Application Of Potassium Sulphate Research Articles

Optimizing Strawberry Growth and Fruit Quality through Fertigation Frequency and Foliar Application of Potassium Sulfate

Optimizing Strawberry Growth and Fruit Quality through Fertigation Frequency and Foliar Application of Potassium Sulfate

Influence of Plastic Mulch Colors and Application of Potassium Sulphate on Strawberry cv. Camarosa in Polyhouse

Influence of Plastic Mulch Colors and Application of Potassium Sulphate on Strawberry cv. Camarosa in Polyhouse

Performance of potato cultivars as a function of foliar application of potassium sulfate

The application of potassium fertilizers is an essential practice to obtain a high yield, especially in vegetables such as potatoes. The potato has high efficiency in the absorption and accumulation of nutrients. Thus, the objective was to evaluate, under the conditions of the Cristalina—Goiás, Brazil, the influence of time of foliar application of potassium sulfate in potato development. The experiments were carried out from March to June 2017, using Agata and Atlantic potato cultivars; and from June to October 2017, using Atlantic potato cultivar. The statistical method used was the randomized complete block design, with six treatments (without application; at 42; at 56; at 42 and 56; at 56 and 70; at 42, 56, and 70 days after planting) and four repetitions. At 75 days after planting the leaves of experimental plots were sampled to quantify the macro and micronutrients content. At the end of the experiments, tuber yield and qualitative characteristics were evaluated. The Atlantic cultivar showed a greater accumulation of nutrients than the Agata cultivar, in the March to June cultivation. The best productive performances of special class are related to application at 42, 56, and 70 days after planting in the cultivar Agata, at 56 and 70 DAP in the cultivar Atlantic (cultivation from June to October), and at 42 and 56 days after planting in Atlantic (cultivation from March to June). The treatments that stood out in the special class also reflect greater soluble solids in relation to the control for the cultivar Atlantic.

Improvement of frost tolerance in tomato by foliar application of potassium sulphate

The study aimed to determine the mean low-temperature exotherms (LTE) of the shoot tip of the Ömür F1, Cuma F1, Safir F1, VT-1770, Elibol F1, and Adelya F1 tomato cultivars and Yerli-14 and Yerli-24 local tomato genotypes. Moreover, this investigation intended to specify the most effective dose of potassium sulfate with its efficacy time by applying four different doses of potassium sulfate (K2SO4) foliar fertilizer on the most and least tolerant cultivar. The mean LTE of the shoot tip of seedlings was determined by using differential thermal analysis (DTA). In the second part of the study, 0%, 0.5%, 1%, 1.5%, and 2% dosage of K2SO4 foliar fertilizer were applied on the least and most tolerant cultivars with the intent of identifying the most effective dose increasing frost tolerance. It was also stated how long the ideal fertilizer dosage would be effective. DTA method may be effectively used in the determination of frost tolerance in tomatoes. VT-1770 was found the most tolerant cultivar while Safir F1 was the least tolerant. In the study, 1% fertilizer dose was found the most effective dose among the 0%, 0.5%, 1%, 1.5%, and 2% studied doses of K2SO4 foliar fertilizer after applying on Safir F1 and VT-1770 tomato seedlings. The dose of 1% K2SO4 fertilizer offered considerable frost resistance after 24 and 72 h later while slightly losing its efficacy after 120 h later as compared to each other after 1% application of fertilizer dose applied on Safir F1 and VT-1770 tomato seedlings. Present study revealed that the foliar application of K could be applied to enhancing frost tolerance in tomatoes.

Comparative evaluation of sulphur sources on growth, yield and quality of garlic (Allium sativum L.)

Sulphur is a prime nutrient in Allium crops. Garlic fertilization with ammonium-based sulphur fertilizers in low pH soils is being practiced by farmers that culminate the soil acidity, which has an adverse effect on plant growth. Hence a field experiment was conducted at Horticultural Research Station, Woodhouse farm, Ooty, the Nilgris in 2021 to evaluate the appropriate sulphur sources and their levels for garlic at acidic hilly soil using four sulphur sources viz., potassium sulphate, magnesium sulphate, zinc sulphate and ammonium phosphate sulphate and three levels viz., 0, 40, 60 kg ha-1. Garlic variety Ooty 2 was used as test crop. The results revealed that application of magnesium sulphate @ 60 kg ha-1 produced the highest plant height, leaf numbers, clove numbers bulb-1, neck thickness, polar diameter, equatorial diameter, the weight of 10 cloves, fresh weight, dry weight and bulb yield (16.78 t ha-1) of garlic. Quality parameters viz., total soluble solids, ascorbic acid and total phenols of garlic bulbs were improved by the application of potassium sulphate @ 60 kg ha-1. Sulphur source of Magnesium sulphate had a minimal effect of rendering acidity to soil measured in terms of pH (4.74) and exchangeable acidity (0.22 meq 100 g-1). Hence, the promising source for acidic hilly soil and garlic crop was found to be magnesium sulphate @ 60 kg ha-1 followed by potassium sulphate @ 60 kg ha-1. This particular investigation focuses not only on yield improvement but also on maintaining soil quality of the area.

Migration of Chlorine in Plant-Soil-Leaching System and Its Effects on the Yield and Fruit Quality of Sweet Orange.

Chlorine (Cl) is indispensable for the growth of plants. While rarely systematic reports are available for the effect of Cl-containing fertilizers on citrus production. This study aimed to investigate the impacts of various Cl-containing fertilizers on the nutrients in the leaves, the yield and quality of sweet orange, and the Cl migration in the plant–soil–leaching system. A 5-year field experiment (2016–2020) with five Cl treatments (0, 75, 150, 450, and 900 kg ha−1), and soil core lysimeter test with five Cl levels (0, 150, 225, 300, and 450 kg ha−1) were carried out. The results showed that 77.0% of Cl leached into above 60 cm deeper soil layer, with calcium as the main accompanying ions, resulting in less Cl being absorbed by the citrus plants. The content of Cl in the leaves and soil was enhanced by the increasing input of Cl-containing fertilizer, without yearly increased characteristics, under a mean annual rainfall of 1,474 mm. Chlorine significantly increased the yield (13.24–37.8 9%), fruit weight, and vitamin C (Vc), in addition to enhancing the flavor and the juice yield of sweet orange via improving the absorption of N and K. Moreover, the long-term application of potassium sulfate has elevated the accumulation of sulfur in the soil and in leaves; it is becoming a potential risk factor for citrus production. Taken together, the application of Cl-containing fertilizer in sweet orange is feasible, and trace absorbance of Cl could improve the yield and fruit quality of sweet orange.

Vegetative Growth and Ion Relations in Soybean with Potassium Sulphate Application under Saline Environment

Aims: To evaluate the effect of K2SO42- application on growth of soybean cultivars besides chemical parameters under salt stress.
 Study Design: Laid out the experiment in Complete Randomized Design in triplicates. Analyzed the data statistically by using the statistical software Statistix 8.1.
 Place and Duration of Study: The study was conducted in Soil Salinity and Bio-saline Research
 green house and in the laboratory of Land Resources Research Institute at National Agricultural Research Centre, Islamabad (under PARC), Pakistan for three months.
 Methodology: To study germination parameters under salt stress, NaCl was used @ 0, 100, 120 and 140 mmol L-1. At seedling stage, interactive effect among salt stress (0 and 4.5 dSm-1), potassium sulphate (KS) application @ 10 mmol L-1 and soybean (Cvs. NIBGE-301 and NIGBE-158) was recorded for growth and ion relations. 
 Results: Germination, biomass, bio vigor, mass vigor and sap vigor of the seedlings and ion relations were affected highly significantly (p≤ 0.01). Under interactive effect of KS and salt stress at vegetative stage, Na+/K+ in the plants declined with KS application. Sulphur and phosphorus concentration in the plants changed under the same conditions.
 Conclusion: Induced salt stress revealed germination, seed bio vigor, seeding mass vigor, and seedling sap vigor seedling and other vegetative parameters of soybean cultivars. Potassium sulphate application revealed genotypes differential response to ion relations and growth under salt stress. NIBGE-301 was more tolerant to salt stress and more responsive to potassium sulphate application than NIGBE-158.

Potassium: A Vital Macronutrient in Potato Production—A Review

Potassium (K) is a primary macronutrient for overall plant growth, yield potential, product quality and stress resistance of crops. Potato (Solanum tuberosum L.) crops require a high amount of potassium to achieve the ideal yield and quality. Therefore, the determination of optimum K rate and efficient source for potato is necessary because K affects crop physiological processes, dry matter production, cooking, and processing requirements. Through modeling on the pooled data extracted from 62 studies, the highest tuber yields might be obtained at an exchangeable soil K level of 200 mg kg−1 approximately, dependent on soil pH, texture, and organic matter. Through modeling on the data of 48 studies, it also revealed that application of potassium sulfate (K2SO4) and potassium chloride (KCl) at rates of 200 kg ha−1 and potassium nitrate (KNO3) at a rate of 100 kg ha−1 might achieve the ideal yield, implying the importance of K sources in potato production. However, these values (either soil exchangeable K content, or fertilizer rates) might not be applicable in a specific growing environment for a specific potato variety. It seems that there is no discrimination among split, pre-plant or in-season application of K, although pre-plant fertilization might be a trustworthy strategy for economic tuber yield. Owing to the luxury consumption of K by potato crop, a combination of factors, including soil exchangeable K level, petiole K concentration, crop removal amount, soil conditions, management practices, climatic conditions, and potato variety, should be considered in order to make rational K fertilizer recommendations.

Effect of Potassium Solubilizing Biofertilizers Application Compared to Potassium Sulfate on Growth and Some Physiological Traits of Radish (Raphanus sativus L.) under Drought Stress

Introduction: Plant growth promoting bacteria are beneficial microorganisms that produce plant resistance to a variety of biological and non-biological stresses, including drought, extreme temperatures, salinity, toxic metals, etc, and increase plant productivity and yield. The use of these microorganisms as biological agents in increasing soil fertility and improving agricultural productivity has been studied by many researchers, so a proper understanding of their effect on drought resistance can be effective in water resources management. Useful in field and reducing environmental effects of using chemical fertilizers. The purpose of this study was to investigate the effect of some bio-fertilizers on growth and some physiological and biochemical characteristics of red radish and in comparison with potassium sulfate application under drought stress. Material and Methods: In other to investigate the effect of application of bio-fertilizers containing potassium-soluble bacteria (Pseudomonas koreensis and Pseudomonas vancouverensis), phosphorus-solubilizing bacteria (Pseudomonas putida) and nitrogen-fixing bacteria (Pantoea agglomerans) on plant growth and function, this experiment was done with 10 treatments and three replications in the form of completely randomized design in greenhouse. Finally the statistical population consisted of 30 pots of 10 treatments and three replications for red radish. Drought stress was applied in such a way that the apparent symptoms of stress were seen in the plants and the amount of water used was the same for all plants. The experiment was carried out in greenhouses and nylon pots with a capacity of 6.5 kg were used. The soil was prepared using a calcareous soil of Zanjan University research field. Its absorption was less than critical. Organic matter content was 0.4% and lime equivalent was 14.1% pH of soil 7.57 and EC of abstract soil paste was 2.21. Pots were treated with municipal water for 25 days after planting. EC values of water was 400 µS / cm that irrigated the plants every three days. The desired bio-fertilizers were added to the pots with irrigation water. After 25 days, 15 pots of treatments 4 to 6 were subjected to drought stress. 40 days after planting before drying of the plants, weight, moisture content of plant tissue, leaf proline content, total free amino acid, and total soluble sugars in leaf extract were measured. Analysis of variance was performed using SAS software and LSD test at the 5% level was used to compare the means. Results and Discussion: Results of analysis of variance showed that the effect of different treatments on aerial fresh weight was significant at 1% level. Fertilizer treatments under stress and non-stress conditions significantly increased aerial fresh weight. Among non-stress treatments, the highest fresh weight was obtained from treatment 2 (10.03 g / pot) and the lowest was in control treatment (6.55 g / pot). Among the drought stress treatments with application of different fertilizers used, treatment 8 (9.19 g / pot) had the highest and treatment 6 (7.04 g / pot) had the lowest fresh weight. Application of potassium sulfate fertilizer increased the fresh weight of aerial part both under stress and non-stress condition. Potassium soluble bio-fertilizer alone and in combination with other bio-fertilizers increased radish aerial fresh weight, which was not significantly different from potassium sulfate fertilizer. In radish, drought stress affected the tuber fresh weight more. The radish plant uses the water of the tuber reserve in drought stress so that the leaves are less susceptible to stress. In non-stress conditions, application of potassium sulfate fertilizer and bio-fertilizers in radish increased yield. Potassium sulfate effect was greater. In stress conditions, the effect of bio-fertilizers was more than potassium sulfate in stress condition. The effect of potassium soluble bio-fertilizer application was almost identical with the combined application of different biofertilizers. Drought stress increased the concentration of proline, amino acids and soluble sugars in leaves and tubers of radish. Increasing concentration of these compounds indicated that plants were resistant to drought. Application of potassium sulfate and bio-fertilizers decreased these concentration and the effect of bio-fertilizers was more than that of potassium sulfate. The amount of ion leakage also increased under drought stress but leakage decreased by using potassium sulfate and bio-fertilizers. Drought stress also reduced the starch concentration in leaves and tubers of radish, which is a consequence of drought stress. Conclusion: In general, application of potassium sulfate and bio-fertilizers moderated the effects of drought stress and in some cases the effect of biofertilizers was greater. Integrated use of bio-fertilizers was not significantly different from the use of potassium soluble bio-fertilizer alone. So, the results of this study showed that the use of bio-fertilizers can be included in the plant nutrition program as a factor in reducing the negative effects of stress on plants.

The Effect of Potassium and Micronutrient Foliar Fertilisation on the Content and Accumulation of Microelements, Yield and Quality Parameters of Potato Tubers

The objective of this three-year study was to evaluate the effect of foliar application of dedusted potassium sulphate and chelated forms of microelements on the contents and accumulation of zinc (Zn), copper (Cu), manganese (Mn) and iron (Fe) as well as on the quality parameters of potato tubers at the stage of full maturity. Four treatments were analysed, including the control, where only nitrogen, phosphorus and potassium fertilisation was applied. Consistent with the experimental design adopted, other trials included: (I) Double foliar treatment with potassium sulphate in the combined dose of 8.6 K kg ha−1 (SOP); (II) double foliar treatment with micronutrients: 12 g Zn ha−1, 12 g Cu ha−1, 300 g Mn ha−1 and 500 g B ha−1 (Micro) and (III) combined application of SOP and Micro on two scheduled terms (SOP + Micro). Two potato varieties were tested: The French fries variety Zorba and the crisps variety Hermes. The experiment was arranged in a randomised complete block design with four replicates for each potato variety. Both the two-fold foliar spray with micronutrients and the treatment combined with the application of potassium sulphate resulted in the enhanced content and accumulation of the elements examined. The significant effect of the experimental factor was especially visible for the content and uptake of manganese and iron. Moreover, a highly significant relationship was determined between the tuber contents of protein and starch. The tuber quality parameters were most significantly conditioned by manganese and iron for the French fries variety and by zinc, copper and manganese for the crisps variety.

Effect of Foliar Application of Different Potassium Forms on the Growth and Flowering of Snapdragon (Antirrhinum majus L.) Plants

A pot experiment was conducted during 2018 and 2019 seasons in Sakha Horticulture Research Station, Kafr El-Sheikh Governorate, Egypt to study the effect of foliar application of potassium sulphate 50%, potassium nitrate 43% (1, 2 and 3 g/l water) and potassium silicate 38% (1, 2 and 3 ml/l water) on growth and flowering of snapdragon (Antirrhinum majus L.) plants. The results indicated that foliar spraying with the different potassium treatments significantly affected all the studied parameters in terms of plant height, number of shoots per plant, fresh and dry weight of plant, roots and flower, number of flowers per plant, spike length, total chlorophyll content andnutritional status (N, P, K and Si) as compared with control. Foliar spraying with potassium sulphate at 3 g/l water gave the significantly highest values of plant height, number of shoots per plant, fresh and dry weight of plant, roots and flower, number of flowers per plant, spike length and total chlorophyll compared to other treatments. Data showed also that, growth parameters, flowering characteristics and nutritional status were significantly increased with increasing the levels of potassium from 1 to 3 g/l water or ml/l water under the same source of potassium. So, it can be concluded that potassium foliar spray can be used as a partial substitution of the recommended soil amended potassium for increasing nutrients uptake and thus stimulating growth and flowering characteristics of snapdragon (Antirrhinum majus L.) plants and potassium sulphate at 3 g/l water can be used in this respect.

Foliar application of potassium to improve the freezing tolerance of olive leaves by increasing some osmolite compounds and antioxidant activity

Freezing damage is an important factor that limits olive production. The main aim of the present research was to investigate the possible impacts of the foliar application of potassium sulphate (K; K2SO4; 0.0, 0.5, 1.0, and 2.0 %) fertilization on the freezing tolerance (FT). Further, this research evaluated some physiological and biochemical changes of ‘Rashid’ olive (Olea europaea L.) at six sampling dates; these included November, December, January, February, April, and July. For this purpose, K was sprayed three times at 1-week intervals starting on 22 August 2016, on 16-year-old olives that had been located in a research orchard at Isfahan University of Technology (Iran), based on randomized complete block design. The results revealed that the effect of K sprays on the olives FT was significant at six stages of sampling. This was such that the highest (LT50 = −11.17 °C) and lowest FT (LT50 = −6.98 °C) was recorded in 2.0 % K-treated and control untreated olives during January, respectively. In addition, K application, particularly at 2.0 %, led to high increases of carbohydrate, proline, protein and total phenol concentration, antioxidant enzyme activity and DPPH (1, 1-diphenyl-2-picrylhydrazyl) scavenging capacity, as well as the ratio between unsaturated fatty acids and saturated fatty acids (UFA/SFA). It could be concluded that the foliar application of K could contribute to enhancing the olives FT by changing UFA/SFA ratio, in addition to the changes in other metabolites, like the accumulation of soluble carbohydrate, proline, protein, total phenol content and activation of the antioxidant system.

IMPACT OF FOLIAR APPLICATION OF POTASSIUM SULPHATE ON WEED DYNAMICS AND SOME PHYSIOLOGICAL ATTRIBUTES OF RAINFED BREAD WHEAT

An experiment to find out the wheat growth as affected by foliar application of potassium Sulphate (K2SO4) on different growth stages under rainfed conditions was conducted at the Agricultural Research Institute, Dera Ismail Khan, Pakistan. Potassium doses viz. 0, 12, 18, 24, 30 and 60 kg ha-1 were applied in foliar form at tillering, booting and heading stages of wheat. The course of study revealed that foliar application of K2O in booting stage produced maximum leaf area index (LAI), leaf area duration (LAD), crop growth rate (CGR), net photosynthesis rate (NPR) and grain yield, while its application at heading stage produced maximum net assimilation rate (NAR). Among different doses, the application of potassium at the rate of 60 kg ha-1 potassium at the rate of 60 kg ha-1 produced maximum growth and yield and its components during two consecutive cropping seasons of wheat crop while weed density (m-2), relative weed density (%), fresh weed biomass (g m-2) and dry weed biomass (g m-2) influenced non-significantly for both the years. These findings suggest that foliar application of potassium sulphate @ 60 kg ha-1 along with recommended dose of nitrogen (120 kg ha-1) and phosphorus (90 kg ha-1) is the most suitable for successful wheat production under rainfed conditions.

Effect of potassium sulfate on the physiological characteristics of canola cultivars in late season drought stress conditions

In order to reduce the damage caused by the late-season drought stress of canola, a factorial split-plot experiment was performed based on the randomized complete blocks design with three replications in Karaj, Iran. The treatments were Potassium sulfate in two levels, including application and non-application of potassium sulfate, irrigation at three levels including normal irrigation (control), restricted irrigation from the flowering and pod formation stage, as factorial were in main plots and winter canola cultivars including Opera, L72, KR1, GKH3705, GKH0224 were in subplots. The simple effect of irrigation and potassium sulfate on all of the studied traits and the simple effect of cultivar on all traits except chlorophyll b were significant. The interaction effect of irrigation × cultivar on soluble carbohydrate, stomatal resistance, proline content, chlorophyll a and total chlorophyll content was significant. The interaction effect of irrigation × potassium sulfate on the amount of soluble carbohydrates, stomatal resistance and proline content of leaves was significant. In irrigation interruption from the pod formation stage, the promising line of L72, and in irrigation interruption from the flowering stage, the Neptune cultivar exhibited the most positive effect of potassium application on the studied traits. As a result, the application of potassium sulfate in addition to the L72 and Neptune cultivars is recommended in areas similar to the tested area encountering the late-season drought stress.

IMPROVING FRUIT QUALITY OF WONDERFUL POMEGRANATE BY USING FOLIAR APPLICATION OF POTASSIUM, IRON AND BORON

This study was carried out during 2017 and 2018 seasons, in order to investigate the effect of single and combined application of potassium sulphate (K2SO4), ferrous sulphate (FeSO4) and boric acid (H3BO3) on fruit physical, chemical properties and maturation of Wonderful pomegranate trees grown in sandy soil under Minia Governorate conditions. Results showed that increasing the concentration of K2SO4 from 0.5 to 1.5%, FeSO4 from 100 to 200 ppm or/and H3BO3 was very effective in fruit weight (g). While, the three examined compounds significantly decreased fruit cracked (%) and fruit sunburned (%) during the two experimental season. Application of the three examined compounds together significantly surpassed than untreated control or each compound alone terms of improved fruit physical and chemical properties, while, juice total acidity was significantly decreased. For producing favorable fruit physical properties of Wonderful pomegranate grown under sandy soil, it is necessary to spray the trees with mixture of potassium sulphate at 1.5%, ferrous sulphate at 200 ppm and boric acid at 100 ppm three times yearly during the fruit growth cycle.

Effect of Nitrogen Levels and Foliar Application of Potassium Sulfate and Micronutrients on Growth and Yield of Maize Preceded By Wheat or Clover

Intensive crop rotation and imbalance fertilizer use have resulted in a wide range of nutrients deficiency in fields. For intensive cropping systems, the current recommended fertilizers rates need revision upwards with in balance ratio of vital micronutrients specific to crop to enhance stagnant yields. Two field experiments were carried out at the Agric. Exp. Sta., Fac. Agric., Cairo University, Egypt during 2014/2015 and 2016/2017 seasons to study the effect of preceding winter crops (Wheat or Egyptian clover), nitrogen levels (90, 120 and 150 kg N/fed.) and foliar minerals application (Control, potassiumsulphateand micronutrient compound of high zinc as well as their interaction) on growth and yield of Zea mays L. cv. single cross 131. The experimental design was split- split plot design with three replications. Results showed that maize planted after Egyptian clover provided the highest grain yield per plant (201.1 and 250.4 g), grain yield per fed. (3.474and3.487 ton) as well as harvest index (0.35 and 0.25 %) as compared to maize sown after wheat for both seasons, respectively. Increasing N rates from 90 to 120 kg/fed.and from 120 to 150 kg/fed.increased grain yield/plant by about 5.2% and 1.9% in the 1st season, corresponding to 2.9 % and 1.9% in the 2nd season, respectively. Increasing N rates from 90 to 120 kg/fed.and from 120 to 150 kg/fed increased grain yield/fed by about 24.6% and 12.8 % in the 1st season, corresponding to 25.9 % and 12.1 % in the 2nd season, respectively. Maize plants grown after Egyptian clover and receiving 150 kg N/fed.with the applied micronutrients and k foliarspray gave the highest grain yield/fed. (4.083 and 4.139 ton)in both seasons. The lowest value of grain yield/fed.was shown when maize was grown after wheat and receiving 90 kg N/fed.with foliar application of micronutrients and k sulfate in both seasons.Maize grown after Egyptian clover and receiving 120 kg N/fed.andfoliar application of micronutrients and k sulfate is recommended for maize production. On the other hand, maize grown after wheat withapplication of150 kg N/fed and foliar applicationof micronutrients and k sulfate is recommended for maize production.Regression analysis reveal the relation between the two variables, i. e., preceding crops (x) and Grain yield/fed (y) there was a linear relation, and, highly significant (P≤0.01) correlation coefficient (r=1) during the first and second seasons. Linear regression equation for N rates suggested that increase in one unit (30 kg/fed.) led to increase grain yield/fed.by 0.35 ton/fed.during the first and second seasons.

Potato response to silicone compounds (micro and nanoparticles) and potassium as affected by salinity stress

Salinity of irrigation water is an important limitation factor in crop production such as potato worldwide. Foliar application of anti-stress compounds containing mineral nutrients is one of the possible solutions for salinity mitigation. In this field experiment the effects of silicone compounds on potato (cv. Agria) performance was studied as a split plot based on randomised complete block design with three replications at Ferdowsi University of Mashhad, Iran, during 2016 cropping season. Treatments included irrigation salinity [0.3 (non-stress), 5, 8 and 12 dS.m–1] and foliar application of potassium sulphate (1000 ppm), sodium silicate nanoparticles (400 ppm) and silica (1000 ppm). Results indicated that salinity decreased transpiration rate, stomatal conductance, quantum yield of PSΙΙ, membrane stability index, carotenoids, tuber number per plant and tuber yield while it improved water use efficiency and tuber dry matter percentage. Foliar application of anti-stress compounds positively affected quantum yield of PSΙΙ, carotenoids content, DPPH radical scavenging activity, tuber number per plant, tuber yield and tuber dry matter percentage. Although, application of all compounds improved most biochemical and photosynthetic traits, but ameliorative effect of the two silicon compounds, especially sodium silicate nanoparticles was more evident. It seems that silicon application could be an effective strategy in reducing salinity effects and its efficiency will be increased when is used as nanoparticles.

Maize Grain Yield and its Quality as Affected by Previous Crop, Nitrogen Rate and Nutrients Foliar Application تأثیر المحصول السابق ومعدلات التسمید النیتروجینی والرش الورقی بالعناصر المغذیة على محصول الذرة وجودة حبوبه

Two field experiment was conducted to evaluate effect of preceding winter crop (Wheat and Egyptian clover), nitrogen levels (90, 120 and 150 kg N/fed.) and foliar minerals application (control, potassium sulphate, and micro-nutrient compound as well as their interaction) were carried out at Exp. Stat., Fac. Agric., Cairo Univ., Egypt during 2015 and 2017 growing seasons. Analysis of data showed that all parameters of Zea mays L. cv. single cross 131 significantly increased grain protein, carbohydrates and oil contents. The highest values of the previous parameters were obtained when maize was preceded by Egyptian clover, while the lowest ones were noticed after wheat. Results indicated that protein, carbohydrates and oil contents of maize grain and grain yields markedly increased with the increase in N rates from 90 to 150 kg /fed. The maximum value of protein, carbohydrates, oil contents as well as, their yields/fed. were recorded with foliar application of micronutrients + potassium. Results also indicated that maize grown after Egyptian clover and Micronutrients + K sulfate foliar application recorded maximum grain protein content (10.1 and 10.6 %), grain carbohydrate content (63.0 and 68.5%) and oil content (10.0 and 9.9 %) in both seasons, respectively, as well as, recorded maximum protein yield/fed. (0.364 and 0.389 ton) and oil yield/fed. (0.359 and 0.360 ton) in both seasons. Maize grown after Egyptian clover and received 120 kg N/fed. combined with nutrients foliar application of potassium sulphate and micro-nutrients are recommended for high maize grains, protein, carbohydrates and oil yields. On the other hand, maize grown after wheat and received 150 kg N/fed. and nutrients foliar application of potassium sulphate + micronutrients resulted in producing the maximum maize grain, protein, carbohydrates and oil yields.

Impact of saline water irrigation plus potassium sulphate application on growth and yield potential of pepper plants

The aim of this research was to investigate the impact of different saline water irrigation levels plus potassium sulphate (K2SO4) application on growth and yield potential of pepper plants. The treatments consisted of three saline water irrigation levels (2.5, 4 and 6 dS m-1) and tab water as control. Each treatment was supplemented with different levels of K2SO4 at (zero, 2 and 4 gm K2SO4 per plant), except for the control. Plant observations were collected to evaluate plant length, fruit number per plant, fruit yield per plant, stem water potential, plant transpiration, photosynthetic rate and dry matter of shoots and roots. Results of this study indicated that K2SO4 application played a positive impact on alleviating salinity stress and improving plant growth parameters mainly under saline water irrigation levels of 2.5 and 4 dS m-1 plus 2 gm K2SO4 compared to saline water irrigation treatments which were not supplemented with K2SO4.

Responding of Long Green Pepper Plants to Different Sources of Foliar Potassium Fertiliser

Abstract The aim of this study was to explore the efficiency of foliar potassium fertiliser relative to morphological, physiological and biochemical properties of hybrid long pepper (Capsicum annuum). Pepper plants were grown in a greenhouse and supplied with three sources of foliar potassium fertilisers, i.e., potassium-humate (1 g/L = 1,250 g/ha), potassium sulfate (1 g/L = 1,250 g/ha), and potassium chloride (1 g/L = 1,250 g/ha). Water served as control. The impacts of these treatments on the phytosynthetic parameters (photosynthetic rate, stomatal conductance, intercellular CO2, leaf carotenoids) and chlorophyll a and b, metabolic compounds and nitrogen, phosphorus and potassium were measured. The phytosynthetic parameters significantly improved by different foliar potassium application and the highest level of photosynthetic activity was noted in plants supplied with potassium sulfate, followed by potassium-humate and potassium chloride. Plant biomass accumulation, cholorophyll (a and b), and total yield showed larger increases in plants fertilised with potassium sulfate than those fertilised with potassium-humate; smallest increases occurred with potassium chloride. Concentrations of total sugars, carotenoids, chlorophyll (a and b), and endogenous level of nitrogen, phosphorus, and potassium contents in plants and fruits were possitively influenced by varying sources of potassium. The fruit color parameters and total soluble solid were also significantly increased with all foliar potassium treatments compared with control. Foliar application of potassium sulfate recorded the highest values and significantly increase all anatomical characters for leaf, stem and fruit of pepper plant.