Effect of integrated nutrient management on growth dynamics of sorghum (Sorghum bicolor L.) under Southern Rajasthan

Introduction

Sorghum (Sorghum bicolor L.) is an important cereal crop of the family Poaceae and sub-family Panicoideae. Owing to its remarkable adaptability to diverse environmental conditions, it is extensively cultivated throughout the world during both kharif and rabi seasons. It was originated from Africa, where it was domesticated over 5,000 years ago and has spread throughout the globe. This crop is under the category of hardy nature (prone to drought condition) and cultivated for various purposes like grains, animal feeds, fodder and industrial uses. Sorghum grains contain about 70 per cent carbohydrate, 10-12 per cent protein and 3 per cent fat. It is an excellent source of dietary fiber, iron, phosphorus, B-complex vitamins and is naturally gluten-free. Amongst cereals, sorghum is the 4 th most important crop after rice, wheat and maize. During 2024-25, global area, production and productivity of sorghum were 41.47 million hectares, 63.42 million tonnes and 1530 kg ha -1 , respectively, whereas in India, these were 4.80 million hectares, 6.00 million tonnes and 1250 kg ha -1 , respectively (USDA, 2025) [18] . In the state of Rajasthan during 2024-25, sorghum occupies an area of about 0.64 million hectares with an annual production of 0.54 million tonnes and productivity of 846 kg ha -1 (DA & FW, 2025) [4] . Integrated Nutrient Management (INM), which combines organic manures (like FYM and vermicompost), liquid bio-consortia (such as Azospirillum and PSB) and chemical fertilizers, plays a vital role in improving yield, nutrient uptake and soil health. Sawargaonkar and Wani (2016) [15] found phosphorus combined with N increased sugar and ethanol yield in sweet sorghum at ICRISAT. Mali et al. (2011) [10] observed that K fertilization improved soil fertility and nutrient uptake in long-term trials. FYM is a term used to describe the degraded mixture of farm animal faeces, urine, litter and leftovers from roughages or cow feed. There are 0.5 per cent nitrogen, 0.2 per cent phosphorus and 0.5 per cent potassium in a well-decomposed FYM. Farmyard manure provides many benefits, including enhancing the soil with humus and slowlyreleasing nutrients that aid in retaining water and nutrients while also promoting soil microbial activity. Comparing the organic lettuce production method to the conventional one, a high yield is observed when green manure and FYM are used together (Caliskan et al., 2014) [3] . Vermicompost is one of the most important organic manures used in sustainable agriculture due to its rich nutrient composition, beneficial microbial population and positive effects on soil health. It improves soil physical, chemical and biological properties, enhances nutrient availability and promotes better crop growth and productivity. NPK (nitrogen 1.3-1.7%, phosphorus 0.91-1.12% and potassium 0.85-1.32%) is abundant in vermicompost. Vermicompost is now become very popular and the use of vermicompost has an important input in the integrated plant nutrient management (Singh and Ganguly, 2005) [16] . Bio-fertilizer is generally defined as a material which contains living micro-organism. It is the preparations containing proficient strains of nitrogen fixing, phosphorus solubilizing phototrophic or cellulolytic micro-organism. With several benefits over agrochemicals, liquid biofertilizer formulation is a promising and modernized version of the traditional carrierbased production process. A study found that liquid biofertilizer consortia (Azospirillum + PSB) at 4 ml kg -1 increased biomass and grain yield significantly (Rani et al., 2019) [14] .

Material and methods

A field experiment was conducted at block E1, Instructional Farm, Department of Agronomy, Rajasthan College of Agriculture, MPUAT, Udaipur during kharif, 2025. The experimental soil was clay-loam in texture, slightly alkaline in reaction (pH 7.6), low in organic carbon and available nitrogen, medium in available phosphorus and high in available potassium. The experiment was laid out in a split-plot design with three replications, comprising four fertility levels in the main plot, viz. control, 50% RDF, 75% RDF and 100% RDF and four organic sources in the subplots, viz. control, FYM @ 10 t ha -1 , vermicompost @ 3 t ha -1 and NPK consortia @ 5 l ha -1 . The test crop was sorghum variety CSV 23, sown at a spacing of 45 cm × 15 cm with a seed rate of 10 kg ha -1 . The recommended dose of fertilizer was 80:40:40 kg N:P2O5:K2O ha -1 and half nitrogen with full phosphorus and potassium were applied at sowing through urea, DAP and MOP, while the remaining nitrogen was applied in two equal splits at 30 and 45 DAS. Farmyard manure @ 10 t ha -1 and vermicompost @ 3 t ha -1 were applied 15 days before sowing and incorporated into the soil whereas NPK consortia was applied as seed treatment. The crop was managed through thinning, preemergence atrazine, post-emergence metsulfuron-methyl and hand weeding at critical stages. Observations were recorded on plant height and dry matter accumulation using standard procedures and the data were analyzed by ANOVA as per splitplot design (Panse and Sukhantme, 1985) [12] .

Results and discussion

Fertility levels: During kharif 2025, fertility levels had a significant effect on all growth parameters of sorghum. The results demonstrated that application of 100% RDF recorded the highest values of important growth parameters such as plant height (204.91 cm) and dry matter accumulation plant -1 (123.91 g plant -1 ) at harvest, crop growth rate (CGR), relative growth rate (RGR), leaf area index at 60 DAS (2.34). Plant height remained non-significant at 25 DAS, possibly because seedlings mainly depend upon seed reserves during the early growth stages. However, significant improvement at later stages might be due to improved nutritional status of the plant, which enhanced the synthesis of amino acids, proteins and growth-promoting substances, thereby stimulating meristematic activity, cell division and cell elongation. Similar findings were reported by Sawargaonkar and Wani (2016) [15] and Kubsad (2018) [9] . Dry matter accumulation plant -1 was maximum with the application of 100% RDF. This enhancement might be attributed to improved morphological growth of plants, which facilitated greater interception and efficient utilization of solar radiation, thereby promoting higher photosynthetic activity. Afzal et al. (2012) [1] also reported that higher fertility levels significantly increased plant height and biomass production due to improved nutrient availability and photosynthetic efficiency. Crop growth rate (CGR) and relative growth rate (RGR) also increased significantly with increasing fertility levels due to rapid biomass accumulation and efficient utilization of nutrients. Leaf area index (LAI) was also higher under 100% RDF at different growth stages, possibly due to enhanced nitrogen and potassium availability, which promoted leaf number, leaf growth and leaf surface area. Similar results were reported by Muchow and Carberry (1988) [11] .

Organic sources

Among the organic sources, vermicompost @ 3 t ha -1 recorded significantly higher plant height (200.83 cm), dry matter accumulation (122.47 g plant -1 ), leaf area index (2.32), crop growth rate (CGR) and relative growth rate (RGR), remained statistically at par with NPK consortia for most of the parameters. Correlation studies further revealed a significant and positive relationship between dry matter accumulation at harvest and plant height at harvest (r = 0.812) as well as LAI at 60 DAS (r = 0.856), indicating that improved plant growth and canopy development contributed substantially towards biomass accumulation. The superior growth performance under vermicompost might be attributed to its rich nutrient composition, narrow C-N ratio and faster mineralization, which ensured continuous and balanced nutrient availability throughout the crop growth period. Vermicompost also improved soil structure, aeration, water holding capacity and microbial activity, thereby enhancing nutrient uptake, photosynthetic efficiency and biomass accumulation. Similar findings were reported by Patil et al. (2018) [13] , Tudu et al. (2023) [17] and Balai et al. (2024) [2] . NPK consortia remained statistically at par with vermicompost for most growth parameters, which might be due to the presence of beneficial micro-organisms capable of nitrogen fixation, phosphorus solubilization and potassium mobilization, thereby improving nutrient availability and uptake. Enhanced microbial activity under NPK consortia possibly improved rhizospheric conditions and nutrient use efficiency, resulting in growth performance comparable to vermicompost. Similar observations were reported by Jat et al. (2013) [7] and Deshmukh et al. (2013) [5] . In contrast, FYM recorded comparatively lower growth parameters, which may be attributed to its lower nutrient concentration, wider C-N ratio, slower decomposition and mineralization rate. The nutrients from FYM are released gradually and may not synchronize effectively with crop demand during critical growth stages, resulting in comparatively lower nutrient availability and biomass production. Similar findings were also reported by Krishnaprabu (2014) [8] and Gaikwad et al. (2018) [6] .

Conclusion:

Based on findings, it is proposed that application of 100% RDF recorded the best growth performance in sorghum, with the highest plant height and dry matter accumulation. Among the organic sources, vermicompost @ 3 t ha -1 performed best and was better than NPK consortia, FYM and control. Overall, the combined use of 100% RDF and vermicompost @ 3 t ha -1 was most effective for improving growth of sorghum under Southern Rajasthan conditions.

References

1. -East region of Rajasthan. Journal of Advances in Agronomy and Crop Science. 2024;3(3):1-9.
2. Caliskan S, Yetisir H, Karanlik S. Combined use of green manure and farmyard manure allows better nutrition of organic lettuce. Notulae Botanicae Horti Agrobotanici ClujNapoca. 2014;42(1):248-254.
3. Department of Agriculture and Farmers Welfare. Five Year APY Reports. 2025. Available from: https://upag.gov.in/dash-reports/fiveyearapy/. Accessed October 12, 2025.
4. Deshmukh AD, Sonune BA, Gabhane VV, Mali DV, Rewatkar SS, Ikhe UD. Effect of integrated nutrient management on yield, nutrient uptake and grain quality of sorghum genotypes in Vertisol. Journal of Agriculture Research and Technology. 2013;38(2):318-321.
5. Gaikwad MD, Karanjikar PN, Gaikwad JD, Waghmare PK. Effect of integrated nutrient management on yield, yield attributes and economy of kharif sorghum in Marathawada region. International Journal of Current Microbiology and Applied Sciences. 2018;(Special Issue 6):2953-2957.
6. Jat MK, Purohit HS, Singh B, Garhwal RS, Choudhary M. Effect of integrated nutrient management on yield and nutrient uptake in sorghum. Indian Journal of Agronomy. 2013;58(4):543-547.
7. Krishnaprabu S. Evaluation of vermicompost and biofertilizers on soil properties and yield of sweet sorghum. International Journal of Current Research in Life Sciences. 2014;3(3):191-192.
8. Kubsad VS. Response of rabi sorghum genotypes to different fertility levels under rainfed conditions. International Journal of Current Microbiology and Applied Sciences. 2018;7(10):3282-3286.
9. Mali DV, Kharche VK, Jadhao SD, Katkar RN, Konde NM, Jadhao SM. Effect of long-term fertilization and manuring on soil quality and productivity under sorghum-wheat sequence in Inceptisol. Indian Journal of Agricultural Sciences. 2011;81(5):424-428.
10. Muchow RC, Carberry PS. Effect of nitrogen supply on leaf growth and leaf nitrogen in grain sorghum. Field Crops Research. 1988;18(1):1-16.
11. Panse VG, Sukhatme PV. Statistical methods for agricultural workers. New Delhi: Indian Council of Agricultural Research; 1985.
12. Patil JB, Arvadia MK, Borse DK. Effect of integrated nitrogen management on growth, yield and economics of rabi sorghum under South Gujarat condition. Green Farming. 2018;9(1):76-79.
13. Rani KS, Satish P, Rani CS, Sudhakar C. Effect of liquid biofertilizers on growth and yield of rabi sorghum. Chemical Science Review and Letters. 2019;8(32):190-194.
14. Sawargaonkar SL, Wani SP. Performance of sweet sorghum genotypes under varying nitrogen levels for ethanol production. Current Science. 2016;110(4):715-721.
15. Singh AB, Ganguly TK. Quality comparison of conventional compost, vermicompost and chemically enriched compost. Journal of the Indian Society of Soil Science. 2005;53:352-355.
16. Tudu AK, Palai JB, Shankar T, Adhikary R, Mondal T, Nath S. Effect of integrated nutrient management on growth, yield, nutrient uptake and economics of rabi sorghum. International Journal of Environment and Climate Change. 2023;13(10):4239-4247.