Effect of chemical fertilizer application in split on yield of hybrid coconut cv. TXD (Mahuva)

Introduction

The coconut palm (Cocos nucifera L.) belongs to the palm family (Arecaceae) is the most useful palm in the world. Every part of the tree is useful to human life for some purpose or the other. Hence, the coconut palm is endearingly called 'Kalpa vriksha' meaning the tree of heaven. The copra obtained by drying the kernel of coconut is the richest sources of vegetable oil containing 65 to 70 per cent oil. The coconut palm is suitable to grow under varying climatic and soil conditions. It is essentially a tropical plant growing mostly between 20° N and 20° S latitudes. However, a well distributed rainfall of about 2000 mm/year is ideal for proper growth and maximum production. Coconut is grown under different soil types such as loamy, laterite, coastal sandy, alluvial, clayey and reclaimed soils of the marshy low lands. The ideal soil conditions for better growth and performance of the palm are proper drainage, good water-holding capacity and presence of water table within 3 m and absence of rock or any hard substratum within 2 m of the surface. The coconut palm continues to yield more than over 80 years. Coconut is currently grown in more than 90 countries spread along the tropical belt of 12.26 million hectares (Anon., 2021) [2] in the world (Fig. 1.1), eight million hectares, or about 70% is in South East & East Asia (Carpio, et al., 2005) [4] . India occupied an area of 2.28 million hectares with an annual production of 20535.88 million nuts as per an estimate (All India final estimates) of 2022-23 (Anon., 2023). Cultivation of coconut in India is restricted to fifteen states/Union Territories and most of these are located on coastal belts or sea shore. Among the various states/Union Territories, Kerala and Karnataka ranks first and second in area respectively and Karnataka and Kerala ranks first and second in production respectively, whereas Gujarat stands at 8 th position in area (24,780 ha) and 7 th position in production (211.33 million nuts). In order to attain self-sufficiency for coconut and its byproduct, it is necessary to improve and increase the production. This can be achieved either by increasing the production per unit area or by increasing the existing area under coconut crop through new planting. The solution to the problem on a long-term basis lies in extending the area under coconut and also replacing the old and uneconomic trees in the existing gardens by planting vigorous seedlings of new improved cultivars of coconut (Kutty, 1955) [5] . Balanced nutrition is a pre-requisite for proper growth of plant, yield and quality of produce. This is indispensable especially in fruit and plantation crops like coconut as they are perennial in nature. Coconut is an important crop of coastal region of Saurashtra. Old information and recommendations on nutritional aspect for this were available for South Gujarat conditions but it was scanty especially for varieties released in Saurashtra region. Further it was also necessary to re-test the nutritional need of the plant in present conditions as many climatic changes has been taken place in last decades. Apart from this, meeting the crop needs at the same time as maintaining and improving native soil fertility and productivity of today's needs and is of great importance. Optimal and consistent fertilization significantly increases coconut yield, but the effect of a specific dose varies based on the tree's age, the method of application, soil conditions, and the nutrients included. There were very little findings available about the use of fertilizer application in more than 2 splits, especially in hybrid coconut variety TxD (Mahuva). Keeping these views in mind this research trial was carried out with the objective to find out optimum dose and split of chemical fertilizer for coconut cv. TxD (Mahuva).

Materials and Methods

The present trial was taken up at Agricultural Research Station (Fruit Crops), Junagadh Agricultural University, Mahuva, Dist. Bhavnagar, Gujarat, India during the year 2013-14 to 2016-17. The coconut variety under investigation was TxD (Mahuva) and with 25 years old palm were selected for the study. The experiment was set up using Randomized Block Design with a Factorial concept (FRBD), involving two factors and nine treatment combinations. The first factor as dose of fertilizers viz., D1: 100% RDF NPK @ 1500, 750, 1500 g/palm/year, D2: 125% RDF NPK @ 1875, 938, 1875 g/palm/year, D3: 150% RDF NPK @ 2250, 1125, 2250 g/palm/year and second factor as number of splits of fertilizers viz., S1: Two split [June-Oct. (Control)], S2: Three Split (June-Oct.-Feb.), S3: Four Split (June-Aug.-Nov.-Feb.). The different treatment combinations are as follow (1) D1S1 ( 2) D1S2 (3) D1S3 (4) D2S1 ( 5) D2S2 ( 6) D2S3 ( 7) D3S1 (8) D3S2 ( 9) D3S3. The uniform application of 50 kg FYM/palm/year followed in each treatment combination. The treatments replicated for three times. There were two palm taken per treatment. The all other cultural practices performed as per recommendation and requirements. Soil analysis was carried out before and at the end of the experiment to assess the fertility status of the soil. The observations related to nut yield and yield attributes like nut length, nut girth, and nut water content were noted every year for coconut fruits.

Results and Discussion

The outcomes of different treatments were documented and the results obtained during the investigation were thoroughly discussed, supported by reasoning and relevant references. The data recorded regarding nut yield and yield attributes are presented in Table 1 to Table 4. The results of different treatments on nut length of coconut cv. TxD (Mahuva) was presented in table 1. The results on nut girth presented in table 2 revealed that there is no any significant difference observed between treatments as well as treatment combinations in all the years as well as pooled analysis.

The results of different treatments on nut water content of coconut cv. TxD (Mahuva) was presented in table 3. The statistical analysis clearly indicated that with the fertilizer dose D3 (150% RDF NPK @ 2250, 1125, 2250 g/palm/year) the highest nut water content recorded in all the year as well as pooled data. And it was found at par with the fertilizer dose D2 (125% RDF NPK @ 1875, 938, 1875 g/palm/year) in all the years but not in pooled results. The similar results found in fertilizer application in split on nut water content during all the years and pooled data. The significantly higher nut water content observed in S3 (Four Split (June-Aug.-Nov.-Feb.)) and found at par with S2 (Three Split (June-Oct.-Feb.)) in all the years except pooled analysis. The results on interaction effect of DxS on nut water content revealed that the different treatments on nut water content was found significant during all years and pooled results. In the treatment combination D3S3 found the highest nut water content (162 ml) but it was found at par with D3S2 in pooled results. Solangi et al. (2014) also revealed that the quantity of nut water (188.77 ml) was significantly (p<0.05) high in T1 (Urea (N), Di-ammoniumphosphate (P), Murait ofpotash (K), (NPK) + Neem Seed Powder (NSP) + Gliricidia sepium leaves (GSL)) as compared to rest of the treatments. Kalpana et al. (2008) reported that the water content of coconut increased with the application of fertilizers. )) in all the years except pooled analysis. The results on interaction effect of DxS on nut yield revealed that the different treatments on nut yield was found significant during all years and pooled results. In the treatment combination D3S3 found the highest nut yield (13086) but it was found at par with D2S3 (13037) in pooled results.

The obtained results are in line with the findings of Anon. (2012) [1] in hybrid coconut varieties. In hybrid coconut varieties JVA1 and JVA2 the application of 110 kg N + 57 kg P2O5 + 140 kg K2O/ha/year, increased productivity to 155 fruits/tree/year and the oil content was as high as 68%.

According Long (2007) [6] application of fertilizers twice a year helped the tree grow, develop well and bear fruit early. Mohandas (2012) [7] concluded that for hybrid coconut, a fertilizer level of 1000:250:2000 g NPK/Palms/year along with 50 kg FYM was found to be economical for achieving higher nut yield and sustaining the soil fertility.

Coconut trees grow continuously and bear fruits all year round. Therefore, if fertilized many times a year, the tree will grow well, flower continuously increase the number of inflorescences and have high productivity. If divided and applied many times, the same amount of fertilizer will help trees absorb it more effectively and avoid losses (Tran and Nguyen, 2011) [9] . In particular, 4 times/year fertilized plots recorded high yields with a statistically significant difference as compared to 2 times/year fertilized (Nguyen et al., 2020) [8] .

Conclusion

As the coconut palm is perennial and producing nuts round the year. On the basis of the results obtained from the threeyear field experimentation, it seems quite logical to conclude that higher number of nut yield of hybrid coconut cv. TxD (Mahuva) can be secured by the application of FYM 50 kg/palm/year with 125% RDF NPK @ 1875, 938, 1875 g/palm/year or 150% RDF NPK @ 2250, 1125, 2250 g/palm/year with four equal split [June-Sept-Dec.-March].

References

1. Anonymous. Report on completion of the coconut sap variety database. Sci Technol Newsl. Research Institute for Oil and Oil Plants; 2012 [accessed 2025 Oct 09].
2. Anonymous. International Coconut Community (ICC) Statistical Year Book 2021. Jakarta (Indonesia): ICC; 2021.
3. Anonymous. All India Final Estimates of Area and Production of Horticulture Crops. Directorate of Economics and Statistics, Department of Agriculture and Farmers Welfare, Ministry of Agriculture and Farmers Welfare, Govt. of India; 2023.
4. Carpio CB, Santosh GA, Emmanue EE, Novarianto H. Research on coconut genetic resources in South and East Asia. In: Coconut Genetic Resources. Serdang (Malaysia): IPGRI-Regional Office for Asia, the Pacific and Oceania (IPGRI-APO); 2005. p. 533-545.
5. Kutty OVU. External characters of seed coconuts and the quality of seedlings. Indian Coconut J. 1955;8:7478.
6. Long VV. Research on applying multiplication techniques, seed storage and building a model of specialized coconut cultivation in Cau Ke district, Tra Vinh province: A scientific report summary. Research Institute for Oil and Oil Plants; 2007.
7. Mohandas S. Effect of NPK fertilizer levels on mineral nutrition and yield of hybrid (Tall × Dwarf) coconut. Madras Agric J. 2012;99(1-3):87-91.
8. Nguyen TDH, Le NC, Thai TNQ, Luu TQ, Nguyen CDX. Effects of phosphorus fertilizer on coconut growth, yield and quality at early reproductive stage under saline intrusion condition in Mekong Delta. J Agric Dev. 2020;19(4):18-27.
9. Tran HV, Nguyen LC. Investigating flowering characteristics of some tall coconut cultivars (Cocos nucifera L.) in Giong Trom district, Ben Tre province. Can Tho Univ J Sci. 2011;17(a):210-218.