Effect of pelleted vermicompost on quality and nutrient content of organic greengram (Vigna radiata L.)

Introduction

Greengram (Vigna radiata L.) is an important pulse crop widely cultivated in India and serves as a major source of dietary protein (Kumar and Ali, 2004) [1] . Improving the nutritional quality of pulses is essential for addressing malnutrition and ensuring food security. Globally, organic farming is practiced on about 76 million hectares of land (FiBL, 2021) [4] , while in India about 9.11 million hectares are under organic cultivation (APEDA, 2023) [3] . Under organic farming systems, nutrient availability plays a crucial role not only in yield but also in determining the quality and nutrient composition of produce. Organic manures such as vermicompost are known to enhance soil fertility, microbial activity and nutrient availability. Pelleted vermicompost offers additional advantages such as ease of application, improved nutrient use efficiency and slow release of nutrients. However, limited information is available on the effect of pelleted vermicompost and its scheduling on quality and nutrient composition of greengram. Therefore, the present investigation was undertaken.

Materials and Methods

The experiment was conducted during kharif 2022 at the Organic Farming Unit, Rajasthan College of Agriculture, MPUAT, Udaipur. The soil of the experimental site was typical of the region and the climate was sub-humid. The experiment was laid out in factorial randomized block design (FRBD) with three replications, comprising 15 treatment combinations involving four levels of pelleted vermicompost (1, 2, 3 and 4 t ha⁻¹) along with control, and three scheduling treatments. The treatment combinations were randomized with the help of random number table (Fisher, 1950) [5] Greengram variety GM-4 was sown at spacing of 30 cm × 10 cm using seed rate of 15 kg ha⁻¹.

Preparation of vermicompost pellets

Well dried vermicompost is taken after proper sieving into a container and bentonite as binding agent, is thoroughly mixed and then taken into the pellet making machine which makes small cylindrical pellets. The cylindrical pellets are than placed in centrifugal machine which helps in transforming the cylindrical pellets into spherical pellets.

Quality analysis

 Protein content was determined by multiplying nitrogen content with factor 6.25 (Lowry et al., 1951) [8]  Carbohydrate content was estimated by Anthrone method (Sadasivam and Manickam, 2008) [11]  Fat content was determined by AOAC (2005) [2] method using Soxhlet apparatus.

Nutrient analysis

Plant samples were analyzed for N, P, K, Zn and Fe using standard laboratory procedures Colorimetric method by Snell and Snell (1949) [12] , Ammonium vanado-molybdate yellow colour method by Richards (1968) [10] , Flame Photometer method by Jackson (1973) [6] , Estimation on AAS by Lindsay and Norvell (1978) [7] , respectively. Statistical analysis of the individual data of various characters studied in the experiment will be carried out as per Factorial Randomized Block Design (FRBD) as suggested by Panse and Sukhatme (1985) [9] .

Results and Discussion

Quality Parameters Protein Content

Protein content in seed was significantly influenced by pelleted vermicompost. The highest protein content (24.97%) was recorded under 4 t ha⁻¹, which was significantly superior to all other treatments. Among scheduling treatments, split application (S₃) recorded significantly higher protein content (24.01%) compared to S₂ and S₁.

The increase in protein content may be attributed to enhanced nitrogen availability and uptake, which promotes protein synthesis in plants.

Carbohydrate and Fat Content

Carbohydrate and fat content were not significantly influenced by doses and scheduling of pelleted vermicompost. This indicates that these parameters are relatively stable and less responsive to nutrient management.

Nutrient Content in Seed Nitrogen Content

Nitrogen content in seed increased significantly with increasing dose of pelleted vermicompost, with maximum value (3.99%) recorded under 4 t ha⁻¹. Split application (S₃) also recorded significantly higher nitrogen content compared to S₂ and S₁.

Phosphorus Content

Phosphorus content was significantly higher under 4 t ha⁻¹ (0.56%) compared to lower doses. Scheduling treatment S₃ recorded significantly higher phosphorus content, indicating better nutrient availability.

Potassium Content

Potassium content in seed increased significantly with increasing dose, with highest value (1.39%) recorded under 4 t ha⁻¹. Split application also resulted in higher potassium content.

Zinc and Iron Content

Zinc and iron content were significantly higher under 4 t ha⁻¹ pelleted vermicompost and S₃ scheduling. This may be due to enhanced microbial activity and improved nutrient solubilization.

Nutrient Content in Haulm

Nitrogen, phosphorus, potassium, zinc and iron content in haulm were significantly higher under 4 t ha⁻¹ pelleted vermicompost and split application. Improvement in nutrient content may be attributed to better nutrient uptake and translocation under improved soil conditions.

Acknowledgement

AcknowledgmentWe are intensely thankful to the Department of Agronomy, Rajasthan College of Agriculture, MPUAT, Udaipur for providing us facilities for quality analysis of greengram.

References

1. Ali M, Kumar S. Prospects of mungbean in rice-wheat cropping systems in Indo-Gangetic Plains of India. In: Improving income and nutrition by incorporating mungbean in the cereal fallows of the Indo-Gangetic Plains of South Asia. 2004. p. 246-254.
2. AOAC. Official methods of analysis. 11th ed. Washington (DC): Association of Official Agricultural Chemists; 1960. p. 174.
3. APEDA. Organic products [Internet]. Agricultural and Processed Food Products Export Development Authority; 2023 [cited 2023 Apr 26]. Available from: http://apeda.gov.in/apedawebsite/organic/Organuic_Pro ducts.htm
4. FiBL, IFOAM. The world of organic agriculture: Statistics and emerging trends. 2021. p. 1-136.
5. Fisher RA. Statistical methods for research workers. Edinburgh: Oliver and Boyd; 1950.
6. Jackson ML. Soil chemical analysis. Englewood Cliffs (NJ): Prentice Hall Inc.; 1973.
7. Lindsay WL, Norvell WL. Development of a DTPA soil test for Zn, Fe, Mn and Cu. Soil Science Society of America Journal. 1978;42:421-442.
8. Lowery GH, Newman RJ. Notes on the ornithology of southeastern San Luis Potosi. The Wilson Bulletin. 1951;63(4):315-322.
9. Panse VG, Sukhatme VP. Statistical methods for agricultural workers. New Delhi: Indian Council of Agricultural Research; 1985.
10. Richards LA. Diagnosis and improvement of saline and alkali soils. USDA Handbook 60. New Delhi: Oxford and IBH Publishing Co.; 1968.
11. Sadasivam S, Manickam A. Biochemical methods for agricultural sciences. 6th ed. New Delhi: New Age International (P) Ltd.; 2008.
12. Snell PD, Snell GT. Colorimetric methods of analysis. 3rd ed. Vol. 2. New York: Van Nostrand Co. Inc.; 1949.