Calcium Sprays Research Articles

Effect of Calcium Sources and Their Mode of Application on Growth and Plant Nutrient Uptake of Two Apple Varieties Grown under High Density Planting System

Apples grown in Kashmir province are famous globally, but lack of post-harvest storage facilities deteriorate its quality and market acceptability. Calcium deficiency in acid soils deceives apple fruit quality. Calcium helps to reduce the occurrence of physiological disorders; it also plays essential role to improve growth and quality of produce. Modes of calcium application and its different doses on two apple varieties was tested in 3 factorial randomized block design to improve yield and quality at Ambri Apple Research Centre, Sher-e-Kashmir University of Agricultural Sciences and Technology, Kashmir, India in 2022. Foliar application of calcium to apple is most effective method for escalating fruit calcium content and quality. Among sources and their mode of application calcium nitrate foliar application at the rate of 3, 4 and 5 gram per litre of water performed better than foliar application of calcium chloride at the rate of 3, 4 and 5 gram per litre of water in improving fruit nutrients and yield of Golden Delicious than Red Chief Camspur, whereas soil application of calcium nitrate showed least response to improve fruit nutrient and yield in both varieties. Fruit length and fruit diameter improved with each enhanced calcium concentration in both varieties by different calcium sources and their mode of application. The partitioning of nutrients in plant leaves and fruits differed significantly, and in both varieties were dependent on applied calcium rates, calcium sources and their mode of application. Calcium nitrate foliar spray performed better than calcium chloride foliar spray or soil application of calcium nitrate in improving fruit growth and quality. Our study did not find any adversity of dosage in plants whether applied as foliar or to soil. The best results were observed in foliar application of calcium nitrate @ 5 g per lit water for all the parameters in both the varieties. Results of research evidenced that preharvest calcium sprays increase growth and improved fruit quality that led to reduce deterioration in post-harvest storage.

Effect of Calcium Formulations to Increase Yield and Shelf Life of Manjri Naveen Grapes

The application of Calcium at veraison stage maintain the quality of grapes. Hence to evaluate the effect of Calcium formulations for increasing yield and the shelf life of Manjri Naveen grapes. The experiment was designed as randomized block design (RBD) having seven treatments and four replications (1 replicate = 4 vines). Three calcium formulations were used i.e. CaCl2, CaO, Ca(No3)2 as a dose of (2.5 g/l) and (5 g/l). Foliar application of calcium was done 10 days before harvest at veraison stage. Results obtained from the experiment showed the lowest weight loss was found in bunches of calcium oxide and calcium chloride spray treatments (8.14 %), (8.61 %) respectively, while the highest weight loss (10.36 %) occurred in untreated control. The PLW increased significantly at successive from 1.32 % on 1st day to 10.36 % on 7th day of storage at room temperature. CaO at 5 g/l recorded the lowest fallen berries 2.70 (%), followed by Ca(NO3)2 at 2.5 g/l recorded 3.38 (%). It might be due to calcium accumulated mostly in the rachis and less in the flesh during grape berry development. Yield and quality components like bunch weight, berry weight, total yield/vine, TSS, TSS/Acidity ratio were significantly influenced by calcium spray. Hence from this study it is concluded that the foliar application of CaO at 5 g/l was found to be effective for increasing the shelf life and yield of Manjri Naveen grapes.

Comparative Evaluation of Calcium Sources and their Mode of Use on Apple Production in Acidic Soil under High Density Plantation System

Apples grown in Kashmir province are extremely prone to deterioration, particularly in post-harvest storage. Calcium is amongst the vital mineral element deceiving apple fruit quality, predominantly in acid soils deficit in available calcium. Calcium in sufficient quantity helps to retain apple fruit firmness and reduces the occurrence of physiological disorders, it also plays essential role to improve yield and quality of produce. Modes of calcium application and its different doses on two apple varieties was tested to improve yield and quality at Ambri Apple Research Centre, Sher-e-Kashmir University of Agricultural Sciences and Technology, Kashmir, India. The direct application of calcium to apple as spray is most effective method for escalating fruit calcium content and quality. Among sources and their mode of application calcium nitrate foliar application performed better than foliar application of calcium chloride in improving fruit quality and yield of Golden Delicious than Red Chief Camspur, whereas soil application of calcium nitrate showed least response to improve fruit quality and yield in both varieties under acidic soil atmosphere. Physiological loss in weight at 30 days and 60 days after harvesting was lower in foliar applied calcium than soil calcium application. The significant variation in total sugar content and TSS of apple fruits were observed in different calcium sources and their mode of application. Calcium nitrate foliar spray performed better than calcium chloride foliar spray in improving fruit quality. Our study did not find any adversity of dosage in plants whether applied to soil or directly to plant and we did observe better yields and quality at higher calcium doses. Among varieties Golden Delicious performed better than Red Chief Camspur. Results of research evidenced that preharvest calcium sprays increase yield, improved fruit quality and reduced its deterioration in post-harvest storage.

Influence of Pre-harvest Application of NAA, Ca, and B on Fruit Drop, and Yield of Thailand Ber (Ziziphus mauritiana)

The present study was carried out to investigate the beneficial effects of the pre-harvest spray of NAA, calcium, and boron on fruit drop and yield of Thailand ber (Ziziphus mauritiana) at the Experimental Farm, Department of Horticulture, AAU, Jorhat-13 during 2022-2023. The treatment T4 i.e. spraying with NAA @ 20 ppm + B @ 0.5% resulted in maximum fruit set (4.68%), lesser fruit drop (53.28%), the highest yield per tree (18.12 kg/tree), yield per hectare (24.16 t), the maximum thickness of pulp (1.94 mm) and pulp weight (62.25 g). Spraying of NAA 20 ppm in combination with Boron 5% is the most profitable approach for minimizing fruit drop and maximizing production.

Response of strawberry to mulching, biofertilizer and calcium spraying and its effect on fruit traits

Response of strawberry to mulching, biofertilizer and calcium spraying and its effect on fruit traits

Effect of Packaging Type and Calcium Spraying on Some Chemical Traits of Seedless Pomegranate Variety Rawa

Effect of Packaging Type and Calcium Spraying on Some Chemical Traits of Seedless Pomegranate Variety Rawa

Mode of Action of Calcium in Reducing Macrocracking of Sweet Cherry Fruit

Rain cracking (hereinafter referred to as macrocracking) severely impacts the production of sweet cherry (Prunus avium). Calcium (Ca) sprays can reduce macrocracking, but the reported responses to Ca sprays are variable and inconsistent. The objective of this study was to establish the physiological mechanism through which Ca reduces macrocracking in sweet cherry fruit. Six spray applications of 50 mM CaCl2 had no effect on macrocracking (assessed using a standardized immersion assay) despite a 28% increase in the Ca-to-dry mass ratio. Similarly, during another experiment, there was no effect of up to nine Ca sprays on macrocracking, although the Ca-to-dry mass ratio increased as the number of applications increased. In contrast, CaCl2 spray applications during simulated rain (in a fog chamber) significantly reduced the proportion of macrocracked fruit. Additionally, immersion of fruit in CaCl2 decreased macrocracking in a concentration-dependent manner. Monitoring macrocrack extension using image analysis revealed that the rate of macrocrack extension decreased markedly as the CaCl2 concentration increased. This effect was significant at concentrations as low as 1 mM CaCl2. Decreased anthocyanin leakage, decreased epidermal cell wall swelling, and increased fruit skin stiffness and fracture force contributed to the decrease in macrocracking. There was no effect of CaCl2 on the cuticle deposition rate. Our results demonstrated that Ca decreased macrocracking when applied to a wet fruit surface either by spraying on wet fruit or by incubation in solutions containing CaCl2. Under these circumstances, Ca had direct access to the cell wall of an extending macrocrack. The mode of action of Ca in reducing macrocracking is primarily decreasing the rate of crack extension at the tip of a macrocrack.

Effect of humic acid, calcium and poultry waste on growth and yield of broccoli

A field experiment aimed to investigate the effect of humic acid, calcium spraying on the plant and poultry waste on growth and yield of broccoli in Abu Ghraib area within the Horticultural Department during 2019 season. The study utilized a randomized complete block design (RCBD). Humic acid to the soil at two levels (0 and 40 L ha−1), poultry manure at two levels (0 and 12 Mg ha−1), nitrogen at 96 kg N ha−1, phosphorous at 184 kg P ha−1, potassium added at 100 kg K ha−1. Calcium sprayed on the plants in the form of CaCl2 and CaSO4 at two levels (0 and 10 g L−1). Results showed effects of humic acid, incorporating poultry manure, plant calcium spraying, their interactions, on N, P and K in flowering leaves number, and plant yield. Nitrogen concentration in the flowering tablets reached 3.04%, phosphorus concentration in the flowering tablets was 0.47%, and potassium concentration in the flowering discs was 3.23%. Additionally, there was a notable increase in leaves number per plant (41.47 leaf plant−1) and plant yield reached 30.07 Mg ha−1, representing a remarkable of 143.87% compared to control.

Mycorrhizal colonization and calcium spraying modulate physiological and antioxidant responses to improve pepper growth and yield under salinity stress

Abiotic stresses, such as salt and drought, limit plant growth, reduce crop production, and pose the greatest challenge to the sustainability of agricultural development in arid and semi-arid countries. Arbuscular mycorrhizal fungi (AMF) and calcium can play an important role in alleviating the adverse effects of abiotic stresses on plants. Therefore, this study was conducted to evaluate the effect of two levels of mycorrhizal inoculation (inoculated seedlings and non-inoculated seedlings) and three levels of foliar spraying with calcium (0, 0.5%, and 1%), separately or in combination, on growth, physiology, and yield of salt-stressed pepper (Capsicum annuum L.). The experiment was conducted in an open field with saline soil and irrigation water, in a randomized complete block design with split plot arrangement. Mycorrhizal inoculation and calcium spray have been shown to facilitate nutrient uptake, modulate physiological responses, and activate the antioxidant system, enhancing salt stress tolerance and improving the growth and yield of salt-stressed pepper. Combined treatment plants grown from inoculated seedlings and sprayed with 1% Ca recorded the best results, alleviating salt stress-induced oxidative damage by activating the antioxidant system including antioxidant enzymes [Superoxide dismutase (SOD) and catalase (CAT)], and non-enzymatic antioxidants (ascorbic acid and phenols), reducing H2O2 and malondialdehyde (MDA) accumulation, enhancing physiological activities (relative water content (RWC %) and chlorophyll content), and improving nutrient balance (increasing N, P, K and reducing Na content), leading to increased pepper growth and yield parameters. Our results indicated that mycorrhizal inoculation and calcium spray can be recommended as a practical alternative and environmentally friendly approach to enhance plant tolerance to salt stress by improving nutritional status, physiological processes, and antioxidant activities, thus increasing the morphological and yield traits of stressed plants.

Response of three Cucumber cultivars to Calcium foliar feeding

A field experiment was carried out for the year 2022- 2023 in Al- Dahra region located within 45.25 longitude and 31.39 latitude to find out the response of cucumber plants to foliar spraying with different levels of calcium. The experiment included nine treatments in which three cultivars of cucumber were used, namely Maha, Saturn, and Ramie cultivars. Codes V1, V2 and V3 were taken, respectively, and three calcium levels (0, 100, and 200 mg/ L). A factorial experiment was applied using completely randomized blocks (R.C.B.D) with three replications. The averages were compared according to the (L.S.D) test at a probability of 5%. The two cultivars V2 and V3were significantly superior in the characteristic of dry weight, which did not differ from each other, as they recorded the highest averages of 63.19 and 64.34 g. plant-1 , while the cultivar V3 excelled in the characteristic (number of fruits, fruit weight, and yield of a single plant) as it gave averages for these characteristics, it amounted to (22.19 fruit per plant, 104.87 g per plant, and 2.314 kg per plant), respectively. Calcium spray treatment 200 mg/ L was significantly superior in traits plant height and dry weight, and the two highest averages were 172.0 cm and 70.03 gm.plant-1 , while there is no significant difference with calcium 100 mg/ L in the number fruits, weight fruit, and one plant yield. The two- way interaction had a significant effect on dry weight and fruit weight, as the mean of these two characteristics was 74.93 g. plant-1 and 115.42 g. fruit-1 .

Influence of pre-harvest calcium spray on fruit quality of apple cultivars during cold storage

Influence of pre-harvest calcium spray on fruit quality of apple cultivars during cold storage

Effect of calcium spray at flowering combined with post-harvest 1-MCP treatment on the preservation of grapes

These tests were carried out to find out how calcium and 1-MCP treatment affected the preservation of grapes, as grapes are highly susceptible to decay during post-harvest storage. The grapes were treated with 5 g/L calcium at the flowering stage, followed by 1 μL/L 1-MCP treatment after harvesting.When grapevines were treated with a combination of calcium and 1-MCP, the marketable fruit rate (At day 56 of storage, the 1-MCP + Ca2+ treatment group was still 93%, an increase of 29.03% compared to the control group.) and quality improved (At day 28 of storage, the VC content of the 1-MCP + Ca2+ treated group was 4.35 mg/100g, an increase of 25.01% compared to the control group.), while the fruit weight loss rate decreased (At day 56 of storage, the weight loss of the control group was 6.97%, an increase of 39.43% compared to the 1-MCP + Ca2+ treated group.).According to the experimental results, there are several reasons for this. First, in the early stages of fruit storage, the concentration of soluble pectin and soluble fiber, as well as the activities of pectinase and cellulase (related gene levels) were decreased. Secondly, the activity of antioxidant enzymes was increased, while MDA content was decreased. Third, during fruit storage, the respiratory intensity and ethylene release rate were reduced, as was the activity of energy metabolism enzymes. As a result, the aging and deterioration of the fruit during storage were delayed. Principal component analysis revealed that the calcium and 1-MCP combination therapy slowed the decline in grape berry quality, followed by the calcium-treated and 1-MCP-treated fruits. In contrast, grape berry quality declined the most rapidly in the control group.

Foliar Application of Chelated Sugar Alcohol Calcium Improves Photosynthesis and Tuber Quality under Drought Stress in Potatoes (Solanum tuberosum L.).

Drought stress is a major threat to sustainable crop production worldwide. Despite the positive role of calcium (Ca2+) in improving plant drought tolerance in different crops, little attention has been paid to its role in mitigating drought stress in potatoes. In the present study, we studied the effect of foliar chelated sugar alcohol calcium treatments on two potato cultivars with different drought responses applied 15 and 30 days after limiting soil moisture. The results showed that the foliar application of calcium treatments alleviated the SPAD chlorophyll loss of the drought-sensitive cultivar 'Atlantic' (Atl) and reduced the inhibition of photosynthetic parameters, leaf anatomy deformation, and MDA and H2O2 content of both cultivars under drought stress. The Ca2+ treatments changed the expression of several Calcium-Dependent Protein Kinase (StCDPK) genes involved in calcium sensing and signaling and significantly increased antioxidant enzyme activities, average tuber weight per plant, and tuber quality of both cultivars. We conclude that calcium spray treatments improved the drought tolerance of both potato cultivars and were especially effective for the drought-sensitive cultivar. The present work suggests that the foliar application of calcium is a promising strategy to improve commercial potato yields and the economic efficiency of potato production under drought stress conditions.

The Effect of the Combination of Organic Fertilizer and Spraying with Silicon and Calcium on the Growth and Production of Three Cultivars of Beet

Field experiments were carried out for the autumn season 2022- 2021 in the field of College of Agricultural Engineering Sciences - University of Baghdad - Jadiriyah Complex –Station A- to study a combination of organic fertilizer (Vermicompost) and cow manure as well as a control treatment (soil only) intertwined with Spraying with silicon, calcium and distilled water (control) in the growth and production of three cultivars of beet (Cylindra, Dark Red, Red) within the design of Completely Randomized Block Design at three replications, The number of treatments was 9 for each replicate. The means were compared according to the least significant difference (L.S.D) at a probability level of 5 %, the results were as follows:-The interaction treatment of the Vermicompost with calcium spraying in the number of leaves, the concentration of chlorophyll, the percentage of nitrogen and phosphorous), was significantly superior to the combination of Vermicompost with spraying silicon significantly (in the percentage of potassium, the concentration of silicon, the root yield, the leaf yield, the percentage of dry matter, phenols and sugars), at a rate of (387.67,3%.28 mg kg−1, 35.88 ton h−1, 50 ton h−1, 8.78%, 014% and 889%) respectively. As for the percentage of calcium, it was characterized by the combination treatment of cow manure with calcium spray, and the combination of cow manure with silicon spray was superior in T.S.S. and the percentage of fiber at 3.17 and 11.66% respectively for the Red variety.As for the variety Red Dark it was significantly superior to the mixture of the medium vericompost with silicon spray in the number of leaves, the concentration of chlorophyll and the percentage of nitrogen, the concentration of silicon, Root yield and leaf yield Percentage of dry matter T.S.S, phenols and sugars at (10 leaf plant−1, 82.2 mg 100 fresh wet−1, 3.53%, 313.00 mg kg−1, 36.35 ton h−1, 40.92 ton h−1, 6.86%, 11.03%, 0.16% and 845%) respectively, while the percentage of phosphorous and potassium, it was characterized by the combination of cow manure with silicon spray, and the combination of vermicompost with calcium spray was superior to the percentage of calcium and the percentage of fiber by giving it 2.19% and 2.50% respectively. As for the variety Cylindra it was significantly superior to the combination of the Vericompost with silicon spray in the number of leaves, concentration of chlorophyll, percentage of nitrogen, phosphorous, silicon, root yield, leaf yield, Percentage of dry matter, T.S.S, Whereas, the treatment with cow manure overlapping with silicon was superior in the percentage of potassium, phenols and sugars, as it gave 4.11% 0.13 and 665% respectively, The treatment of the Vermicompost with calcium spray was characterized in the percentage of calcium as it gave 1.65%.

Exogenous calcium improves growth and physiological responses of pistachio rootstocks against excess boron under salinity

Although boron (B) is necessary for plant growth and development, excessive concentrations of it can be harmful. Toxicity due to boron can occur naturally in the soils of arid and semiarid areas. Soluble forms of Ca were applied as foliar sprays at 1.1 and 2.2 g L−1 on three pistachio rootstocks, namely Pistacia vera L. ‘Ghazvini’, P. vera L. ‘Badami-Riz’ and P. atlantica subsp. Atlantica. Effects of the foliar sprays were assessed on growth and physiological responses of the three rootstocks while an excess of B was added to the irrigation water under saline soil (ECe ≅12 dS/m). Four-month plants were irrigated with water containing B as boric acid (20 and 40 mg L−1). Calcium treatments occurred either as aminochelate or chloride, and were sprayed on the foliage once a week. The experiment lasted for 12 wk and terminated when 50% of the plants showed symptoms of B toxicity. Excess B retarded growth and affected physiological parameters including plant height, leaf number, leaf area, leaf dry weight, stem diameter, shoot dry weight, root length, root dry weight, leaf proline content, SPAD value and RWC. Boron concentrations increased in the plant tissues, due to the boric acid in the irrigation water, while foliar sprays of calcium reduced B content in the leaves, stems and roots. Applications of Ca-Chelate and CaCl2 (2.2 g L−1 each) significantly improved growth and physiological responses of all rootstocks. The Ca-Chelate was more effective than CaCl2 in ameliorating B toxicity. In terms of rootstock tolerance to B toxicity, ‘Ghazvini’ and ‘Atlantica’ were more tolerant than ‘Badami’. The results indicate that foliar sprays of Ca are effective in mitigating excess boron symptoms in pistachio rootstocks grown under saline conditions.

Evaluation of Calcium Sources for the Management of Botrytis Blight on Petunia Flowers

Previous studies have demonstrated the efficacy of calcium (Ca) spray applications derived from Ca chloride for reducing botrytis (Botrytis cinerea) infection severity on petunia (Petunia ×hybrida) flowers. This study examines the effects of six Ca sources for their efficacy in reducing Botrytis blight on petunia flowers and their potential to cause spray damage or phytotoxicity. In the first experiment, the six Ca sources evaluated were laboratory-grade and commercial-grade Ca chloride, Ca nitrate, Ca ethylenediaminetetraacetic acid chelate, Ca amino acid chelate, and Ca silicate. In the second experiment, petunia flowers that were 0, 1, 3, 5, or 7 days old at the time of the Ca spray applications were evaluated for spray damage severity. For both experiments, treatments were applied to flowering plants. For the evaluation of Botrytis blight efficacy, flowers were excised and inoculated with botrytis spores 24 hours after the Ca spray application, and were evaluated every 12 hours for 72 hours. Laboratory-grade and commercial-grade Ca chloride at 1250 mg⋅L–1 Ca were the most effective Ca sources evaluated for decreasing Botrytis blight severity while not causing spray damage at any flower age. Spray damage to the flowers from the Ca chloride application increased when Ca concentrations increased to 2000 mg⋅L–1, but no additional benefit was observed for reducing Botrytis blight severity compared with the 1250-mg⋅L–1 Ca application. The results demonstrate that several Ca sources reduce Botrytis blight severity significantly; however, selection of the Ca source is important for minimizing the risk of spray damage.

Effect of Foliar Application of Calcium and Nano-Chitosan on the Growth of Rose Seedlings

During 2021-2022 growing season atAl-Rafidain private nursery in Zayouna, Baghdad, researchers examined the impact of spraying calciumand nano-chitosan on the development, flowering, and storability of the rose variety Anglina. The experiment was set up as a factorial experiment with three replicates, testing foliar sprays of calcium at concentrations of 0, 150, and 200 mg. L-1 and nano-chitosan at concentrations of 0, 50, 100, and 150mg.Liter-1. In particular, the number of leaves per plant increased to 75.70, the chlorophyll content increased to167.3 mg 100g -1 fresh weight, the dry matter percentage in the leaves increased to 41.45%, the total carbohydrate content in the leaves increased to 20,093 mg 100 g -1 fresh weight, the percentage of calcium in the leaves increased to1.108, and the vase life of the stored flowers increased to w days. When compared to the control treatment, which resulted in the lowest averages for the aforementioned traits, foliar spraying of nano-chitosan at a concentration of150 mg.l-1 resulted in superior vegetative and floral characteristics, including an increase in leaf number (66.70 leaves), leaf total carbohydrates (17.567% mg.100 g-1. Fresh weight), leaf percentage of calcium (1.1121%), and vase life after storage (8.18) days.

Effects of preharvest sprays of iodine, selenium and calcium on apple biofortification and their quality and storability.

The low dietary intake of iodine (I) and selenium (Se) by humans leads to serious health and socioeconomic problems. Therefore, enrichment of plants with I and Se using fertilisers containing these micronutrients is commonly recommended. In this study, we examined the impacts of combined spraying of I as iodide or iodate, Se as selenite or selenate, and calcium (Ca) as Ca-chloride on the enrichment of 'Red Jonaprince' (Malus domestica Borth.) apples, as well as fruit quality and their storability. Sprays were applied 2 weeks before harvest at rates of 0.5 kg I, 0.25 kg Se and 7 kg Ca per ha. Trees not sprayed with these nutrients served as controls. The tested sprays caused leaf burn, but they did not affect the cold injury of buds and shoots. Those sprays had no effect on yield, fruit size and russeting or skin colouring. At harvest, sprayed apples contained about 50 times more I and Se and 30% more Ca than the control fruit. After storage, compared to the control fruit, sprayed apples were firmer, had more organic acids and were less susceptible to disorders, such as bitter pit, internal breakdown and decay caused by Neofabraea spp. The results indicate that preharvest spraying with I, Se and Ca at high rates can be recommended to effectively enrich apples with I and Se and to simultaneously improve their storability.

Effects of prohexadione calcium spraying during the booting stage on panicle traits, yield, and related physiological characteristics of rice under salt stress.

Prohexadione calcium (Pro-Ca), as a growth retardant, can effectively alleviate the damage of salt stress to plants. In order to explore the effects of NaCl stress on the physiological characteristics and panicle traits of rice plants as well as the alleviating effect of Pro-Ca at the booting stage, we performed pot experiments on two rice cultivars: conventional rice 'Huanghuazhan' and hybrid rice 'Xiangliangyou900'. Rice plants were treated with 0.3% NaCl 48 hours after Pro-Ca (100 mg L-1) treatment to study the effects of Pro-Ca on the physiological characteristics of the leaves and panicles, as well as the panicle and yield traits of rice under salt stress. Our analysis indicated that NaCl treatment inhibited the morphological growth parameters and photosynthetic efficiency, destroyed the antioxidant defense systems of leaves and panicles, increased soluble protein and proline in both rice cultivars. Foliar application of Pro-Ca significantly increased the leaf area, uppermost internode length, panicle length, panicle weight, number of primary branches, number of grains per panicle, seed setting rate and yield under salt stress. Pro-Ca application significantly affected chlorophyll content, net photosynthetic rate (Pn), stomatal conductance (Gs), transpiration rate (Tr), and apparent mesophyll conductance (AMC) in NaCl-treated rice cultivars compared with NaCl treatment alone. Moreover, Pro-Ca also increased ascorbic acid (AsA) content, enhanced superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX) activity, and further increased the accumulation of soluble protein and proline in leaves and panicles. These results illustrated that foliar application of Pro-Ca at the booting stage could alleviate the damage caused by NaCl stress by regulating the physiological and metabolic processes of rice plants, thereby enhancing the stress resistance of the plants, increasing total rice yield in salt stress conditions.

Effect of pre-harvest spray of PGRs, calcium and cow urine on yield and quality of aonla fruit (Emblica officinalis Gaertn.)

Aonla or Indian gooseberry is an indigenous fruit to Indian subcontinents, which is regarded as amritphal. It is cultivated in India in 95000 ha area out of which more than 70% area is covered by cultivar NA-7. In north India, 30-80 percent of fruits are affected by brown spots. Such type of affected fruits has poor marketability and is not very suitable for processing purposes. Therefore, an investigation was carried out on the effect of the pre-harvest spray of PGRs, calcium, and cow urine. The experiment was laid out in a randomized block design (RBD) with three replications and nine treatments i.e., T1- control, T2- Salicylic Acid @ 2 mmol + Mulch, T3- Calcium Nitrate (CN) @1? + Mulch, T4- Benzyl Adenine (BA) @75 ppm+ Mulch, T5- Salicylic acid @2 mmol + BA (Benzyl Adenine) @75ppm + Mulch, T6- Salicylic acid @2 mmol + Calcium nitrate @1? + Mulch, T7- Calcium nitrate @1? + BA (Benzyl Adenine) @75ppm + Mulch, T8- Cow Urine @35? + Mulch, T9- Mulch on aonla fruit at the Main Horticulture Experiment Station, A.N.D.U.A and T, Kumarganj, Ayodhya during the year 2021-22. These treatments were sprayed twice on the aonla tree, in order to standardize the best pre-harvest treatment for improving the yield and quality of aonla fruits. Maximum fruits length (3.64cm), width (3.58cm), fruit weight (33.32g), fruit volume (30.23cm3), stone weight (2.18g), stone pulp ratios (14.62), fruit firmness (12.75 kg/cm3), yield (34.96 kg/tree), T.S.S. (10.33Brix0), total sugars (7.89%), reducing sugar (4.19%) and non-reducing sugars (3.70%), ascorbic acid (477mg/100g) and minimum blemished fruit (13%), and acidity (1.85%) were found with the treatment T8- Cow urine + mulch followed by T5- Salicylic acid + benzyl adenine + mulch.