Nitrogen and calcium fertilization on the growth and development of gerbera cultivated in pots for cut flowers

ABSTRACT Gerbera is a flowering species with relevance to the cut flower market. Understanding nutritional requirements of the species is important to improve fertilization procedures. In the present work, our objective was to evaluate the influence of different doses of nitrogen (N) and calcium (Ca) on the growth and development of gerbera cultivated in pots as a cut flower. The experiment was conducted in a protected environment in a bifactorial design, with an additional treatment consisting of the combination of three N (0.07, 0.15 and 0.2 g L-1 substrate) and Ca (0.02, 0.03 and 0.04 g L-1 substrate) doses applied every 15 days. Control plants were not supplemented with either N or Ca. No significant interaction between N and Ca doses was observed. The highest number of flower stalks was obtained with 0.15 g N L-1 substrate and 0.04 g Ca L-1 substrate. Flower diameter, plant leaf area and total chlorophyll contents were at a maximum of 0.14 g N L-1 substrate and 0.04 g Ca L-1 substrate. N and Ca doses influenced in an independent manner the growth and development of gerberas as a cut flower cultivated in pots, and we determined that its fertilization should occur every 15 days with 0.34 g N L-1 substrate and 0.04 g Ca L-1 substrate.

Pengaruh Pupuk Kalsium dan Kalium terhadap Pertumbuhan dan Kualitas Hasil Sawi Hijau (Brassica rapa L.)

Mustard (Brassica rapa L.) is one of vegetable that cultivated and consumed by people in Indonesia regions. Using calcium fertilizer in mustard cultivation is less important, so that it is done when symptoms of calcium deficiency affect the quality of crop yield such as tip burn. Calcium fertilization could overcome calcium deficiency, but plant will undergo potassium deficiency as side effect. Foliar application of calsium fertilizer was used to avoid negative interaction between calcium and phosphate in the soil so that good quality yield and growth could be produced. A research was conducted on August-October 2019 at Kebun Percobaan Tri Dharma, Agriculture Faculty, Gadjah Mada University, Banguntapan, Bantul, Yogyakarta. The research used RCBD with two factors which were the concentration of calcium fertilizer (0, 2, 4, and 6 g/l) and the second factor was the dosage of KCl fertilizer (0, 100, 200, and 300 kg/ha). Concentration showed amount of calcium fertilizer mixed in a liter of water and dosage showed amount of fertilizer applied per plant. Result of the research showed that interaction between calcium concentration and phosphate dosage did not increase mustard growth and yield but had potensial in increasing texture and taste of mustard by applying 4 and 6 g/l calcium concentration with 100 kg/ha phosphate dosage, while 2 and 4 g/l calcium concentration with 200 kg/ha dosage could increasing sweet taste in mustard. Calcium fertilizer concentration increased mustard consumption index. The more amount of phosphate fertilizer dosage applied (> 300 kg/ha) could decrease mustard fresh weight

Calcium in the mineral nutrition of yellow passion fruit cultivated in lined pits and with saline water

ABSTRACT Nutritional status is an important tool in salinity management, because salt stress interferes with both the absorption and the assimilation of mineral nutrients by plants. The objectives of this experiment were to evaluate the effects of water salinity, lateral protection of pits against water losses and calcium doses on the leaf concentration of macronutrients and sodium of yellow passion fruit cv. BRS GA1. The treatments were arranged in a randomized block design in split plots in a 2 × (2 × 5) factorial scheme, corresponding to water salinity (0.3 and 4.0 dS m-1) in the main plot, and the combinations between lateral protection of pits (without and with) and calcium doses (0, 30, 60, 90 and 120 kg ha-1) in the subplots. Leaf concentrations of macronutrients and sodium were determined at the phenological stage of full flowering. Irrigation of yellow passion fruit with 4.0 dS m-1 water decreased the leaf concentrations of macronutrients. The lining of the pits compromised macronutrient concentration in the plants. Calcium fertilization is recommended for yellow passion fruit cultivated in Entisol with low calcium concentration at the dose of 60 kg ha-1, because it raises nitrogen and calcium concentrations in plants irrigated with non-saline water and magnesium and sulfur concentrations in those irrigated with saline water. Calcium attenuates salt stress because it promotes the accumulation of macronutrients in yellow passion fruit under saline conditions.

Influence of a Selenium Biofortification on Antioxidant Properties and Phenolic Compounds of Apples (Malus domestica)

Biofortified apples seem to be a suitable produce. In this study, different selenium forms and application levels were applied to the two apple varieties ‘Golden Delicious’ and ‘Jonagold’, grown in the years 2017 and 2018 in order to increase the selenium uptake within a typical Western diet. It was shown that the biofortification, which was performed as a foliar application implemented in usual calcium fertilization, led to significantly increased selenium contents in the fruits. Furthermore, biofortification affected the total phenolic content (TPC), the polyphenol oxidase activity (PPO), as well as the antioxidant activity (AOA), the latter measured with the two well-known assays Trolox Equivalent Antioxidant Capacity Assay (TEAC) and Oxygen Radical Absorbance Capacity Assays (ORAC). The varying selenium forms and application levels showed a differing influence on the parameters mentioned before. Higher fertilizer levels resulted in higher selenium accumulation. It was found that PPO activity fluctuates less in biofortified apples. With regard to TPC, selenate led to higher amounts when compared to the untreated controls and selenite resulted in lower TPC. AOA analysis showed no clear tendencies as a result of the selenium biofortification. In the case of ‘Jonagold’, a higher AOA was generally measured when being biofortified, whereas, in the case of ‘Golden Delicious’, only one form of application led to higher AOA. Additionally, differences in the amount of major phenolic compounds, measured with High Performance Liquid Chromatography Mass Spectrometry (HPLC-DAD-ESI-MSn), were observed, depending on the conditions of the biofortification and the variety.

Effect of calcium fertilization on silver vase bromeliad (Aechmea fasciata)

The present study aimed to evaluate the effect of different concentrations of calcium on growth and development of silver vase bromeliad (Aechmea fasciata). Plants were fertilized three times a week with nutrient solutions formulated with HA solution (Hoagland and Arnon, 1950) modified with 0.25, 2.5, 5, 7.5, 10.0 or 12.5 mM Ca applied into the tank. After 90 days of experimentation, biometric and biomass measurements of root and shoot systems, and chemical analysis of leaves were assessed. The results showed that the concentration of 12.5 mM Ca in nutrient solution is recommended for silver vase bromeliad fertilization.

Saline Water, Pit Coating and Calcium Fertilization on Chlorophyll, Fluorescence, Gas Exchange and Production in Passion Fruit

In plants sensitive to salinity, such as passion fruit, irrigation with saline water can cause physiological disturbances and reduce fruit production, necessitating the use of cultural practices that mitigate saline stress. The objective of this study was to evaluate the effects of water salinity, pit coating with high-strength polyethylene film, and calcium fertilization on the physiological and productive aspects of passion fruit ‘BRS Gigante Amarelo’. The treatments were arranged in split plot in the scheme 2WS × (2LP × 5DC), corresponding to water salinity (0.3 and 4.0 dS m-1) as the main plot, side coating of pits (without and with) doses of calcium (0; 30; 60; 90 and 120 kg ha-1). During the flowering phase, we evaluated leaf chlorophyll indices, fluorescence kinetics, and gas exchange. The increase in calcium doses up to 60 kg ha-1 increased leaf chlorophyll and quantum efficiency. The stomata did not restrict gas exchange, but salinity resulted in reduced net photosynthesis and plant production. The lateral coating of the pits intensified the reduction in salinity-promoted production, while calcium mitigated the effects of the salts. Entisol cultivated with passion fruit should not be irrigated with saline water of 4.0 dS m-1; lateral pit coating is not advised. In an Entisol with an initial calcium level of 1.92 cmolc dm-3, the recommended application dose is 60 kg ha-1 for passion fruit cultivation.

The Relationship between Transpiration and Calcium Fertilization on Mangosteen (Garcinia mangostana L.) Seedlings

The availability of nutrients in plants depends on the ability of plants to absorb nutrients from the soil. One of the processes absorbed by plants is by the presence of the transpiration process. Good transpiration will provide enough nutrients for plants which increase the productivity and quality of mangosteen. One of the quality standards of mangosteen fruit for export quality is the free from yellow sap contamination. It can be possible that transpiration can improve the quality of mangosteen fruit by applying fertilization. In this study Ca fertilization was carried out on mangosteen seeds, where this study aims to investigate the effectiveness of Ca uptake by mangosteen plants with the level of water loss by transpiration. This research was conducted in November 2016-March 2017 at the Leuwikopo Experimental Garden, Bogor Agricultural University. Morphological observations were carried out in its Experimental Garden and the Postharvest Laboratory whileanalysis of calcium content of plant tissue was done at the Department of Agronomy and Horticulture, Bogor Agricultural University. Data obtained then were analyzed using ANOVA test. If the results were significant, Duncan Multiple Range Test (DMRT) was then tested at 0.05 probability level. The results revealed that the transpiration rate of mangosteen plants from several treatments showed a significant difference, the transpiration rate was higher, especially in fertilized plants. The size of the 12th leaf, plants treated with fertilizer have a larger size than the treatment without fertilization. Fertilizing and providing enough water can maintain the growth of the plants.