibited enhanced height and stem dry weight when compared to plants fertigated with a balance of 4.29, and a higher flower buds count and total dry weight than those fertigated with a balance of 1.43 or 4.29. Plants fertigated with a balance of 2.14 exhibited increased dry weight when N was reduced from 15 to 9 meq L−1 and K from 7 to 4.2 meq L−1, suggesting that lisianthus does not require high levels of these nutrients. Although shoot N concentration was not correlated with N concentration in the nutrient solution or balance, increasing N in the shoot was associated with higher P and Mg in the plant tissues. In general, P, Ca, and Mg in plant tissues were unaffected by the external N / K balance, however, the internal P and Mg concentrations were positively correlated with shoot dry weight. Shoot K concentration significantly increased when the N / K balance decreased, which is related to the higher concentrations of external K when the balance decreased. Conclusions: The optimum N / K balance for lisianthus was 2.14. However, there was a concentration effect, as fertigation with solutions containing a N / K balance of 2.14 and an N and K concentration of 9 and 4.2 meq L−1 respectively, resulted in plants with the greatest dry weight.

Acclimatization is one of the key steps in the success of micropropagation of woody plants. Improvement of acclimatization of micropropagated woody fruit plants could be achieved in different ways. The purpose of this study was to optimize the acclimatization of micropropagated sweet cherry rootstock GiSelA 6 (Prunus cerasus 'Schattenmorelle' x Prunus canescens) through application of biostimulators of natural origin in floating system. A new generation of plant growth biostimulators Regoplant and Charkor (Agrobiotech, Ukraine) contain metabolism products of symbiotic fungus-endophyte of ginseng roots, cultivated in vitro. Micropropagated and rooted plantlets from cherry rootstock GiSelA 6 (Prunus cerasus 'Schattenmorelle' x Prunus canescens) were acclimatized in a floating system with 100 µl L-1 Regoplant or Charkor. As control plantlets with no additional treatments served. Multi-cell bedding plant trays filled with peat: perlite 1:1 (v:v) were used for acclimatization. Plants were grown in a greenhouse under high humidity conditions for one week and then humidity was gradually decreased. Data on some growth, physiological and biochemical parameters were collected 45 days after transplanting to ex vitro conditions. Regoplant (100 µl L-1) led the highest plants survival rate (86%), also the greatest values for the growth determined parameters. [ABSTRACT FROM AUTHOR]

In conditions of maintenance of environment parameters for plant growth, the use of nutrient solutions prepared with non-deficient fertilizers is an effective method of reducing the cost of vegetable production. The article examines economic prospects of the use of technologies of small-volume (0,15 — 0,3 l./per plant) the intensity of light-culture of plants in nutrient solutions, prepared on the basis of industrially produced fertilizers ‘Rastvorin A’, ‘Akvarin’, ‘Agricola’ and ‘Kemira Lux’, which are recommended for leafy crops. ‘Knop’ solution as one of the most effective for intensive technologies of the light-culture of leafy crops was used as a control. The object of study was a lettuce, cultivar ‘Tayphun’ and parsley cultivar ‘Bogatyr’. Plants were grown under different levels of light irradiance. Light during the growing period for both species was for 12 hours, the temperature was maintained at 20-22C° in the day and 18-20C° at night, air humidity between 60-65%. The duration of the vegetation period is 25 days. As a result of the study, it was shown that the productivity of lettuce cultivar ‘Typhun’ and parsley cultivar ‘Bogatyr’ that were grown on nutrient solutions ‘Agricola’ and ‘Rastvorin’ was very high. The content of nitrates for all cases was not extended more than the MCL. The highest productivity in the range of irradiance between 60 and 40 watts has been observed in lettuce plants of cultivar ‘Typhoon’, grown under light-culture system with the use of nutrient solutions ‘Akvarin’ and ‘Agricola’. Thus, the study carried out has showed that nutrient solutions ‘Akvarin’, ‘Agricola’ and ‘Rastvorin’ can be recommended for cultivation of leafy crops under condition of changeable light irradiation.

Purpose: Nitrogen (N) / potassium (K) nutrient balance has been studied for some ornamental plants, however, available information is limited. Here we investigate the optimum N and K balance and concentration for lisianthus production in soilless medium. Materials and methods: The effect of three N / K balances: 1.43, 2.14 and 4.29, prepared by varying the concentration of N and K, were evaluated in lisianthus grown in soilless medium (volcanic rock). Results: Plants fertigated with a N / K balance of 2.14 exhibited enhanced height and stem dry weight when compared to plants fertigated with a balance of 4.29, and a higher flower buds count and total dry weight than those fertigated with a balance of 1.43 or 4.29. Plants fertigated with a balance of 2.14 exhibited increased dry weight when N was reduced from 15 to 9 meq L−1 and K from 7 to 4.2 meq L−1, suggesting that lisianthus does not require high levels of these nutrients. Although shoot N concentration was not correlated with N concentration in the nutrient solution or balance, increasing N in the shoot was associated with higher P and Mg in the plant tissues. In general, P, Ca, and Mg in plant tissues were unaffected by the external N / K balance, however, the internal P and Mg concentrations were positively correlated with shoot dry weight. Shoot K concentration significantly increased when the N / K balance decreased, which is related to the higher concentrations of external K when the balance decreased. Conclusions: The optimum N / K balance for lisianthus was 2.14. However, there was a concentration effect, as fertigation with solutions containing a N / K balance of 2.14 and an N and K concentration of 9 and 4.2 meq L−1 respectively, resulted in plants with the greatest dry weight. [ABSTRACT FROM AUTHOR]

Neste trabalho, objetivou-se avaliar os efeitos de omissões de nutrientes na produção de matéria seca e nos parâmetros de crescimento do bastão-do-imperador. O trabalho foi realizado em casa de vegetação da área experimental do Departamento de Ciência do Solo da Universidade Federal de Lavras (Lavras, MG), no período de janeiro de 2007 a janeiro de 2008. O delineamento experimental foi inteiramente casualizados com quatro repetições e oito tratamentos: Solução Hoagland & Arnon completa, soluções nutritivas com as omissões de N, de P, de K, de Ca, de Mg, de S e de B. Foram avaliadas a altura das plantas, diâmetro das hastes, número de hastes, número de folhas por hastes e volume da raiz. Posteriormente, as plantas foram divididas em folhas, hastes, rizoma e raiz para determinação da massa de matéria seca de cada parte. A omissão de nutrientes afetou os parâmetros de crescimento das plantas e a produção de matéria seca. Observou-se que o bastão-do-imperador mostrou-se mais exigente em B, K, N, P e S na fase inicial de crescimento do que em Ca e Mg. A redução da matéria seca total das plantas foi influenciada na seguinte ordem: B > K > N > P > S > Mg > Ca.The objective of this work was to evaluate the effect of simple and multiple nutrient omissions on the dry matter production and growth parameters of torch ginger plants. The experiment was carried out under greenhouse conditions at the Soil Science Department of Federal University of Lavras (Lavras-MG). The experiment was started in January 2007 and lasted for 12 months, following a completely randomized design, with four replicates and eight treatments: Complete Hoagland & Arnon nutrient solution, and nutrient solutions without N, P, K, Ca, Mg, S, and B. Plant height, stem diameter, number of stems, number of leaves per stem, and volume of root were evaluated. Subsequently the plants were divided into leaf + pseudostem, rhizome, root and tillers for dry matter determination. The nutrient omissions affected the growth parameters and dry matter production. It was observed that torch ginger is more demanding in B, K, N, P and S at the initial phase of growth rather than in Ca and Mg. The reduction of the total dry matter weight of the plants was affected in the following order: B> K> N> P> S> Mg> Ca.

Environmental pollution has a harmful action on bioresources, including agricultural crops. It is generated through many industrial activities such as mining, coal burning, chemical technology, cement production, pulp and paper industry, etc. The toxicity of different industrial wastes and heavy metals excess was evaluated using crop plant assays (germination and hydroponics seedlings growth tests). Experimental data regarding the germination process of wheat (from two cultivars) and rye seeds in the presence of industrial wastes (thermal power station ash, effluents from a pre-bleaching stage performed on a Kraft cellulose – chlorinated lignin products or chlorolignin), along with use of an excess of some heavy metals (Zn and Cu) are presented here. Relative seed germination, relative root elongation, and germination index (a factor of relative seed germination and relative root elongation) were determined. Relative root elongation and germination index were more sensitive indicators of toxicity than seed germination. The toxic effects were also evaluated in hydroponics experiments, the sensitivity of three crop plant species, namely Triticum aestivum L. (wheat), Secale cereale (rye), and Zea mays (corn) being compared. Physiological aspects, evidenced both by visual observation and biometric measurements (mean root, aerial part and plant length), as well as the cellulose and lignin content were examined.

Objetivou-se, neste trabalho, estudar os efeitos de diferentes soluções nutritivas aplicadas em duas vazões na produção hidropônica da alface (Lactuca sativa), cultivada pelo sistema NFT (Nutritive Film Technique). O experimento foi conduzido em casa de vegetação, na unidade de pesquisa em agricultura irrigada da Universidade Estadual de Maringá. Os tratamentos constaram de três soluções nutritivas com concentrações diferentes (S1=0,8 dS/m, S2=1,2 dS/m e S3=2,5 dS/m), combinadas com duas vazões de aplicação (V1=0,8 L.min-1 e V2=1,2 L.min-1 ) nos canais de cultivo em esquema fatorial 3 x 2. Para avaliar o efeito dos tratamentos no desenvolvimento da cultura os dados foram submetidos à análise de variância (teste F), e os resultados avaliados através de teste de média de Tukey (5%). A análise dos resultados permitiu concluir que os fatores solução e vazão não apresentaram interação significativa e que os maiores valores avaliados de biomassa fresca e diâmetro do caule foram obtidos no tratamento solução 2 (CE= 1,2 dS/m).The porpose of this work was to study the effect of different nutrient solutions applied in two outflow in the hidroponic yeld of lettuce (Lactuca sativa). This research was accomplished at greenhouse through hydroponic system NFT in Maringá State University. The treatments consisted of three nutrient solutions (S1=0,8 dS/m, S2=1,2 dS/m e S3=2,5 dS/m) combined with two flows of application (V1=0,8 L.min-1 e V2=1,2 L.min-1 ) in the growing channels of cultivation. The flows of application of the solutions were 0,8 L.min-1 (V1) and 1,2 L.min-1 (V2), placed alternately in the growing channels in a 3 x 2 factorial scheme. To evaluate the effect of treatments on the culture development the data were submitted to the variance analysis (Test F), and the results were evaluated through Tukey (5%) average test. The analysis of the results allowed to conclude that the factories nutrient solution and flow did not show significant interaction. The greater values evaluated of biomass fresh and diameter of stem by plant were obtained in treatment solution 2 (EC= 1,2 dS/m).

Irrigation water of poor quality that is high in salts, alkalinity-inducing compounds, and boron (B) threatens global agricultural production. The objective of the present study was to determine whether supplementary calcium (Ca) and potassium (K) ameliorate the response of tomato plants to a simultaneous combination of these stress conditions. Irrigation water high in alkalinity, salinity, and B reduced plant growth, which was associated with a partial impairment in the antioxidant system (reduction in catalase activity), impairment in water relations (reduced relative water content), decreased nutrient acquisition [lower nitrogen (N), phosphorus (P), K, Ca, and magnesium (Mg) content]; and specific toxicity due to the increase in shoot sodium (Na) and B. However, stressed plants exhibited partially improved growth when supplemented with greater concentrations of Ca and K, which were associated with enhanced P concentration, maintenance of chlorophyll a concentration, and/or partially restored N, P, K, Ca, and Mg uptake. [ABSTRACT FROM PUBLISHER]

Os objetivos deste trabalho foram caracterizar os sintomas visuais de deficiência de micronutrientes e avaliar efeitos desses micronutrientes no estado nutricional da mamoeira. O experimento foi realizado em casa de vegetação utilizando-se solução nutritiva, de fevereiro a junho de 2003. Foram utilizadas plantas de mamoneira (Ricinus communis L.) do híbrido comercial Íris. Os tratamentos foram: completo, omissão de B, omissão de Cu, omissão de Fe, omissão de Mn, omissão de Mo e omissão de Zn. A omissão de B, Fe e Mn resultou em sintomas característicos de deficiência. Os sintomas se desenvolveram primeiramente em plantas deficientes em Fe ou Mn, seguidas das deficientes em boro. A produção de matéria seca foi afetada na seguinte ordem: Fe>Mn>B. Tanto as folhas superiores como as inferiores refletem o estado nutricional da mamoneira em relação a B, Cu, Fe, Mn, Mo e Zn. O teor de clorofila nas folhas, medido em unidades SPAD, foi influenciado pela omissão dos micronutrientes.The objectives of this work were to characterize the visual symptoms of micronutrient deficiencies, and their effects on nutricional status of castor beans. A greenhouse experiment with nutrient solutions was carried out from February to June, 2003. The commercial hybrid "Iris" was used. Treatments were as follows: complete, minus B, minus Cu, minus Fe, minus Mn, minus Mo, and minus Zn. Symptoms of deficiency were observed in the treatments with omission of B, Fe, and Mn. The symptoms firstly developed when either Fe or Mn was deficient, and they were followed by those deficient in boron. Dry matter yield was affected in the decreasing order: Fe>Mn>B. Both upper and lower leaves reflect the nutritional status of the castor bean with respect to B, Cu, Fe, Mn, Mo and Zn. Leaf chlorophyll, as measured in units SPAD, was influenced by the treatments.

Dois experimentos em casa de vegetação foram conduzidos visando identificar parâmetros morfológicos ligados à tolerância ao alumínio (Al) e estabelecer a concentração de Al e o tempo de cultivo suficientes para a expressão da tolerância ao Al, em duas cultivares de arroz, em solução nutritiva. Plantas de determinado comprimento radicular máximo foram transferidas para solução nutritiva com quatro concentrações de Al (0, 80, 160 e 320 mimol L-¹), a pH 4,0. Em cada coleta, foram medidos o comprimento máximo radicular, área radicular, área foliar e massa seca de raízes e parte aérea. Apenas os parâmetros morfológicos ligados ao sistema radicular possibilitaram o reconhecimento da tolerância diferencial das cultivares; a elongação radicular relativa foi a medida mais sensível. Quatro dias de exposição ao Al foram suficientes para a detecção da tolerância diferencial por meio da elongação radicular relativa. Os procedimentos estabelecidos nos experimentos podem ser utilizados para a avaliação de um número maior de cultivares.Two nutrient solution greenhouse experiments were conducted to identify morphological parameters that express Al tolerance and to determine the influence of period of plant growth and Al concentration necessary for tolerance discrimination, in two rice cultivars. Plants of known maximum root length were transferred to nutrient solution at four levels of Al (0, 80, 160 and 320 mumol L-1) with a pH 4.0. In each collection, the new maximum root length was measured in addition to root and leaf areas, and root and shoot dry weights. Only the morphological parameters related to the root system differentiated Al tolerance of the cultivars, and relative root elongation was the most sensitive. Four days of exposure to Al were sufficient to detect differences in Al tolerance by means of relative root elongation. The methods established in this study can be useful in evaluating larger number of cultivars.

Potato minituber production through hydropony: assessment of a system combining the NFT and Gravel Culture techniques for two types of nutrient solutions. The potato minituber production is the classical intermediate stage enabling field use of potato materials with an in vitro origin. This production of minitubers may be achieved through various techniques. Most often however they are based upon bedding vitroplantlets or vitroplantlets cuttings in an organic substratum which is disinfected or not. The soilless culture of plants stemming from vitrotubers to produce minitubers with a superior health quality was tested within a hydroponic system. Two types of nutrient solutions were compared: a nitrogen rich one (NPK, mg/l, 180-40-300) and a phosphorus rich one (NPK, mg/l, 60-150-300). In order to initiate the cultures, presprouting microtubers of several varieties (Bintje, Kennebec, Spunta, Saturna, Desiree and Gasore) were used. Multiplication rates ranged between 13.2 (Saturna) and 3.8 (Kennebec) minitubers with a grade higher than 10 mm (more than 1.5 g). As the selected density of the plants was 59 plants per square metre, the yield per square metre varied from 224 to 779 minitubers with a grade higher than 10 mm. The obtained number of minitubers depended especially on the variety. The phosphorus enrichment of the nutrient solution induced an increased number of minitubers produced with a grade higher than 15 mm (more than 5 g). The health state of the produced tubers was excellent.

Application of nutrient solutions in fertigation could change chemical properties of soil. Nutrient solutions for highbush blueberry are specific because of characteristic relations among nutrients and acid reaction. Investigations were conducted in the years 2002–2004 on a 10-year old plantation of highbush blueberry cv. ‘Bluecrop’. There were searched effects of fertigation using 3 nutrient solutions (F-1, F-2, F-3) contained increased levels of N-NH, N-NO3, P, K, Mg and constant B and Mo (Ca, S-SO4, Fe, Mn, Zn, Cu from water) on the contents of nutrients, sodium and aluminium in soil. Fertigation of nutrient solutions F-1, F-2, F-3, in relation to drip irrigation F-0, resulted in the increasing contents of K, Mg, Fe, Mn, Zn and Cu in the plough layer (0–20 cm), while the nutrient solutions F-2 and F-3 upraised the contents of P, S-SO4 and B. The effect of fertigation on the increase of nutrient contents in the subplough layer (20–40 cm) was pointed out mainly for K and Mg. As a result of fertigation with the highest nutrient contents (F-3) the contents of N-NO3 increased in the subplough layer. In both layers a tendency to increase of N-NO3 was noted. Fertigation with nutrient solution F-3 reduced the content of chlorides, while F-2 and F-3 sodium in the plough layer. As a consequence of fertigation with nutrient solutions F-2 and F-3 having pH 5.50 the lowering of soil pH in the plough layer (0–20 cm) was indicated in comparison to drip irrigation (pH of water 7.37). No effect of fertigation was found in the pH of the subplough layer (20–40 cm). As a result of a reduced soil pH the content of aluminium in the plough layer increased. Fertigation with nutrient solutions F-1 to F-3, in relation to drip irrigation F-0, resulted in an increased of EC of the plough and partly in the subplough layer.

Fertigation with the nutrient solutions containing macro and microelements could influence on the nutrient status of highbush blueberry. Studies were conducted in the years 2002–2004 on a 10-year old plantation of highbush blueberry cv. ‘Bluecrop’. The aim was to analyze the effect of fertigation using 3 nutrient solutions (F-1, F-2, F-3) in comparison to drip irrigation (F-0) on the contents of macro- and microelements as well as sodium and aluminium in leaves. Fertigation with nutrient solutions F-1, F-2 and F-3 in relation to drip irrigation (F-0) increased the contents of nitrogen, potassium and calcium in the leaves of highbush blueberry cv. ‘Bluecrop’ at both terms of leaves collection (15.06 and 15.07) while it reduced the content of magnesium with the application of nutrient solutions F-2 and F-3 at the second term of study. No distinct effect of fertigation on the contents of phosphorus and sulphur in leaves was found. Among microelements the greatest effect of fertigation was indicated for boron. Nutrient solutions F-2 and F-3 at the first term as well as F-1, F-2 and F-3 at the second one increased boron content in leaves. Fertigation was found to have an effect on the increase of manganese and copper contents at the term II and zinc at the term I. No variation was recorded in iron content in leaves under the influence of fertigation. Fertigation reduced the content of aluminium in leaves of highbush blueberry. The effect was shown mainly under the influence of the application of nutrient solution F-2. Contents of N, P, K, Zn, Na and B decreased but Ca, Mg, Fe, Mn and Al increased in leaves between the first (15.06) and second II (15.07) term of study. No changes were found in contents of S or Cu in leaves of highbush blueberry at both sampling terms. For the evaluation of highbush blueberry nutrition status in Poland the term II seems to be more advantageous. It is the second half of July, after the first harvest of cv. „Bluecrop”. In this period there is the stabilization of vegetative growth with marked effects of bushes yielding.

Fertigation in conjunction with traditional spread fertilization could improve the growth and yield of highbush blueberry. Study was conducted in the years 2002–2004 on a 10-year old plantation of highbush blueberry cv. ‘Bluecrop’. The effect of fertigation with 3 nutrient solutions (F-1, F-2, F-3) was investigated in comparison to drip irrigation (F-0) on growth and yield of highbush blueberry. Fertigation with nutrient solution F-1 containing (in mg·dm-3): 100 (N-NH4+N-NO3), 30 P-PO4, 60 K, 30 Mg, 0.30 B and 0.03 Mo, and from the water contents of 84.5 Ca, 47.9 S-SO4, 4.8 Na, 6.6 Cl, 0.160 Fe, 0.054 Mn, 0.041 Zn and 0.009 Cu (pH 5.50, EC 1.10 mS·cm-1) had a positive effect (in comparison to the drip irrigation) on the fruit yield and single fruit mass of highbush blueberry cv. ‘Bluecrop’. An increase of nutrient contents in nutrient solution F-2 to the level of (in mg·dm-3): 150 (N-NH4+N-NO3), 45 P-PO4, 90 K, 45 Mg, 0.30 B and 0.03 Mo (the others as in F-1; pH 5.50 and EC 1.45 mS·cm-1) did not reduce the yield in relation to F-1, while it lowered the mass of one fruit. Yields of highbush blueberry under the influence of drip fertigation in relation to drip irrigation (F-0), at the optimal soil fertility obtained on the basis of spread fertilization, increased as follows: F-1 at 17.3%, F-2 at 21.9% and F-3 at 5.3%. The greatest effect of fertigation on yield of highbush blueberry was found in the year of soil drought, in which the highest rates of nutrient solutions F-1 and F-2 were applied. Fertigation with the nutrient solutions F-1 to F-3 increased dry matter contents of fruits, however it was lower than in drip irrigation. No nitrates or nitrites were detected in fruits of highbush blueberry. Highbush blueberry cv. ‘Bluecrop’ is a plant with high nutrient requirement. Average yearly nutrient rates for 10–13 years old plantation applied with the treatments F-1 and F-2 (sum of spread fertilization and fertigation) were: 19–24 g N, 10–12 g P, 7–10 g K, 9 g Ca, 6–8 g Mg and 4 g S·m-2·bush-1. For horticultural practice the nutrient solution F-1 could be recommended because of its advantageous effect on yield and the lowest fertilizer expenditure.

Objective Hydroponics Cymbidium sinensis on rooting was studied to select suitable concentration of auxin and solutions formula so as to provide basis for virus-free propagation. [Method] Cymbidium sinensis plantlets with 20.0-30.0 cm height were chosen to induce aquatic root system with different concentrations of 2-lndole-3-Hu-tytric acid (IBA),1- indoleacetie acid (IAA ), 3-naphthlcetic acid (NAA) treatments, then cultured in different nutrient solutions, and the comparative analysis of the different rootage and culture was launched on the basis of growth. [Result]The results showed that in the same condition the most suitable I HA was the IHA with the concentration of 5.0 mg/L, and 6 hours for processing, by which 30 percent plantlets could push out new roots with average length of 15.3 mm after 28 d growth, while the most proper IAA was the IAA with the concentration of 5.0 mg/l, and 2 hours for processing, by which 20 percent plantlets could pushes out new roots with average length of 7.5 mm after 28 d growth, and the relevant data of NAA was 5.0 mg/L,2 hours,20 percent, and the average length was 2.5 mm. 1/ 2HAmon produced better growth-promotion effects than Yamazaki +Hoagland. [Conclusion]The best auxin was IHA with the concentration of 5.0 mg/l, and 6 hours for processing. 1/2 Hoagland and Arnon formula could lead to better growth. [ABSTRACT FROM AUTHOR]

We examined the reaction of vine rootstocks based on hybrids of Vitis riparia, Vitis rupestris and Vitis berlandieri, to deficiency and excess of Ca and Mg in nutrient solutions in hydroponics cultivation in order to investigate their resistance to different levels of the two elements in calcareous and acid soils. It was found that the investigated rootstocks respond to imbalance of Ca and Mg. The reaction occurs on the biometric characteristics of plants - height, weight, dry matter content and on the composition -- content of Ca, Mg, Fe and Mn in plants. We tested hybridized rootstocks SO4 (Berlandieri X Riparia selection Oppenheim 4), Fercal, (Riparia X Rupestris) Couderc 3.309 and Gravesac, which are widely used in practice. Relatively less development and lower sensitivity to the studied conditions was established for rootstocks Couderc 3,309 and Gravesac. They also react with slight change of their chemical composition under conditions of deficiency and excess of Ca and Mg. It was established that, high levels of calcium in plant biomass inhibit absorption of magnesium, and the dependence is particularly pronounced for rootstock Fercal. For rootstocks SO4 and Fercal well expressed influence of medium unbalanced with calcium on the content of iron and manganese in plants was observed. [ABSTRACT FROM AUTHOR]

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Nutrient solution composition plays an important role in root uptake rate due to interactions among nutrients and internal regulation. Studies to determine the optimum nutrient solution concentration are focused on individual ions, ignoring the adaptation mechanisms triggered by plants when growing in a varying external nutrient concentration. The objective of the present study was to determine the response in growth and tissue ion concentration of lilium cv. 'Navona' to nutrient mixtures of varying proportions of nitrogen (N), potassium (K+), and calcium (Ca2+) in solution using mixture experiments methodology in order to determine the optimum concentration. Bulbs of lilium were transplanted in plastic crates and drip-irrigated with the treatment solutions, which consisted of a mixture of N, K+, and Ca2+ whose total concentration was 340 mg L-1 and minimum concentrations of each ion was 34 mg L-1. Chlorophyll concentration (SPAD), shoot fresh weight (FW), leaf FW, and leaf area were measured 60 days after transplanting and ion analysis was performed on shoot tissues from selected treatments. Lilium exhibited a moderate demand for N and K+ (136-170 mg L-1 N and 116-136 mg L-1 K+) and a very low demand for Ca2+ (34-88 mg · L-1). This low demand may be due to the remobilization of the nutrients stored in the bulbs. Integrating the predictions of the models estimated to produce >90% of maximum growth, the optimum nutrient solution should contain Ca2+ at a concentration between 34 and 126 mg · L-1, K+ between 119 and 211 mg · L-1, and N between 92 mg · L-1 and 211 mg · L-1. Increasing external N concentration affected internal N concentration but not internal K+ or Ca2+ concentrations, despite that the increase in external N was associated with a decrease in external K+ and Ca2+. Similar trends were observed for external K+ and Ca2+ concentration. In conclusion, lilium was able to maintain a relatively constant K+ and Ca2+ concentration regardless of the lower concentration in the nutrient solution when N was increased (similar response was observed for K+ and Ca2+) and it has a low Ca2+ demand and moderate N and K+ supply. [ABSTRACT FROM AUTHOR]

Copyright of Revista Chapingo Serie Horticultura is the property of Universidad Autonoma Chapingo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The present study was carried out at Liliana Dimitrova Horticultural Research Institute, with the objective of evaluating the effect of nutrient solutions with different nitrogen/potassium fertigation ratios for protected tomato (HA-3019 hybrid) crop on biomass accumulation and macronutrient uptake within two planting times. Four N/K ratios (1:1.5; 1:2.0, 1:2.5 or production check, and 1:3.0) were studied in spring-summer season (March/July) and winter (September/January). Biomass accumulation (g.m-2) and N, P, K, Ca and Mg consumption were determined per plant organ and total biomass (g.m-2) for each treatment. In winter, dry weight and N, K and Ca uptake were significantly higher than in spring-summer season, whereas the top growing and nutrient consumption period corresponded to full production phase. The lowest leaf, stem and total biomass production corresponded to N/K ratio 1:1.5 in spring-summer; meanwhile dry fruit weight was significantly higher for N/K ratios 1:2.0 and 1:2.5. In winter season, significant fruit and total biomass values were recorded for N/K ratio 1:2.5 (production check); however, leave growth was similar in treatments 2, 3 and 4 (1:2.0, 1:2.5 and 1:3.0). Macronutrient extraction showed a similar behaviour to that obtained for biomass accumulation. [ABSTRACT FROM AUTHOR]

Abstract: The effect of 50% shading and NO3:NH4 ratio (0:100, 75:25, 50:50, and 25:75) in the nutrient solution on growth, yield, quality and N metabolism in hydroponically grown strawberry (Fragaria × ananassa var Camarosa) was evaluated. Both fresh and dry weights of leaves were significantly lower when a high concentration of either NO3 (100%) or NH4 (75%) was the sole N source in the nutrient solution. In unshaded plants, increasing of both NH4 and NO3 ratio in the nutrient solution reduced photosynthetic (Pn) rate, however in shaded plants the reduction of Pn became more pronounced at a higher ratio of NH4 in the nutrient solution. The yield in terms of fresh and dry weight of fruit per plant was significantly increased at the 75:25 and 50:50 (NO3:NH4) treatments. Fruit size was significantly affected by the treatments, so that the biggest fruits in both shaded and unshaded plants were obtained under the 75:25 and 50:50 (NO3:NH4) treatments. Total soluble solid (TSS) in unshaded plants was increased with increasing NH4 ratio in the nutrient solution, however in shaded plants it was reduced at high NH4 ratio in the nutrient solution. In both shaded and unshaded plants, higher concentration of NH4 significantly reduced the post-harvest life of the fruits. The increase of tissue N concentration was nearly proportional to the NH4 concentration in the nutrient solution. The activity of nitrate reductase (NR) was increased by increasing NH4 from 0 to 50% and then reduced at a higher ratio of NH4 in the solution. Shading increased NH4 concentration so that the shaded plant had nearly twice as high NH4 concentration in the leaves. The increase of NH4 concentration induced by shading could be partially the reduction of NH4 assimilate because of the shortage of carbohydrate. [Copyright &y& Elsevier]

Synthetic chelators are commonly used in hydroponic media to solubilize iron (Fe); however, the fate of these chelators is unknown. This study examined the persistence of three synthetic chelators, ethylenediaminetetraacetate (EDTA), diethylenetriaminepentaacetate (DTPA), and ethylenediaminedisuccinate (EDDS) in a bench-scale lettuce production system. The EDDS concentration decreased rapidly within 7d, most likely due to biodegradation. The EDTA and DTPA concentrations stayed steady throughout the experiments despite additions to maintain a constant volume and loss of chelator may have been due to either plant uptake or photodegradation of the chelator. Despite large differences in solution chemistry, the final shoot concentrations of iron (Fe), manganese (Mn), copper (Cu), and zinc (Zn) were similar among chelator treatments, whereas root concentrations of these same elements were highly variable. The concentration of DTPA in a commercial lettuce production system was measured and highly variable concentrations were found. [ABSTRACT FROM AUTHOR]

Kiwifruit plants were grown in sand/perlite mixtures and irrigated with nutrient solutions containing 0.025, 0.2, and 0.5 mM boron (B) combined with 0, 1.5, 3, and 6 mM triisopropanolamine (TIPA). Growth parameters and B concentration of various plant parts were investigated. By increasing TIPA concentration from 1.5 to 6 mM in solutions containing 0.2 mM B, the concentration of leaf B decreased. However, even the highest TIPA concentration did not decrease B concentration of leaves when its concentration in solution was 0.5 mM. The accumulation of B in leaves and its relatively low concentration in roots and shoots indicates that kiwifruit lacks a B exclusion mechanism. Furthermore, the occurrence of higher B concentrations in mature leaves in comparison to younger ones is evidence of phloem B immobility of kiwifruit plants. In another experiment, the nutrient solutions contained three B levels (0.025, 0.1, 0.2 mM) and plants sprayed with the antitranspirant compound “vapor gard” with aqueous solutions containing 5, 10, and 15% “vapor gard.” Moderate B toxicity symptoms were exhibited by plants irrigated with solutions containing 0.1 mM B. However, when plants sprayed with the antitranspirant compound no visual symptoms of B toxicity were exhibited. Severe B toxicity symptoms were exhibited by plants irrigated with solutions containing 0.2 mM B even when they were sprayed with “vapor gard.” As the concentration of “vapor gard” increased from 5 to 15%, the shoot height of plants, the mean shoot fresh weight and the mean leaf fresh weight decreased for all B treatments. When plants irrigated with solutions containing 0.1 and 0.2 mM B, the spray with “vapor gard” (10 and 15%) resulted in a decrease of B concentration of leaves. [ABSTRACT FROM AUTHOR]

Chelator-buffered hydroponic solutions provide low and buffered free-metal concentrations and allow the easy calculation of nutrient species expected in these solutions. Some researchers suspect that the solutions allow plant uptake of chelates and that this uptake explains the failure of the free-ion activity model using these solutions. To determine the amount and method of chelate uptake, swiss chard was grown in solution culture in growth chambers for about three wks and then transferred to solutions containing 14C-EDTA, 14C-citrate, or 14C-L-histidine for a 21-hour assay. Much higher root and shoot 14C were found from treatments containing metabolites histidine (2706 097 shoot Bq 14C) or citrate (2241 953 shoot Bq 14C) than EDTA (280 110 shoot Bq 14C). Passive transpirational flow could explain all of the EDTA uptake, but active uptake would be required to explain most of the citrate and histidine uptake even assuming some adsorption of ligand bound to roots. Swiss chard grown in solutions with the same total EDTA concentrations, but different amounts of Fe bound to EDTA, had ≥3-fold differences in root and shoot 14C concentrations. In a second experiment, swiss chard roots removed more EDTA from solutions containing mostly M-EDTA0 than M-EDTA1- or M-EDTA2- (288 140, 245 051, and 192 559 Bq 14C, respectively) suggesting plant selectivity for EDTA and a non-apoplastic route of uptake or an effect resulting from root cell-wall adsorption. Results indicated buffering of metals by ligands allowed some ligand uptake with much more uptake occurring with metabolites citrate and histidine than EDTA. A passive or indiscriminate form of uptake does not appear to explain all EDTA uptake with a selectivity by swiss chard for M-EDTA complexes of lower charge. [ABSTRACT FROM AUTHOR]