Effect of rhizobium consortia and foliar NPK on growth and yield parameters of greengram (Vigna radiata L.)

Introduction

Pulses are the dried seeds of leguminous plants belonging to the Fabaceae (or Leguminosae) family, which encompasses around 19,400 species across 730 genera-making it the thirdlargest plant family (Bhavya et al., 2024) [17] . Often termed the "poor man's meat," pulses deliver an affordable source of high-quality protein (Azadi et al., 2013) [3] and also supply carbohydrates, vitamins, minerals, Omega-3 fatty acids and dietary fiber (Kumar & Sharma, 2009) [18] . India is not only the world's leading producer of pulses but also one of its largest consumers and importers, meeting domestic demand through imports driven by population growth and rising nutritional awareness (FAO, 2022). According to the Government of India's Crops Division report on the pulses revolution (2017-2018), green gram (Vigna radiata (L.) Wilczek) ranks as the fourth most cultivated pulse in India, with a production of 1.9 million tonnes-behind chickpea (11.1 million tonnes), pigeon pea (4.1 million tonnes) and urd bean (3.2 million tonnes). Dubbed the "green pearl" for its rich nutrient profile (Nayak et al., 2020) [12] , green gram is also known by various names including mung bean, moong, chickasono pea, chiroko, Oregon pea, Chickasaw pea and golden gram (Dhananjoy et al., 2023) [13] . Native to the India-Myanmar region of northeastern Asia (Yang et al., 2011) [19] , green gram has an aromatized variety called "sona mung" that is exclusively cultivated in West Bengal (Saravanan et al., 2013). Seed coat color ranges from green, yellow, and olive to brown, purplish brown, or black, with variability in testa hue and texture contributing to a glossy or matte appearance (Sharma et al., 2004; Kuttimani & Velayutham, 2011) [16,9] . In India, it is grown during the Kharif, Rabi and summer seasons (Prusty, 2022) [4] . In 2017-2018, green gram occupied 4.1 million hectares, yielding 1.9 million tonnes (467 kg ha -1 ). Rajasthan led production with 39.06% of the total, followed by Madhya Pradesh (11.57%), Maharashtra (8.57%), Bihar (5.54%), Karnataka (5.05%), Tamil Nadu (5.02%), Gujarat (4.63%) and Andhra Pradesh (4.31%)-together accounting for 8% of India's overall pulse output (Anonymous, 2023). Mung bean exhibits low tolerance to saline conditions and is particularly vulnerable to iron chlorosis and other micronutrient deficiencies, especially when cultivated in alkaline soils (Muchomba et al., 2023) [11] . The application of nitrogen (N) and phosphorus (P) fertilizers promotes root growth, which in turn enhances the uptake of water and nutrients, leading to an expanded photosynthetic surface and increased dry matter production. Studies have shown that phosphorus application in mung bean significantly boosts dry matter at harvest, the number of pods plant -1 , seeds pod -1 , 1000-seed weight, seed yield and total biomass (Mitra et al., 1999) [10] . Integrated nutrient management (INM) is based on the principle of providing essential nutrients to crops in a manner that sustains productivity while minimizing negative impacts on soil health and the environment. The primary objectives of INM are: to preserve soil fertility, ensure sustainable crop yields, reduce environmental degradation and lower the cost of chemical fertilizer inputs (Sharma et al., 2004) [16] .

Materials and Methods

An experiment was conducted during the Kharif season of 2024 at the Agriculture Research cum Instructional Farm of Barrister Thakur Chhedilal College of Agriculture and Research, Bilaspur (Chhattisgarh). The experimental site is located in Bilaspur district at 22.09°N latitude and 82.15°E longitude. This region falls under the Eastern Plateau and Hill Region of India (Agroclimatic Zone VII). Chhattisgarh is divided into three agroclimatic zones, and Bilaspur lies within the plains zone of the state. The experiment followed a Randomized Block Design (RBD) with three replications and included seven nutrient management treatments: Control (T1), RDF (20:50:25 NPK kg ha -1 ) (T2), RDF + Rhizobium consortia (T3), RDF + NPK foliar spray once @ 40 DAS (T4), 75% RDF + Rhizobium consortia (T5), 75% RDF + NPK foliar once @ 40 DAS (T6) and 75% RDF + Rhizobium consortia + NPK foliar spray once @ 40 DAS (T7). Data were recorded on plant population, plant height, number of branches, dry matter accumulation, number of nodules at different growth stages and yield components including number of pods, pod length, number of grains pod -1 , test weight, grain yield and stover yield at harvest. Post-harvest plant analysis was also performed to assess nitrogen, phosphorus and potassium content and uptake in both grain and straw. Additionally, the economic performance of greengram was evaluated in terms of gross returns, net returns and benefit-cost ratio. The collected data were statistically analyzed using the Analysis of Variance (ANOVA) method.

Results and Discussion

Tables 4.1 and 4.2 present the data on plant height (cm) of greengram as influenced by different nutrient management treatments at 30 and 60 DAS, as well as at harvest. The findings reveal that plant height, number of branches, nodulation and dry matter accumulation were significantly affected by the various treatments throughout all observation stages. At 30 DAS, the tallest plants were observed under treatment T3 -RDF + Rhizobium consortia, statistically significantly superior with T7 -75% RDF + Rhizobium consortia + NPK foliar spray once @ 40 DAS. At 60 DAS and at harvest the data varies in plant height were found significant superior treatment T7 -75% RDF + Rhizobium consortia + NPK foliar spray once @ 40 DAS statistically being at par with T4 -RDF + NPK foliar spray once @ 40 DAS and T3 -RDF + Rhizobium consortia and significantly superior over all the other treatments and T3 -RDF + Rhizobium consortia which observed smaller plant that T7 -75% RDF + Rhizobium consortia + NPK foliar spray once @ 40 DAS and T4 -RDF + NPK foliar spray once @ 40 DAS. The shortest plants were consistently recorded under the T1 (Control). In terms of yield attributes, the highest number of pods and grains plant -1 was recorded in treatment T7 -75% RDF + Rhizobium consortia + NPK foliar spray once @ 40 DAS, but was statistically comparable to T4 -RDF + NPK foliar spray once @ 40 DAS and T3 -RDF + Rhizobium consortia, but it was also significantly better than all other treatments. T3 -RDF + Rhizobium consortia produced the fewest pods and grains compared to T7 -75% RDF + Rhizobium consortia + NPK foliar spray once @ 40 DAS and T4 -RDF + NPK foliar spray once @ 40 DAS. The bare minimum of pods and grains were recorded for treatment T1 -Control. The greatest pod length and test weight of greengram was recorded under T7 -75% RDF + Rhizobium consortia + NPK foliar spray once @ 40 DAS, which was statistically equivalent to T4 -RDF + NPK foliar spray once @ 40 DAS and T3 -RDF + Rhizobium consortia and significantly greater than all other treatments. The T1 (Control) consistently recorded the shortest pods and the lowest test weight. Among the different nutrient management treatments, the highest grain and stover yields were recorded under treatment T7 -75% RDF + Rhizobium consortia + NPK foliar spray once @ 40 DAS. This treatment was statistically on par with T4 -RDF + NPK foliar spray once @ 40 DAS and T3 -RDF + Rhizobium consortia and significantly superior to all other treatments. However, T3 -RDF + Rhizobium consortia yielded less grain and stover than T7 -75% RDF + Rhizobium consortia + NPK foliar spray once @ 40 DAS and T4 -RDF + NPK foliar spray once @ 40 DAS. The lowest grain and stover yields were observed in the control plot (T1). The highest harvest index (40.31%) was also noted in T7 -75% RDF + Rhizobium consortia + NPK foliar spray once @ 40 DAS, surpassing all other treatments, while the control plot (T1) recorded the lowest harvest index at 38.26%.

Conclusion

The findings revealed that growth parameters such as plant height, number of branches, and nodules, along with yield attributes like pod length, number of grains pod -1 , number of pods plant -1 and test weight, were highest under treatment T7 -75% RDF + Rhizobium consortia + NPK foliar spray once @ 40 DAS. This treatment was statistically comparable to T4 -RDF + NPK foliar spray once @ 40 DAS and T3 -RDF + Rhizobium consortia and significantly superior to all other treatments. In terms of yield, the maximum grain and straw yields were also recorded under T7 -75% RDF + Rhizobium consortia + NPK foliar spray once @ 40 DAS, which was statistically at par with T4 -RDF + NPK foliar spray once @ 40 DAS and T3 -RDF + Rhizobium consortia but significantly better than the remaining treatments. Economically, T7 -75% RDF + Rhizobium consortia + NPK foliar spray once @ 40 DAS outperformed all other treatments, recording the highest gross return (117782.90 ₹ ha -1 ) and net return (90741.62 ₹ ha -1 ) and benefit-cost (B:C) ratio (3.36). These economic indicators were followed by T4 -RDF + NPK foliar spray once @ 40 DAS and T3 -RDF + Rhizobium consortia. On the other hand, the lowest gross return, net return and B:C ratio were observed in the control treatment (T1).

References

1. Anonymous. FAO. Food and Agriculture Organization of the United Nations. FAO cereal supply and demand brief. 2022.
2. Anonymous. Ministry of Agriculture and Farmers Welfare, Department of Agriculture and Farmers Welfare, Directorate of Economics and Statistics. 2023.
3. Azadi E, Rafiee M, Hadis N. The effect of different nitrogen levels on seed yield and morphological characteristic of mung bean in the climate condition of Khorramabad. Annals of Biological Research. 2013;4:5155.
4. Bhabai B, Mukhopadhyay D, Mitra B. Effect of biofertilizer and phosphorus on green gram (Vigna radiata). Journal of Pharmacognosy and Phytochemistry. 2019;8(4):505-509.
5. Bhat MI. Combined effects of rhizobium and vesicular arbuscular fungi on greengram (Vigna radiata L. Wilczek) under temperate conditions. Res J Agri Sci. 2011;2(1):1720.
6. Ghosh MK, Joseph SA. Influence of biofertilizers, foliar application of DAP and sulphur sources on yield and yield attributes of summer greengram (Vigna radiata L. Wilczek). Legume Research-An International Journal. 2008;31(3):232-233.
7. Kamaleshwaran R, Karthiga S. Effect of foliar nutrition on yield and growth parameters of greengram in coastal area of Tamil Nadu (Vigna radiata cv. Vamban 2). International Multidisciplinary e-Magazine. 2021;1(3):22-27.
8. Kundu R, Mandal J, Majumder A. Growth and production potential of greengram (Vigna radiata) influenced by Rhizobium inoculation with different nutrient sources. International Journal of Agriculture, Environment and Biotechnology. 2013;6(3):419-426.
9. Kuttimani R, Velayutham A. Foliar application of nutrients enhances the yield attributes and nutrient uptake of greengram. Agricultural Science Digest-A Research Journal. 2011;31(3):202-205.
10. Mitra S, Bhattacharya SK, Datta M, Banik S. Effect of variety, rock phosphate and phosphate solubilizing bacteria on growth and yield of greengram in acid soils of Tripura. Environment and Ecology. 1999;17:926-930.
11. Muchomba MK, Muindi EM, Mulinge JM. Overview of green gram (Vigna radiata L.) crop, its economic importance, ecological requirements and production constraints in Kenya. Journal of Agriculture and Ecology Research International. 2023;24(2):1-11.
12. Nayak S, Nayak D, Parida S. Micronutrient foliar spray on growth performance of green gram (Vigna radiata L.). Asian Journal of Biological and Life Sciences. 2020;9(2):235-235.
13. Dhananjoy P, Mondal R, Banerjee S. Effect of foliar nutrition on growth and yield of greengram (Vigna radiata L.) in red and lateritic soils of West Bengal. Journal of Food Legumes. 2023;36(1):93-97.
14. Prusty AA. Effect of foliar application of nutrients and plant growth regulators on yield and yield attributing characters of greengram (Vigna radiata L.). 2022:1229-1235.
15. Saravanan P, Singh SK, Kumar I. Effect of organic manures and chemical fertilizers on the yield and macronutrient concentrations of greengram. International Journal of Pharmaceutical Science Invention. 2013;2(3):1-6.
16. Sharma KL, Srinivas K, Mandal UK, Vittal KPR, Grace KJ, Maruthi SGR. Integrated nutrient management strategies for sorghum and greengram in semi-arid tropical Alfisol. Indian J Dryland Agric Res Dev. 2004;19:13-23.
17. Bhavya EP, Raman M. Comprehensive review on synthesis of nano starch and its applications in food packaging industry. Journal of Packaging Technology and Research. 2024 Oct;8(3):153-66.
18. Sharma S, Dwivedi PR, Kumar MK, Davari S, Shukla MR. 2010. Comics for All: World Comics India Bulletin. 2009.
19. Yang X, Li L. miRDeep-P: a computational tool for analyzing the microRNA transcriptome in plants. Bioinformatics. 2011 Sep 15;27(18):2614-5.