Studies on effect of foliar application of water-soluble fertilizers on fruiting and yield parameters of mango (Mangifera indica L.) cv. Dashehari

Introduction

Mango (Mangifera indica L.) is one of the most important fruit crops cultivated commercially across tropical and subtropical regions worldwide. Belonging to the family Anacardiaceae. It originated in Southeast Asia. The genus Mangifera comprises 69 species (Kostermans and Bampard, 1993) [4] , though Mangifera indica accounts for nearly all edible varieties. In India, three species are found M. indica, M. sylvatica and M. coloneura. Mangoes have been cultivated for over 4,000 years, resulting in a wide array of cultivars with diverse flavours, shapes and sizes (De Candolle, 1904) [2] . Mango is a highly nutritious fruit, prized for its rich flavour and excellent taste. It serves as a valuable source of vitamin A (4,800 IU per 100 g) and vitamin C (13 mg per 100 g). One of the major factor contributing to low mango productivity is imbalanced fertilization. Research has shown that supplying nutrients through foliar feeding either as a substitute or a supplement to soil application significantly enhances fruit yield and quality (Samra et al., 1977) [6] . Foliar application of Nutrients is a common practice to address nutrient deficiencies and improve fruit quality. When applied directly to leaves these inputs have a significant positive effect on fruit set, yield and overall quality. They also aid in the recovery of trees facing nutritional or physiological stress (Singh et al., 2005) [8] . The principle behind foliar feeding is that nutrients are rapidly absorbed by the leaves and then distributed throughout the plant to meet its functional needs.

Materials and Methods

The experiment was conducted during the academic year 2025-26 at the Horticulture Farm, College of Agriculture, Indira Gandhi Krishi Vishwavidyalaya, Raipur (C.G.). The research trial was laid out in a Randomized Block Design (RBD) consist 9 different treatments i.e. T 0 = Control (water spray), T 1 = NPK (19:19:19) @ 1%, T 2 = NPK (19:19:19) @ 2%, T 3 = Mono Ammonium Phosphate (12:61:0) @ 1%, T 4 = Mono Ammonium Phosphate (12:61:0) @ 2%, T 5 = Potassium Nitrate (13:0:45) @ 1%, T 6 = Potassium Nitrate (13:0:45) @ 2%, T 7 = Urea Phosphate (17:44:0) @ 1%, T 8 = Urea Phosphate (17:44:0) @ 2% replicated thrice in 27 well developed mango tree having distance 10m. x 10m. All interculture operation and plant protection measures were applied uniformly to the entire experiment plot as per the practises for papaya cultivation. water-soluble fertilizers were applied on 8 January, 25 February and 24 March, between 7:00-12:00 noon. Sprays of varying concentrations were applied during the preflowering stage, pea and marble stages of fruit development.

The stock solution of NPK (19:19:19), Mono Ammonium Phosphate (12:61:0), Potassium Nitrate (13:0:45) and Urea Phosphate (17:44:0) was prepared by measure the weight of these fertilizer by weighing machine. These weighted sample was dissolved in water to makes up the required amount of solution. The plants were sprayed with the help of Foot sprayer with fine nozzle having mist droplets and the sprayer was washed thoroughly before spraying to avoid contamination. The observations were recorded on growth characters of mango viz. fruit length (cm), fruit diameter (cm), fruit volume (cm3), fruit specific gravity (g/cc), peel weight (g), pulp percent, stone weight and Pulp: stone ratio. The data were subjected to statistical analysis to test the level of significance as per method by Gomez and Gomez (1984) [3] .

Results and Discussion

Data in table 1 show that influence of Water-Soluble Fertilizers on fruiting and yield parameters of Mango.

Among the evaluated treatments, the highest Fruit length (11.46) was observed in T 6 , whereas T 0 exhibited the lowest Fruit length (8.11). It may be due to the increased rate of cell enlargement and the development of wider intercellular spaces during the later stages of fruit growth are primarily responsible for the elongation of fruit. In addition, nitrogen being a highly mobile macronutrient is readily translocated to developing fruits which act as strong nutrient sinks. This mobility supports various metabolic processes within the plant, further enhancing fruit elongation (Singh et al., 2005) [8] . Abd et al., 2022 [1] , reported similar observations, noting that the increase in fruit length may be attributed to the pivotal role of nitrogen in photosynthate assimilation and developmental processes.

Among the evaluated treatments, the highest fruit diameter (7.36) was observed in T 6 , whereas T 0 exhibited the lowest fruit diameter (4.72). The exogenous application of potassium fertilizer enhances photosynthetic assimilation, promotes cell expansion and facilitates the translocation of sugars to metabolic sinks such as developing fruits. Among potassium sources, foliar application of potassium nitrate (KNO₃) has been found to be particularly effective in increasing fruit diameter (Yeshitela et al., 2005) [9] .

Fruit volume (cm3)

The observation of data for fruit volume after spraying water-soluble fertilizers at different concentrations are illustrated in Table 1 in which the highest fruit volume (225.26) was observed in T 6 , whereas T 0 exhibited the lowest fruit volume (144.34). The observed increase in fruit volume may be attributed to the rapid translocation and accumulation of water and sugars resulting from the exogenous application of water-soluble fertilizers, particularly potassium-based formulations. Potassium contributes significantly by promoting the formation of larger intercellular spaces and regulating cellular water content, thereby enhancing fruit size and volume.

The result in table 1 show the effect of water-soluble fertilizers on specific gravity of fruit. Among the evaluated treatments, the highest specific gravity of fruit (1.08) was observed in T 0 , whereas T 6 exhibited the lowest specific gravity of fruit (1.01). Specific gravity is directly corelated with fruit weight and variation in fruit weight affect the specific gravity of fruit.

Pulp percentage

The application of different water-soluble fertilizers had significantly influenced the pulp percentage as compared to control. Among the evaluated treatments, the highest fruit pulp percent (72.62) was observed in T 6 , whereas T 0 exhibited the lowest fruit pulp percent (54.84). The increase in pulp weight can be attributed to potassium, which stimulates diverse enzymatic activities and promotes the accumulation of sugars in developing fruits. Additionally, nitrogen contributes by facilitating auxin synthesis in plants so overall the use of nitrogen provide plant a good amount of nitrogen and potassium which further enhancing pulp weight which are also responsible for overall enhancement of fruit pulp percent. (Meena et al., 2024) [5]

The obtained data in respect to weight of peel after spraying water-soluble fertilizers at different concentrations, the lowest peel weight (29.38) was observed in T 6 , whereas T 0 exhibited the highest peel weight (30.82).

The observation of data in respect to stone weight after spraying water-soluble fertilizers at different concentrations are illustrated in Table 1 in which the lowest stone weight (32.86) was observed in T 6 , whereas T 0 exhibited the highest stone weight (38.84).

Pulp: stone ratio

It is evident from the result obtained under present investigation the application of different water-soluble fertilizers had significantly influenced the pulp: stone ratio. Among the evaluated treatments, the highest pulp: stone ratio (5.05) was observed in T 6 , whereas T 0 exhibited the lowest pulp: stone ratio (2.16). The observed increase in the pulp: stone ratio may be attributed to the rapid translocation of metabolites and photosynthetic assimilates, synthesis of auxins, accumulation of sugars from source to sink (i.e., fruits), the efficient mobilization of nutrients and the enhanced rate of water absorption which was observed due to foliar feeding of nitrogen and potassium through application of potassium nitrate within the plant. These combined physiological processes contribute to a higher proportion of pulp relative to stone, thereby improving fruit quality. (Singh et al., 2005) [8] . The research findings are in confirmation with Sarkar are Rahim (2013) [7] .

References

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2. Candolle AD. Origin of cultivated plants. London: Vegal Paul Trench and Company; 1904. p.1-67.
3. Gomez KA, Gomez AA. Statistical procedures for agricultural research. 2nd ed. John Wiley & Sons; 1984. 680 p.
4. Kostermans AJGH, Bompard JM. The mangoes: their botany, nomenclature, horticulture and utilization. London: Academic Press Ltd; 1993. 233 p.
5. Meena MK, Kaushik RA, Sarolia DK, Singh V, Jain HK. Effect of different levels of micronutrients on vegetative growth, yield and fruit quality of mango (Mangifera indica L.). Journal of Agriculture and Ecology. 2024;19:97-102.
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7. Sarker BC, Rahim MA. Yield and quality of mango (Mangifera indica L.) as influenced by foliar application of potassium nitrate and urea. Bangladesh Journal of Agricultural Research. 2013;38(1):145-154.
8. Singh NP, Malhi CS, Sharma RC. Effect of foliar feeding of N, P and K on vegetative and fruiting characters of mango cv. Dashehari. In: Proceedings of the International Conference on Mango and Date Palm: Culture and Export. 2005;52(2):27-31.
9. Yeshitela T, Robbertse PJ, Stassen PJC. Potassium nitrate and urea sprays affect flowering and yields of Tommy Atkins (Mangifera indica L.) mango in Ethiopia. South African Journal of Plant and Soil. 2005;22(1):28-32.