Influence of foliar application of nutrients on nutrient content, nutrient uptake and post-harvest soil nutrient status of Horsegram [Macrotyloma uniflorum (Lam.) Verdc.] in Chhattisgarh plains

Introduction

Horsegram is a type of pulse that is also referred to as poor man's pulse crop and kulthi. The crop is a member of the Fabaceae family, a legume crop that is still underutilised. It is also known as Kurti-kalai (Bengali), Gahot (Kumaon and Garhwal), Ullavallu (Telgu), Muthira (Malyalam), Kollu (Tamil) and Kulattha (Sanskrit). As reported by Bravo et al. (1999), horsegram possesses high nutritional value, containing approximately 25% protein and 60% carbohydrates, besides being a rich source of essential amino acids, energy, fat, iron and molybdenum. Horsegram, also known as a drought-tolerant crop, is commonly grown in India in conditions with nearly 200-700 mm of rainfall and temperatures between 20 and 35 °C. Horsegram is generally suited to a variety of soil types, including stony and gravelly uplands, cleaned harsh forests, deep red loams, black cotton soils, clayey paddy soils, sandy and shallow soils etc. Horsegram is cultivated across almost all states of India owing to its wide adaptability to diverse soil types and climatic conditions. However, nearly 90-95% of the total cultivated area is concentrated in five major states, namely Karnataka (34.0%), Tamil Nadu (18.0%), Maharashtra (18.0%), Odisha (16.0%) and Andhra Pradesh (16.0%), which together constitute the principal horsegram-growing regions of the country. Horsegram occupies about 0.458 million ha in India, producing 0.297 million tonnes with a productivity of 6.48 q ha -1 (Anonymous, 2021) [2] . In Chhattisgarh, it is cultivated on 0.026 million ha with a production of 0.010 million tonnes and a productivity of 3.90 q ha -1 (Anonymous, 2019) [1] . The major horsegram-growing districts are Kondagaon, Jashpur, Kanker and Korba. The crop is predominantly cultivated by tribal farmers in the Northern Hills and Bastar Plateau regions under upland, low-input conditions. Foliar fertilization is an effective nutrient management practice that facilitates rapid nutrient absorption by plants, reduces nutrient losses due to leaching and soil fixation and improves overall nutrient use efficiency (Manonmani and Srimathi, 2009) [10] . In pulse crops, low productivity is frequently attributed to inadequate pod development and poor seed set. The application of nutrients and growth regulators through foliar sprays has been found to enhance reproductive growth, improve pod formation and seed setting, and ultimately increase crop yield (Meena et al., 2017) [11] . The application of nitrogen through foliar feeding at critical growth stages plays an important role in overcoming growth limitations, delaying nodule senescence and improving seed yield (Kumar et al., 2019) [9] . In addition, foliar nutrient supplementation during the pre-flowering and flowering phases minimizes flower drop and enhances reproductive success, resulting in improved crop performance (Beulah and Ghosh, 2020) [3] . ). These treatments were evaluated to assess their effects on nutrient content, nutrient uptake and post-harvest soil nutrient status of horsegram. Foliar application of nutrient of all treatment was done at 25 Days after sowing. The soil of the experimental plot was sandy clay loam in texture, neutral in reaction, medium in organic carbon, low in available nitrogen, medium in available phosphorus and high in available potassium content. Weather conditions during the crop season were favorable for the normal growth and development of horsegram. The experimental crop, horsegram variety Alakh Kulthi, was sown on 28 September 2022 and harvested on 22 January 2023 after attaining physiological maturity. The recommended dose of fertilizer (RDF) was 20:40:10 kg ha -1 of N:P 2 O 5 :K 2 O, respectively. All RDF were applied at the time of sowing as per the treatment specifications. The dried straw and grain were grinded and used for following chemical analysis Nitrogen content was determined by KEL plus unit methods as described by Chapman and Pratt, (1961) [4] . Phosphorus content in the di-acid digest of plant samples was determined by the vanadomolybdo phosphoric yellow colour method and the absorbance was measured at 420 nm using a spectrophotometer, following the procedure outlined by Jackson (1973) [6] . Potassium content in the same digest was estimated using a flame photometer according to the method described by Jackson (1973) [6] . Nutrient uptake was computed by multiplying the nutrient concentration (%) in plant samples by the corresponding seed and straw yields. The soil samples were collected randomly from each experimental plot after the harvest of horsegram. The samples were air-dried, ground and passed through a 2-mm sieve before analysis. The processed soil samples were analyzed to determine the available nitrogen (N), phosphorus (P) and potassium (K) contents. Available nitrogen was determined by the alkaline potassium permanganate method as described by Subbiah and Asija (1956) [13] , available phosphorus was estimated by Olsen's method (Olsen et al., 1954) [12] and available potassium was determined by extracting the soil with neutral normal ammonium acetate and measuring the potassium concentration using a flame photometer following the procedure described by Toth and Prince (1949) [14] .

Methods and materials

Results and Discussion

3.1 Plant analysis 3.1.1 Nitrogen, phosphorus and potassium content in seed and straw (%) Data regarding nitrogen, phosphorus and potassium content in grain and stover of horsegram as influenced by different treatments. The data in respect nitrogen, phosphorus and potassium content in seed and straw of horsegram were not influenced significantly due to different treatments. [8] concluded that total uptake of macro and micronutrients was higher in soybean by foliar sprays of 19:19:19 (0.5%) + H 3 BO 3 (0.5%) + ZnSO 4 (0.5%) at 30 and 40 DAS. Comparable results were obtained by Jaybhaye et al. (2022) [7] and Deore, (2021) [5] .

Treatment Recommended dose of nutrients + 2% NPK 19:19:19 foliar spray (T 7 ) registered the maximum phosphorus uptake in seed, straw and total biomass of horsegram and was statistically at par with treatment Recommended dose of nutrients + 2% DAP spray (T 5 ). Both treatments showed significantly higher phosphorus uptake compared to all other treatments. The lowest phosphorus uptake in seed, straw and total biomass of horsegram was recorded under the control treatment (T 1 ). Comparable results were obtained by Kolekar et al. (2018) [8] , Jaybhaye et al. (2022) [7] and Deore, (2021) [5] .

3.1.5 Potassium uptake in seed and straw (kg ha -1 ) Treatment Recommended dose of nutrients + 2% NPK 19:19:19 foliar spray (T 7 ) recorded the maximum potassium uptake in seed, straw and total biomass of horsegram and was found to be statistically at par with treatment Recommended dose of nutrients + 2% DAP spray (T 5 ). Both treatments significantly outperformed the remaining treatments with respect to potassium uptake. In contrast, the control treatment (T 1 ) registered the lowest potassium uptake in seed, straw and total biomass of horsegram.

Comparable results were obtained by Jaybhaye et al. (2022) [7] and Deore, (2021) [5] .

References

1. Anonymous. Directorate Agriculture (Agriculture Development and Farmer Welfare and Bio-Technology Department). Raipur: Government of Chhattisgarh; 2019.
2. Anonymous. Indiastatagri: season-wise area, production and productivity of kulthi (horsegram) in India, 1967-77 to 202021. New Delhi: Indiastat; 2021.
3. Beulah ED, Ghosh G. Effect of foliar nutrition and plant growth regulators on growth of blackgram (Vigna mungo L.). J Pharmacogn Phytochem. 2020;9(3):1754-1756.
4. Chapman HD, Pratt PF. Methods of analysis for soils, plants and waters. Berkeley (CA): University of California; 1961. p. 169-176.
5. Jackson ML. Soil chemical analysis. New Delhi: Prentice Hall of India Pvt Ltd; 1973.
6. Jaybhaye BB, Takankhar VG, Asati NP, Bodke VS, Pidurkar PK. Effect of foliar application of water-soluble fertilizers on growth, nitrogen uptake and soil available nutrients of black gram (Vigna mungo L.). Pharma Innov J. 2022;11(12):15861591.
7. Kolekar PT, Nawale SS, Zambare PB, Kadlag AD. Yield, quality and nutrient uptake of soybean as influenced by water-soluble fertilizer, micronutrient and plant growth regulators. J Pharmacogn Phytochem. 2018;7(1):2186-2188.
8. Kumar D, Singh RP, Simaiya V. Effect of foliar application of nutrients on yield and economics of blackgram (Vigna mungo L. Hepper) under rainfed vertisols of Central India. J Pharmacogn Phytochem. 2019;8(1):2373-2376.
9. Manonmani V, Srimathi P. Influence of mother crop nutrition on seed yield and quality of blackgram. Madras Agric J. 2009;96(1-6):125-128.
10. Meena D, Bhushan C, Shukla A, Chaudhary S, Meena SS. Effect of foliar application of nutrients on biological yield and economics of urdbean [Vigna mungo (L.) Hepper]. Int J Curr Microbiol Appl Sci. 2017;6(5):2658-2662.
11. Olsen SR, Cole CV, Watanabe FS, Dean LA. Estimation of available phosphorus in soil by extraction with sodium bicarbonate. Washington (DC): United States Department of Agriculture; 1954. Circular No. 939.
12. Subbiah BV, Asija CL. A rapid procedure for the estimation of available nitrogen in soils. Curr Sci. 1956;25:259-260.
13. Toth SJ, Prince AL. Estimation of cation exchange capacity and exchangeable calcium, potassium and sodium content of soil by flame photometer. Soil Sci. 1949;67(6):439-445.