Concentration In Nutrient Solution Research Articles

PRODUÇÃO E QUALIDADE DE FRUTOS DE PEPINEIRO EM DIFERENTES CONCENTRAÇÕES DE SOLUÇÃO NUTRITIVA

Cucumber is a vegetable crop widely consumed fresh and appreciated by a source of vitamins and minerals. It is a crop suitable for cultivation in protected environment, but little research has been carried out to improve the cultivation of this species under such conditions. Our aim was to evaluate the effects of different concentrations of nutrient solution on yield and fruit production and quality of cucumber grown in coconut fiber substrate. The experiment was conducted in greenhouse utilizing design in randomized block, with four replications and five plants per plot, were evaluated five concentrations of nutrient solution (12.5; 17; 25; 50 and 100% that after dilution resulted in electrical conductivities of 1.0, 1.2, 1.5, 2.3 and 3.8 dS m -1 , respectively). At 84 days after transplanting fruits of cucumber were harvested to evaluate yield and fruit quality. The reduction of nutrient concentration in the standard nutrient solution from 100% to 12.5% did not affect cucumber production. Biometric characteristics mean weight, longitudinal diameter, fruit storage thickness and titratable acidity are reduced as a function of the electrical conductivity of the nutrient solution from 1.0 to 3.8 dS m -1 . The concentration of nutrients in the solution was 67.5% of the standard nutrient solution, corresponding to 111.58 g of N-KNO 3 , 50.00 g of P-MAP, 62.44 g of K-KCl, 241.50 g of Ca-CaNO 3 and 120.00 g of Mg-MgSO 4 , provide satisfactory yield and better physical-chemical quality of cucumber fruits.

Application effects of biogas slurry partly substituting for chemical fertilizer on autumn tomato production in winter-solar greenhouse

To explore the effects of biogas slurry coordinating chemical fertilizer on growth promotion of tomato, we used three kinds of typical biogas slurry as concentrated nutrient solution, respectively fermented from raw duck manure, pig manure, cow dung, while urea, monocalcium phosphate and potassium sulphate as auxiliary nutrition to balance the nutrient difference between different dilution ratios of biogas slurry. The results showed the biogas slurry partially substituting chemical fertilizer could significantly improve soil fertility, including available nitrogen, phospho-rus, and potassium. As for water soluble calcium, magnesium, iron, manganese and zinc in soil, biogas slurry application could activate their availability, with the magnitude of such effects depended on the fermentation level of raw materials and dilution ratio. Compared with chemical fertilizer, coordinating biogas liquid fertilizer significantly promoted the growth of tomato, with the yield increased by 55.9%-232.8% and the chemical fertilizer dosage decreased by 18.2%-85.0%. Furthermore, such effects became more prominent along with prolonged time. The fruit quality was significantly improved with the increases of lycopene, ascorbic acid and total sugar, and the decreases of acidity and nitrite concentration, and the decrease of NO2- by 35.6%-90.3%. In addition, the taste flavor of fruits was 7.0%-20.3% higher than that of chemical fertilizer treatment. The yield and quality of tomato took on nonlinear synchronization, and the relation between taste flavor and sugar/acid showed significantly positive correlation, which was affected by fertilizer type. Biogas slurry partly substituting chemical fertilizer could achieve the goals of high yield, high quality, environmental protection, efficient utilization of agricultural resources in tomato production.

Producción de biomasa, requerimiento nutrimental de nitrógeno, fósforo y potasio, y concentración de la solución nutritiva en orégano

The concentration of nutrient solution (NS) in soilless culture systems influences the accumulation of aerial biomass and nutrient contents. This research aimed to determine the optimal Steiner NS concentration for biomass production in Greek oregano (Origanum vulgare L. ssp. hirtum [Link] Ietswaart), and to quantify its nutritional requirement of nitrogen, phosphorus and potassium. A completely randomized design was established with five treatments and five replicates. The treatments were different NS concentrations: 25, 50, 75, 100 and 125 %. The experimental unit consisted of five bags (20 x 20 cm) with substrate (tezontle: 3 to 10 mm in diameter), with one plant each. The fresh and dry aerial matter and the concentration of N, P and K in the different samples were determined. The results showed significant statistical difference in the five variables. The highest fresh and dry matter production was obtained with the 50 and 75 % NS concentrations. While the lower concentrations did not meet the crop’s nutrient demand, the higher concentrations significantly decreased biomass production. The 50 % NS can be used in commercial hydroponic oregano production. The nutritional requirement of this crop is: 4.76 kg of N, 0.70 kg of P and 5.10 kg of K, per ton of fresh matter.

Economic and Financial Analysis of Tree Seedling Production Using Composted Biosolids Substrate

ABSTRACT The aim of this study was to evaluate production profitability of Croton urucurana and Cytharexyllum myrianthum seedlings produced in substrates composed of mixtures of composted biosolids and carbonized rice husk in different concentrations of nutrient solution. Seedlings were subjected to three doses of fertigation solutions. In order to check quality standards which indicated production cycle, the height, stem diameter and root quality were evaluated. Economic viability was determined by indicators of economic attractiveness commonly used for investment projects. Production costs of seedlings varied according to the production cycle, substrate compositions and nutritional management. The substrate with higher volume of composted biosolids and lower concentrated fertilizer was the one with the highest profitability and the lowest production cost.

Flavonoid Productivity Optimized for Green and Red Forms of Perilla frutescens via Environmental Control Technologies in Plant Factory

Perilla frutescens (Lamiaceae) is a dietary staple in Asia. It is an abundant source of flavonoids that are bioactively beneficial to human health and fitness. The current popularity of plant-based consumption is being driven by the healthful benefits of bioactive nutrition, and the concentration of bioactive agents found in raw plant materials is an important factor in the assessment of food quality. To test the feasibility of promoting flavonoid productivity in perilla plants via environmental treatment, plant factory technology was applied to perilla plant cultivation. Apigenin (AG) and luteolin (LT) are two of the most potent anticarcinogenic flavonoids in perilla, and these are also found in many vegetables and fruits. Quantitative analysis of AG and LT was conducted on plants cultivated under nine environmental forms of treatment imposed by three levels of light intensity (100, 200, and 300 µmol·m−2·s−1) combined with three levels of nutrient-solution concentration (1.0, 2.0, and 3.0 dS·m−1) for hydroculture. The contents of AG in green and red perilla plant were increased by high nutrient-solution levels under the same light intensity. In green perilla, the highest concentration of AG (8.50 µg·g−1) was obtained under treatment of the highest level of nutrient-solution (3.0 dS·m−1) and 200 µmol·m−2·s−1 of light intensity, whereas in red perilla, the highest concentration of AG (6.38 µg·g−1) was achieved from the highest levels of both of these forms of treatment (300 µmol·m−2·s−1 and 3.0 dS·m−1). The increase in AG content per plant between the lowest and the highest levels was recorded by 6.4-fold and 8.6-fold in green and red perilla, respectively. The behavior of LT concentration differed between green and red forms of perilla. LT concentration in red perilla was enhanced under nutrient deficiency (1.0 dS·m−1) and affected by light intensity. Different responses were observed in the accumulations of AG and LT in red and green perilla during treatments, and this phenomenon was discussed in terms of biosynthetic pathways that involve the expressions of phenylpropanoids and anthocyanins. The total yield of flavonoids (AG and LT) was improved with the optimization of those forms of treatment, with the best total yields: 33.9 mg·plant−1 in green Perilla; 10.0 mg·plant−1 in red perilla, and a 4.9-fold and a 5.4-fold increase was recorded in green and red perilla, respectively. This study revealed that flavone biosynthesis and accumulation in perilla plants could be optimized via environmental control technologies, and this approach could be applicable to leafy vegetables with bioactive nutrition to produce a stable industrial supply of high flavonoid content.

Optimasi Konsentrasi Larutan Hara pada Budidaya Selada (Lactuca Sativa l. var. grand rapid) dengan Teknologi Hidroponik Sistem Terapung

ABSTRACT The objective of this research was determined the optimum nutrient solution concentration on lettuce growth and yield in Deep Pool Growing System (THST). The study was conducted from November 2005 to March 2006 at Deep Pool Growing System facilities, Danasworo Hydrogarden Ciapus, Bogor (S 6 o 38’.19.78”, E 106 o 45’44.52”). The study was arranged in Completely Randomized Design with four levels of nutrient solution concentration. These are control (without nutrient), EC 0.75 mS.cm -1 , EC 1.50 mS.cm -1 and EC 2.25 mS.cm -1 . The composition of AB Mix nutrient solution were as followed (ppm): NH 4 + 22.5, K + 429, Ca 2+ 180, Mg 2+ 24, NO 3 - 1178, SO 4 2- 108, H 2 PO 4 - 194, Fe 3+ 2.232, Mn 3+ 0.275, Zn 2+ 0.261, B 3+ 0.324, Cu 2+ 0.049 dan Mo 2+ 0.048. Lettuce growth and yield was quadratically increased with nutrient solution concentrations application from 0 to 2.25 mS.cm -1 . Base on total plant weight and marketable plant weight, recommendation range of optimum nutrient solution concentration for lettuce hydroponic production in THST was between 1.09-1.15 mS.cm -1 .

Process development for an inducible rituximab-expressing Chinese hamster ovary cell line.

Inducible mammalian expression systems are becoming increasingly available and are not only useful for the production of cytotoxic/cytostatic products, but also confer the unique ability to uncouple the growth and production phases. In this work, we have specifically investigated how the cell culture state at the time of induction influences the cumate-inducible expression of recombinant rituximab by a GS-CHO cell line. To this end, cells grown in batch and fed-batch cultures were induced at increasing cell densities (1 to 10 × 10 6 cells/mL). In batch, the cell specific productivity and the product yield were found to reduce with increasing cell density at induction. A dynamic feeding strategy using a concentrated nutrient solution applied prior and postinduction allowed to significantly increase the integral of viable cells and led to a 3-fold increase in the volumetric productivity (1.2 g/L). The highest product yields were achieved for intermediate cell densities at induction, as cultures induced during the late exponential phase (10 × 10 6 cells/mL) were associated with a shortened production phase. The final glycosylation patterns remained however similar, irrespective of the cell density at induction. The kinetics of growth and production in a 2 L bioreactor were largely comparable to shake flasks for a similar cell density at induction. The degree of galactosylation was found to decrease over time, but the final glycan distribution at harvest was consistent to that of the shake flasks cultures. Taken together, our results provide useful insights for the rational development of fed-batch cell culture processes involving inducible CHO cells. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 35: e2742, 2019.

Growth of melon cultivated in coconut fiber under different concentrations of nutrient solution

To evaluate the effects of applying different concentrations of the nutrient solution macronutrients in growth of melon cultivated in coconut fiber it was conducted this experiment uses the ‘Galia’ melon (Cucumis melo L., hybrid Babilonia RZ F1). The experimental design was a randomized blocks utilizing five treatments, which corresponded to different concentrations of macronutrients in nutritive solutions (corresponding to different levels of nutrient solution macronutrients) based on the standard solution for the melon proposed by Furlani: 100 (control), 75, 50, 25, and 12.5%, applied in five replications. The concentration of 50% provided higher production of dry matter of the aerial part and leaf area. The absolute aerial part growth rate showed different tendencies for levels being that concentration of 50% produced the best results. The relative growth rate of the aerial part and assimilation rate of the aerial part decrease with time for all concentrations of the nutrient solutions tested.

Culture of lily (Lilium sp.) ‘Table Dance’ in an aquaponic system

Aquaponics could be a sustainable crop production system to reduce the excess of fertilizers and pesticides that end up polluting the environment. This study was conducted in order to determine the effect of aquaponics nutritional treatments in growth and development of oriental Lilium sp. 'Table Dance'. Three aquaponics treatments were established: 1) aquaponics, 2) aquaponics + N, K, Ca and S in nutrient solution, and 3) aquaponics + foliar fertilization (FF). A hydroponics treatment (50% Steiner nutrient solution) was used as a control. Plant height, stem diameter, number of leaves, leaf area, fresh and dry weight, number of flowers and vase life were measured in plants, as well as pH, electrical conductivity, nutrient concentration in aquaponic nutrient solution and nutrient content in plant tissue. Length, width and weight of fish also were measured. Aquaponics + FF had negative effects on leaves and flowers and on plant quality. Aquaponics + N, K, Ca and S generated optimum nutrient concentrations in solution and in plant tissue, as well as optimum growth and development (leaf area, dry weight, fresh weight, number of flowers and vase life) of lilies, yielding a good standard for quality of flowers.

Development of an in vitro hydroponic culture system for wasabi nursery plant production—Effects of nutrient concentration and supporting material on plantlet growth

The growth of wasabi (Wasabia japonica Matsumura) plantlets was compared in four concentrations of standard Enshi nutrient solution (25%, 50%, 100%, and 150%) and two kinds of supporting materials (rockwool and vermiculite) using an in vitro hydroponic culture system for photoautotrophic micropropagation. After 28 days of culture, most of the growth parameters such as fresh weight and dry weight, shoot/root dry weight ratio, and leaf area ratio were highest in wasabi plantlets grown in 50% or 100% nutrient solution, and this enhancement was greater in vermiculite than in rockwool. Dissolved oxygen concentration decreased sharply in rockwool but only slightly in vermiculite during the course of the experiment, resulting in a dissolved oxygen concentration of 8 mg L−1 in the vermiculite and 6 mg L−1 in the rockwool. The highest root nitrogen concentration was observed at a nutrient concentration of 100% in vermiculite and rockwool. The highest net photosynthetic rates were observed on day 28 in vermiculite at nutrient concentrations of 50% and 100%. The growth of wasabi plantlets is depressed through a decrease in root water and nutrient uptake caused by low dissolved oxygen concentrations. These findings clearly demonstrate that a hydroponic system that incorporates a 50% or 100% nutrient solution concentration and vermiculite will allow high-quality wasabi plantlets to be propagated rapidly under photoautotrophic conditions.

Herbivory-induced overcompensation and resource-dependent production of extrafloral nectaries in Luffa cylindrica (Cucurbitaceae)

Extrafloral nectaries (EFNs) are nectar secretory structures involved in the indirect defense of plants. In the sponge gourd (Luffa cylindrica), EFNs commonly occur on the lower surface of leaf blades and stipules and remain functional until leaf senescence. To test the hypothesis that the development of EFNs is influenced by herbivore damage and resource availability, we grew Luffa cylindrica under different concentrations of Hoagland's nutrient solution (nutrient-poor conditions: 10%, 50%; and control condition: 100%) and two herbivory treatments (damaged and undamaged leaves). We collected ten leaves from treated plants to quantify leaf area and EFN density. Overall, leaf area increased and EFN decreased in damaged plants, but this significantly depended on nutritional status. In undamaged plants, EFN density tended to remain constant, whereas foliar area increased with nutrient input. Under herbivory, foliar area increased at 10% but decreased at 50 and 100% of nutrients in relation to undamaged plants, whereas EFN density tended to increase with nutrient availability to exceed undamaged plants under control concentrations. Plants under nutrient-poor conditions subjected to herbivory exhibited an increased foliar area, characterizing a compensatory mechanism. Our results suggest that herbivore-induced indirect defense is a damage- and resource-dependent response in Luffa cylindrica. These findings contribute to understanding the factors that modulate indirect defenses and plant-herbivore-environment interactions.

Effect of potassium fertilizer, either KNO3, K2SO4 or KCl, in a saline fertigation solution on the growth of Medjool date palm plants pot-grown in river sand or river sand/calcium carbonate

A pot trial was carried out to assess the effect of three fertigation nutrient mixtures on the growth of Medjool date palm plants. The plants were grown either in river sand or in a 20% calcium carbonate - 80% river sand mixture to approximate desert soil conditions. Each fertigation solution comprised all of the elements required for healthy growth. The source of potassium of each solution differed. The fertilizer sources for the nutrients besides potassium were the same. The nitrate to ammonium ratio was markedly greater in the solution made up using KNO(3). The concentration of each element in each solution was identical, except for a relatively small increase in the SO(4)(2-) concentration in the solution made up with K2SO(4) and a relatively small increase in Cl- concentration in the solution make up with KCl. These differences were unavoidable, being a consequence of the K source used. In addition, an equal amount of NaCl was added to each solution to render the solutions saline. The plants were fertigated three times a week. Growth was assessed in terms of plant height on a number of dates after planting, and top leaf-stem fresh weight, root fresh weight, number of compound leaves, or number of primary roots when the plants were lifted from the pots, two years after planting. The plants grew better in the sand-calcium carbonate mixture. No interaction was apparent with respect to medium type and fertigation solution. The plants fertigated with the solution made up with KNO(3) grew better than those fertigated with the solution made up with KCl or K2SO(4). They were of greatest height and showed prominence in the other growth parameters assessed. A difference in growth relating to whether KCl or K2SO(4) was the K source was not clearly apparent. It was concluded that the growth of Medjool date palm plants could be expected to be better when nitrate predominates over ammonium in applying fertilizers. To maximize nitrate in a fertigation solution or fertilizer mix, the obvious option available is to use KNO(3) as the K source in endeavoring to match solution nutrient concentrations with date palm nutrient demand. The use of nitric acid can also be considered.

Seed potato minituber production in an aeroponic system under tropical conditions: electrical conductivity and plant density

Most seed potatoes in Brazil are produced in beds, pots or boxes containing substrate, but the yields are low. Aeroponic systems are one strategy for increasing the yield. However, the concentration of nutrient solutions, managed by varying the electrical conductivity (EC), is of upmost importance and can alter plant responses. Plant density is another important factor for obtaining high yields. The objective of this study was thus to determine the effect of nutrient-solution EC and plant density on plant and seed potato production in aeroponic system. The experimental design was a randomized block with a split-plot design and four replicates, with plots for EC and subplots for plant density. Two potato cultivars were tested. The best ECs for “Agata” and “Asterix” were 2.1 and 1.7 dS m−1, respectively. The highest plant density (100 plants m−2) for both cultivars produced the highest minituber yield and economic feasibility.

Growth and Fruit Biochemical Characteristics of Three Strawberry Genotypes under Different Potassium Concentrations of Nutrient Solution

Abstract A nutrient solution experiment was performed to evaluate the growth, yield and fruit biochemical characteristics of strawberry under different potassium levels of nutrient solution. Potassium concentrations including 235 (control), 350, 450 and 600 mg L-1 were applied to three strawberry genotypes of Camarosa, Selva and Parus under hydroponic culture. In the three genotypes, the maximum leaf area was observed at 350 mg L-1 K, and the maximum shoot fresh weight was either at 350 mg L-1 (in Camarosa and Parus) or at 400 mg L-1 (in Selva). In Selva, higher yield was produced by higher K concentrations than control (17-33%) and in Camarosa, the maximum yield was produced at 350 mg L-1 (16%), whereas fruit yield in Parus was not affected by K concentrations. In Selva and Parus application of 350 mg L-1 potassium produced more fruits than control. The maximum fruit vitamin C content in Camarosa and Selva was at 350 mg L-1, and in Parus at 450 mg L-1, while the significant lowest in three genotypes was at 600 mg L-1. Fruit titratable acidity and pH in Camarosa and Selva, and fruit TSS in Parus were not affected by K levels. Fruit total soluble solids (TSS) in Camarosa and Selva were maximum in 350 and 450 mg L-1. Increasing K concentrations of nutrient solution increased leaf and fruit K concentration than control. The results indicate that overall plant growth and fruit quality of three strawberry genotypes were increased by 350 mg L-1 potassium, while application of 600 mg L-1 reduced most traits than control. The Selva genotype had also a better response to higher concentration of K than two other genotypes.

Effects of Nutrient Solution Concentration and Daily Light Integral on Growth and Nutrient Concentration of Several Basil Species in Hydroponic Production

Our objective was to quantify the effect of mineral nutrient concentration of a nutrient solution on the growth of basil species and cultivars grown under high and low photosynthetic daily light integrals (DLIs). Sweet basil (Ocimum basilicum ‘Nufar’), lemon basil (O. ×citriodorum ‘Lime’), and holy basil (O. tenuiflorum ‘Holy’) seedlings were transplanted into nutrient-film technique (NFT) systems with different nutrient solution electrical conductivities (EC; 0.5, 1.0, 2.0, 3.0, or 4.0 dS·m–1) in greenhouses with a low (≈7 mol·m–2·d–1) or high (≈15 mol·m–2·d–1) DLI. Although nutrient solution EC did not affect growth and morphology, increasing DLI did. For example, when sweet basil was grown under a high DLI, the fresh and dry weight, height, and node number increased by 144%, 178%, 20%, and 18%, respectively, compared with plants grown under the low DLI, and branching was also stimulated. In contrast, DLI had little effect on tissue nutrient concentration, although nutrient solution did. Most tissue nutrient concentrations increased with increasing EC, with the exception of Mg and Ca. For example, N in sweet basil increased by 0.6% to 0.7% whereas Mg decreased by 0.2% as EC increased from 0.5 to 4.0 dS·m–1. Across treatments and basil species, tissue nutrient concentrations were generally within recommended ranges with no visible deficiencies. Based on our results, nutrient solution concentrations for hydroponic basil production can be selected based on factors such as other species grown in the same solution or by reducing fertilizer inputs.

Depicting the physiological and ultrastructural responses of soybean plants to Al stress conditions

Aluminium (Al) is a toxic element for plants living in soils with acidic pH values, and it causes reductions in the roots and shoots development. High Al concentrations can cause physiological and structural changes, leading to symptoms of toxicity in plant tissue. The aim of this study was to describe the Al toxicity in soybean plants through physiological, nutritional, and ultrastructure analyses. Plants were grown in nutrient solution containing increasing Al concentrations (0; 0.05; 0.1; 1.0, 2.0 and 4.0 mmol L−1). The Al toxicity in the soybean plants was characterized by nutritional, anatomical, physiological, and biochemical analyses. The carbon dioxide assimilation rates and stomatal conductance were not affected by the Al. However, the capacity for internal carbon use decreased, and the transpiration rate increased, resulting in increased root biomass at the lowest Al concentration in the nutrient solution. The soybean plants exposed to the highest Al concentration exhibited lower root and shoot biomass. The nitrate reductase and urease activities decreased with the increasing Al concentration, indicating that nitrogen metabolism was halted. The superoxide dismutase and peroxidase activities increased with the increasing Al availability in the nutrient solution, and they were higher in the roots, showing their role in Al detoxification. Despite presenting external lesions characterized by a damaged root cap, the root xylem and phloem diameters were not affected by the Al. However, the leaf xylem diameter showed ultrastructural alterations under higher Al concentrations in nutrient solution. These results have contributed to our understanding of several physiological, biochemical and histological mechanisms of Al toxicity in soybean plants.

تأثير إضافة المخصبات الأحيائية والرش بالمحلول المغذي كاليبور في نمو شتلات الرمان صنف Wonderful

نفذت التجربة في أحد الحقول التابعة لقسم البستنة وهندسة الحدائق /كلية الزراعة - جامعة ديالي للمدة 2016- 2- 24 لغاية 2017- 6- 1على شتلات رمان صنف Wonderful بهدف معرفة تأثير المعاملة بخليط من المخصبــات الأحيائيــة والرش بالمحلول المغذي كاليبور في صفات النمو الخضري لشتلات الرمان صنف Wonderful. استخدمت شتلات رمان بعمر سنتين متساوية الحجم قدر الامكان وأضيف المخصب الأحيائي الحاوي على بكتريا من النوعين Azospirillum brasilense وPseudomonas flourescense إلى وسط النمو المخصص لكل شتلة بتراكيز0، 10، 20غم. نبات- 1 بتاريخ 2016/2/24 ورشت الشتلات بأربعة تراكيز من المحلول المغذي (كاليبور) (7، 5، 3. 5، 0 مل. لتر- 1)ونفذت التجربة باستخدام تصميم القطاعات كاملة التعشية(RCBD ويمكن تلخيص نتائج التجربة بالآتي: 1- أدت إضافة المخصب الاحيائــي إلى زيادة معنوية في جميع معايير النمو الخضرية للشتلات قياساً بمعاملة المقارنة وأعطى المستوى الثالث من المخصب أعلى القيم لمتوسط الزيادة في قطر الساق الرئيس وطوله والمحتوى النسبي للكلوروفيل في الأوراق عند كلا موسمي النمو. أدى الرش بالمحلول المغذي كاليبور إلى إحداث زيادة معنوية في جميع معايير النمو الخضرية ولكلا موسمـــي النمو، ولم يختلف التركيز الثاني والثالث من المحلول عن بعضهما معنويا في جميع الصفات الخضرية ولكلا موسمي النمو (باستثناء صفة قطر الساق في الموسم الثاني)، وأزداد التأثير الايجابي في الصفات السابقة عند تداخل العاملين (المخصب الأحيائي والمحلول المغـذي) وحقق التداخل بين التركيزين الثاني والثالث من المحلول المغذي مع المستوى الثالث من المخصب الاحيائي أعلى مقدار للزيادة في جميع الصفات الخضرية قياساً بمعاملة المقارنة. 2- أدت إضافة المخصب الأحيائي بجميع مستوياته إلى إحداث زيادة معنوية في تركيز النتروجين والفسفور في الأوراق في كلا موسمي النمو قياساً بمعاملة المقارنة. أدى الرش بالمحلول المغذي بالتركيزين الثاني والثالث إلى حصول زيادة معنوية في العناصر الغذائية NP في الأوراق عند كلا موسمي النمو قياساً بمعاملة المقارنة. كما حقق التداخل بين المستوى الثالث من المخصب الاحيائي والتركيز الثاني من المحلول المغذي والمستوى الثاني من المخصب الاحيائي مع التركيز الثالث من المحلول المغذي اختلافا معنوياً في تركيز النتروجين في الأوراق موسمي النمو الأول والثاني على التوالي قياساً بمعاملة المقارنة التي سجلت أقل نسبة في حين سجلت معاملة التداخل بين المستوى الثالث للمخصب والتركيز الثالث من المحلول المغذي أعلى نسبة مئوية في تركيز الفسفور في الأوراق عند كــلا موسمــي النمو قياساً بمعاملــة المقارنة التي حققت أقل نسبة مئوية.

Effect of various phosphorus and calcium concentrations on potato seed tuber production

ABSTRACTAlthough the effects caused in plants by the calcium (Ca)–phosphorus (P) interaction in calcareous soils are well documented, very few studies report on such effects in nutritive solutions or hydroponic cultivation. In a sand and perlite (1:1 volume) hydroponic system, effects of various P (21, 42, and 63 ppm) and Ca (120, 180, and 240 ppm) concentrations on potato tuberization were studied. A factorial experiment based on a completely randomized design with three replications was conducted. For maximum tuber yield and tuber number production, 21 and 42 ppm P was sufficient, respectively. Increase in P and Ca concentrations in nutrient solutions in early growing season resulted in an increase in shoot and root weight, leaf area, and shoot length linearly, but tuber yield and tuber number did not follow this trend. The maximum tuber specific gravity and total solid percent were also observed in 42 ppm P. The highest tuber number and tuber yield were observed in 120 ppm Ca concentration.

Using Growth and Ionic Contents of Wheat Seedlings as Rapid Screening Tool for Salt Tolerance

High germination percentage with vigorous early growth is preferred for harvesting good wheat stand under saline soils. Therefore, an attempt for rapid screening of wheat genotypes for salt tolerance was made in this study. Eleven wheat genotypes including salt tolerant check Kiran-95were subjected to salinity (120 and 160 mMNaCl) along with non-saline control. Results showed a gradual decrease in seed germination and restricted seedling growth in tested wheat genotypes in response to increasing NaCl concentration in nutrient solution. Among the genotypes, NIA-AS-14-6 and NIA-AS-14-7 exhibited more sensitivity towards the salt stress at the germination stage but NIA-AS-14-6 performed quite satisfactorily later on at the seedling stage. Wheat genotypes NIA-AS-14-2, NIA-AS-14-4, NIA-AS-14-5, NIA-AS-14-10, and Kiran-95 showed better performance in term of root-shoot length, plant biomasses (fresh and dry), K+:Na+ ratio with least Na+ content, and high accumulation of K+ at higher levels of NaCl stress. On the basis of overall results, the categorization of genotypes was carried out as sensitive, moderately tolerant, and tolerant. Wheat genotypes NIA-AS-14-2, NIA-AS-14-4, NIA-AS-14-5, NIA-AS-14-10, and Kiran-95 grouped as tolerant, moderately salt tolerant group comprised of NIA-AS-14-1, NIA-AS-14-3, NIA-AS-14-6, and NIA-AS-14-8, whereas, NIA-AS-14-7 and NIA-AS-14-9 were found sensitive to salt stress. Principal component analysis revealed that components I and II contributed 70 and 16.5%, respectively. All growth parameters are associated with each other except RDW. In addition to growth traits, low Na+ and improved K+ content with better K+:Na+ ratio may be used for screening of salt tolerance in wheat as potential physiological criteria.

Development of Automatic Mixing Process for Fertigation System in Rock Melon Cultivation

This work proposed an automatic mixing system of nutrient solution for rock melon fertigation according to the required electrical conductivity (EC) level. Compared to the manual practice, this automatic system will ensure continuous supply of mixed nutrient solution without the need to daily check and mix new nutrient. Thus, this easy to use and low cost automatic system will reduce the burden of the farmers. This system uses an EC sensor to automatically check the concentration level of the mixed nutrient solution. Other than that, the system only consists of electronic pumps for mixing process and an Arduino board as the controller. The controller will monitor the EC level and run the mixing process when the EC level is below the required level. By calibrating the EC sensors, the test shows that the automatic mixing system is able to accurately keep the mixed nutrient solution concentration in a 400 L mixing reservoir at several required levels.