Effect of foliar application of nutrients on growth and yield of zucchini (Cucurbita pepo L.)

Introduction

Zucchini (Cucurbita pepo L.), commonly known as summer squash, is an important vegetable crop belonging to the family Cucurbitaceae and is native to tropical America. It is a fast-growing, early-yielding crop valued for its high nutritional and economic importance. The fruits are low in calories and fat but are rich in vitamins, minerals, dietary fiber, phenolic compounds, flavonoids, and antioxidants, making Them beneficial for human health (Tamer et al., 2010) [1] . Zucchini grows best under cool and humid climatic conditions with an optimum temperature range of 16-27 °C. The crop is widely cultivated in several parts of India, including Punjab, Uttar Pradesh, Haryana, Himachal Pradesh, Jammu and Kashmir and West Bengal (Thamburaj and Singh, 2001; Dhaliwal, 2012; Pandey et al., 2018) [2,3,4] . The productivity and quality of zucchini are greatly influenced by balanced nutrient management. Foliar fertilization has become an effective method of supplying nutrients directly to plant foliage, ensuring rapid absorption and efficient utilization compared with soil application. The effectiveness of foliar nutrient application depends on several factors, including The nutrient solution, environmental conditions, and plant characteristics (Shahid et al. 2017; Kah et al. 2019) [5,6] . Foliar application is particularly beneficial under conditions where soil nutrient availability is restricted and has been reported to improve plant growth, flowering, fruiting, and yield in many vegetable crops (Begum and Fry, 2022; Narimani et al. 2010; El-Fouly et al. 2011; Abdoli. 2020) [7,8,9,10,11] . Previous studies have demonstrated that fertilization significantly influences nutrient uptake, vegetative growth, and yield in zucchini (Martinetti and Paganini, 2006) [12] . Nitrogen fertilization, either alone or combined with foliar nutrient application, has been reported to enhance vegetative biomass and productivity (Doikova et al., 1996) [13] . Although foliar nutrition has shown promising results in several vegetable crops (Panayotov. 2005; Panayotov and Stoeva, 2005; Fernandez et al. 2013) [14] , limited information is available regarding the comparative performance of different foliar nutrient sources in zucchini. Therefore, the present investigation was undertaken to evaluate The effect of foliar application of nutrients on The growth and yield of zucchini (Cucurbita pepo L.).

Materials and Methods

The present investigation entitled "Effect of Foliar Application of Nutrients on Growth and Yield of Zucchini (Cucurbita pepo L.)" was conducted during The Rabi season (January-May 2025) at The Regional Wheat Rust Research Station, Mahabaleshwar, Satara, Maharashtra, India (17° 93′N latitude and 73° 61′ E longitude), situated at an altitude of 1270 m above mean sea level. The experimental site falls under a high rainfall zone with red soil susceptible to leaching. The soil had a pH of 6.7, EC of 0.2 dS m ¹, available nitrogen of 192 kg ha ¹, available phosphorus⁻ ⁻ (P₂O₅) of 61.82 kg ha⁻¹, available potassium (K₂O) of 121 kg ha⁻¹, and adequate micronutrient status. The experiment was laid out in a Randomized Block Design (RBD) with seven treatments and three replications as represented in Table 1. The field was prepared by ploughing followed by cross cultivation and levelling to obtain a fine tilth. The crop was sown on ridges and furrows at a spacing of 60×60 cm with a plot size of 3.6×3.6m². A recommended fertilizer dose of 125:62.5:62.5 kg N: P₂O₅: K₂O ha ¹ ⁻ was uniformly applied to all treatments, and standard agronomic practices were followed throughout The crop growth period. Foliar application of different nutrient sources was carried out at 0.5% concentration at 30 days after sowing (DAS) and 1.0% concentration at 60 DAS. Observations on growth, flowering and yield parameters were recorded following standard procedures. The experimental data were statistically analysed by The analysis of variance (ANOVA) for Randomized Block Design as described by Panse and Sukhatme (1985) [15] .

Result and Discussion

The data pertaining to plant height at 30, 60, 90 DAS and at last harvest as influenced by foliar application of nutrients are presented in Table 2 and illustrated in Fig. (a). Plant height did not differ significantly among the treatments at 30 DAS with values ranging from (5.07 to 7.11 cm). However, significant differences were observed at 60 DAS. Among The treatments, T₆ (19:19:19) recorded the highest plant height (25.90 cm), which was statistically at par with T₂ (Phule Micrograde-II) (24.89 cm) and T₃ (Calcium nitrate) (24.67 cm). The lowest plant height was recorded in T₁ (Control) (19.02 cm). At 90 DAS and at the last harvest, the differences among treatments were non-significant. The increase in plant height under T₆ (19:19:19) may be attributed to the balanced supply of nitrogen, phosphorus and potassium, which enhanced nutrient uptake, chlorophyll formation, photosyn Thesis and cell elongation, thereby promoting vigorous vegetative growth. Similar findings were reported by Maurya et al. (2024) [16] , Nongmai Them et al. (2023) [17] who observed significant improvement in plant height following foliar application of balanced nutrients in cucurbit crops.

The data pertaining to East-West plant spread at 30, 60, 90 DAS and at last harvest are presented in Table 2 [16] and Nongmaithem et al. (2023) [17] in zucchini and cucumber

The data pertaining to North-South plant spread at 30, 60, 90 DAS and at last harvest are presented in Table 3. The observations on North-South plant spread revealed nonsignificant differences at 30 DAS. However, significant variation among treatments was recorded at 60 DAS, 90 DAS and at The last harvest. The highest plant spread was recorded in T₆ ( [17] in zucchini.

The data regarding petiole length are presented in Table 3. Foliar application of nutrients significantly influenced petiole length. The maximum petiole length (28.28 cm) was recorded in T₆ (19:19:19), which was statistically at par with T₂ (Phule Micrograde-II) (26.73 cm), T₃ (Calcium nitrate) (25.48 cm) and T₇ (12:61:00) (25.21 cm). The minimum petiole length (18.70 cm) was observed in T₁ (Control). The increase in petiole length may be attributed to The role of macro-and micronutrients in cell division, protein syn Thesis, chloroplast development, auxin syn Thesis, vascular tissue differentiation and photosynthesis, which collectively promoted vigorous vegetative growth. Similar results were reported by Monika et al. (2023) [18] in Cucurbita pepo var. styriaca.

Flower observations Days for initiation of first male flower

The data pertaining to the number of days required for initiation of the first male flower as influenced by foliar application of nutrients are presented in Table 4. The results revealed that the treatments did not differ significantly with respect to the initiation of the first male flower. The number of days required for first male flower initiation ranged from 22.40 to 23.20 days.

The nonsignificant variation among treatments may be attributed to the fact that foliar nutrient sprays were applied at 30 DAS, whereas initiation of the first male flower had already occurred before The application of treatments. Therefore, this character was mainly governed by the genetic makeup of the cultivar and prevailing environmental conditions rather than nutrient application. Similar observations were reported by Whitaker and Davis. (1962) [19] ; Robinson and Decker-Walters. (1997) [20] in cucurbit crops.

Days for initiation of first female flower

The data regarding the number of days required for initiation of the first female flower are presented in Table 4. Foliar application of nutrients did not exert a significant influence on this character. The initiation of the first female flower varied from 41.53 to 43.53 days after sowing. The absence of significant differences among treatments indicates that flowering behaviour and sex expression in zucchini are largely controlled by genetic and environmental factors. Although foliar nutrient application improved vegetative growth, it did not substantially influence The initiation of The first female flower. Similar findings were reported by Whitaker and Davis (1962) [19] ; Robinson and Decker-Walters. (1997) [20] in cucurbitaceous vegetables

Number of days required from opening of female flower to harvesting of Zucchini

The data pertaining to The number of days required from opening of The female flower to harvesting are presented in [21] in bottle gourd and Maurya et al. (2024) [16] in zucchini. [22] , Hazra et al.

(1987) [23] , Monika et al. (2023) [18] and Sidhu et al. (2020) [24] .

Days last harvest

The data regarding days to last harvest are presented in Table 5 [25] , Yadav et al. (2020) [26] and Narayanamma et al. (2009) [27] .

The data pertaining to harvesting duration are presented in [24] , Yadav et al. (2020) [26] and Narayanamma et al. (2009) [27] .

Number of pickings

The data pertaining to the number of pickings are presented in (2024) [16] and Patil et al. (1996) [21] .

Number of fruits per plant

The data pertaining to the number of fruits per plant are presented in Table 5 [16] , Nongmaithem et al. (2023) [17] , Sidhu et al. (2020) [24] , Singh et al. (2023) [25] and Monika et al. (2023) [18]

The data pertaining to fruit length as influenced by foliar application of nutrients are presented in Table 6. The results revealed significant differences among the treatments. The maximum fruit length (24.40 [16] , Kumar et al. (2020) [28] , Yadav et al.

(2020) [26] , Salama et al. (2019) [29] and Singh et al. (2023) [25] .

The data pertaining to fruit diameter are presented in Table 6 [16] , Dominy (2010) [30] , Marschner et al. (1990) [31] and El-Shoura (2020) [11] .

The data regarding average fruit weight are presented in Table 6 and illustrated in Fig( b). Significant differences among The treatments were observed. The highest fruit weight (215 g) was recorded in T₆ (19:19:19), which was statistically at par with T₃ (Calcium nitrate) (214 g), T₂ (Phule Micrograde-II) (212 g) and T₅ (Zinc sulphate) (207 g). The lowest fruit weight (156 g) was recorded in T₁ (Control). The increase in fruit weight under balanced nutrient application may be attributed to enhanced photosynthesis, improved carbohydrate accumulation, better nutrient translocation and vigorous vegetative growth, resulting in improved fruit development. Similar findings were reported by El-Shoura (2020) [11] , Salama et al. (2019) [29] , Sidhu et al.

(2020) [24] , Singh et al. (2023) [25] and Monika et al. (2023) [18] .

The data pertaining to fruit yield per plant are presented in [16] , Singh et al. (2023) [25] , Salama et al. (2019) [29] , Nongmaithem et al. (2023) [17] and Sidhu et al. (2020) [24] .

The data regarding yield per plot are presented in (2024) [16] , Salama et al. (2019) [29] , Monika et al. (2023) [18] and Shafique et al. (2022) [32] .

Yield per hectare (t)

The data pertaining to yield per hectare are presented in (2024) [16] .

Conclusion

The study concluded that foliar application of nutrients significantly improved the growth, yield, fruit quality, and nutrient status of zucchini. NPK 19:19:19 proved to be the most effective treatment, producing superior vegetative growth, higher yield, and better fruit quality. Calcium nitrate and Phule Micrograde-II also showed beneficial effects but were less effective than NPK 19:19:19. Therefore, foliar application of NPK 19:19:19 is recommended for enhancing zucchini productivity under Mahabaleshwar agro-climatic conditions.

Acknowledgement

AcknowledgementsThe authors gratefully acknowledge the support of staff from RCSM Govt. College of Agriculture, Kolhapur and staffs of RWRRS, Mahabaleshwar for Their invaluable contributions to this research.

References

1. Tamer CE, Incedayi B, Parseker AS, Yonak S, Copur OU. Evaluation of several qualitv criteria of low-calorie pumpkin dessert. Not Bot HortiAgrobot Cluj. 2010;38:7680.
2. Thamburaj S, Singh N. Textbook of vegetables, Tuber crops and Spices. Indian Council of Agricultural Research, New Delhi; 2001:286.
3. Dhaliwal MS. Handbook of Vegetable Crops. 2nd revised edition. New Delhi: Kalyani Publishers; 2012:116-117.
4. Pandey BK, Maurya SK, Bhat LL, Pooja, Chauhan DS. Performance of Summer Squash (Cucurbita pepo L.) under Protected Conditions in Terai Region Uttrakhand. Field Crop. 2018;1.
5. Shahid M, Dumat C, Khalid S, Schreck E, Xiong T, Niazi NK. Foliar heavy metal uptake, toxicity and detoxification in plants: A comparison of foliar and root metal uptake. Journal of Hazardous Materials. 2017;325:36-58.
6. Kah M, Tufenkji N, White JC. Nano-enabled strategies to enhance crop nutrition and protection. Nature Nanotechnology. 2019;14(6):532-540.
7. Begum RA, Fry SC. Boron bridging of rhamnogalacturonan-II in Rosa and Arabidopsis cell cultures occurs mainly in The endo-membrane system and continues at a reduced rate after secretion. Annals of Botany. 2022;130(5):703-715.
8. Narimani H, Rahimi MM, Ahmadikhah A, Vaezi B. Study on The effects of foliar spray of micronutrient on yield and yield components of durum wheat. Arch.Appl. Sci. Res. 2010;2:168-76.
9. El-Fouly MM, Mobarak ZM, Salama ZA. Micronutrients (Fe, Mn, Zn) foliar spray for increasing salinity tolerance in wheat Triticum aestivum L. Afr. J. Plant Sci. 2011;5:31422.
10. Abdoli M. Effects of micronutrient fertilization on The overall quality of crops. In Plant Micronutrients, Springer, Cham. 2020:31-37.
11. EI-Shoura AM. Effect of foliar application with some treatments on summer squash Middle East Journal of Agriculture Research. 2020;9:468-478.
12. Martinetti L, Paganini F. Effect of organic and mineral fertilization on yield and quality of zucchini. Acta Horticulture. 2006.
13. Doikova M, Belichki I, Boteva HR. Biological removal of N, P₂ 0 ₅ and K₂ 0 with vegetable marrow yield under conditions of mineral fertilizer application, Proceedings of The First Balkan Symposium on Vegetables and Potatoes, Belgrade, Yugoslavia 4-7 Yuly, vol. Il Acta Hort 462. 1996:801-808.
14. Panayotov N, Stoeva N. Physiological status of pepper after application of leaf fertilizers Masterbland. Scientific works of Agricultural University, Plovdiv. 2005;50:65-70.
15. Panse VG, Sukhatme PV. Statistical methods for agricultural workers. 4th ed ICAR, New Delhi. 1985;361.
16. Maurya S, Singh RB, Rajiv, Singh D, Nirankar, Anoop KG, Sanjay V, Devendra M. 2024.
17. NongmaiThem et al. Impact of micronutrient foliar application on Cucurbita pepo on growth yield. The Pharma Innovation Journal. 2023;12(4):1789-1792.
18. Monika, Dhatt AS, Sharma M, Meena OP, Ram H, Singh Khosa J, Sidhu MK. Optimization of yield and quality of hull-less seeded pumpkin (Cucurbita pepo var. styriaca) through foliar application. Vegetable Science. 2023;50(1):58-64.
19. Whitaker TW, Davis GN. Cucurbits: Botany, Cultivation and Utilization. Interscience Publishers, New York; 1962.
20. Robinson RW, Decker-Walters DS. Cucurbits. CAB International, Wallingford, UK. 1997.
21. Patil SR, Desai UL, Pawar BG, Patil BT. Effect of NPK doses on growth and yield of bottle gourd cv. Samrat. Journal of Maharashtra Agricultural Universities. 1996;21(1):65-67.
22. Hatwar GP, Gondane SV, Urkude SM, Gahukar OV. Effect of micronutrients on growth and yield of chilli. Soil and Crop. 2003;13:123-25.
23. Hazra P, Maitry TK, Mandal AR. Effect of foliar application of micronutrients on growth and yield of okra (Abelomoschus esculentus L.) Prog. Hort. 1987;19:219222.
24. Sidhu MK, Harish CR, Sandeep KR, Lila Bora, Shukla YR. Effect of foliar application of boron, iron and zine on growth, yield and economics of cucumber grown under naturally ventilated polyhouse condition. Vegetable Science. 2020;47(1):110-115.
25. Singh A, Singh DP, Neha, Singh S. Influence of foliar feeding of N.P.K. (19:19:19) on growth, yield and quality of cucumber (Cucumis sativus L.) cv. Pusa Seedless Cucumber-6 under net house. International Journal of Current Microbiology and Applied Sciences. 2023;12(8):3037.https://doi.org/10.20546/ijcmas.2023.1208.005
26. Yadav RK, Sekhar M, Khan W, Madhu M. Impact of foliar application of micronutrients on growth, yield and its attributes of bitter gourd (Momordica charantia L.) cv. F LHB-₁ Swathi. International Journal of Chemical Studies. 2020;8(4):1344-1349.
27. Narayanamma M, Radha RK, Kameswari LP, Reddy RVSK. Effect of foliar application of micronutrients on yield components, yield and nutrient content of bitter gourd (Momordica charantia L.). The Orissa Journal of Horticulture. 2009;37(2):78-81.
28. Kumar R, Singh M. Effect of foliar application of boron, iron, and zinc on growth, yield, and quality of cucumber (Cucumis sativus L.). Veg Sci. 2020;47(1):110-114.
29. Salama AR, Fekry WA, Wahdan HM. Influence of some squash cultivars and growth stimulants on flowering, yield and fruit quality at autumn-winter season under open field conditions. Journal of Productivity and Development. 2019;24(3):433-460.
30. Dominy AP. Studies of The micronutrients zinc, manganese, and silicon in cucumbers (Cucumis sativus). [dissertation]. Pietermaritzburg: University of KwaZuluNatal; 2010.
31. Marschner H, Oberle H, Cakmak I, Romheld V. Growth enhancement by silicon in cucumber (Cucumis sativus) plants depends on imbalance in phosphorus and zinc supply. Plant Soil. 1990;124(2):211-219.
32. Shafique BS, Rayhan A, Kawsar H, Akhinur S, Kazi IA, Sabia khan, Mohammed M. Foliar fertilization of micronutrients on The performance of zucchini squash (Cucurbita pepo) under The Old Meghna Estuarine Floodplain of Bangladesh. Department of Agriculture, Faculty of Science Noakhali Science and Technology University, Noakhali, Bangladesh. 2022;23(2):380-392.
33. Fernandez V, Eichert T. Uptake of hydrophilic solutes through plant leaves: current state of knowledge and perspectives of foliar fertilization. Critical Reviews in Plant Sciences. 2009:36-68.