Pulses are a from nature because of their special ability as efficient source of protein in a typical Indian diet. Pulses hold an important position in Indian agriculture. (Ghosh et al., 2022). Black gram, native to Indian subcontinent, found a remarkable resemblance to Vigna radiata (Reddemma et al., 2024). India is the world’s leading producer of black gram; however, numerous tropical and subtropical countries in Asia, Africa and Central America also contribute to black gram production (Rajput et al., 2021). The total black gram cultivation area in India is 4.8 million ha. Madhya Pradesh ranked 1^st position in India in area and production (37% and 32%, respectively) followed by Andhra Pradesh (8% and 13%, respectively). In India, the total production of black gram is 2.73 million tons, while the productivity is 5.64 quintal ha^-1.

Boron (B) is an important non-metallic micronutrient that is crucial for maintaining structure of cell walls, cell division, membrane stability, nitrogen uptake, sugar translocation, K+ transport, protein and sucrose synthesis, phenol, carbohydrate, nucleic acid and IAA metabolism. It has been found that the available boron in Indian soils ranges from 0.04 to 7.40 mg kg^-1, while the total boron concentration varies between 3.80 and 630 mg kg^-1 (Kumar et al., 2020). Boron deficiency is more common in low organic matter concentration. Boron is kept in soils through adsorption in minerals and humic particles and the formation of insoluble precipitates. It was reported that 33% of Indian soils may be deficient in Boron. Reproductive growth is reportedly limited by boron deficit (Jasper et al., 2022). Since many crops’ roots (such pulses) may reach beyond the surface layer to obtain some nutrients from subsurface layer, knowledge on depth-wise distribution of soil’s accessible boron is desirable. Because boron is a less mobile nutrient in plants, deficiency symptom of boron initially appears on the tips of stems, young leaves, flowers and buds. The symptoms of boron deficiency in plants also include dieback of tips of the shoots, downward cupping of the leaves and dark green, leathery leaves. Boron’s significance in plant physiology stems from its involvement in several fundamental processes. It is indispensable for maintaining the structural integrity of cell walls by facilitating the cross-linking of pectic polysaccharides, which contribute to cell wall strength and flexibility (Marschner, 1995). This structural role is particularly important during periods of rapid cell division and elongation, such as in growing shoots and roots. Furthermore, boron aids in the transport of sugars by forming sugar-borate complexes, which are essential for energy distribution and supporting metabolic demands during growth (Brown et al., 2002).

A field experiment was conducted during summer 2024 at the crop research centre (CRC) farm of Kaliawash, SGT University, Gurugram, Haryana, located at 28.48’ North latitude and 76.89’ East longitude and at an altitude of 217 meters above mean sea level. The crop research centre is located in the north-western zone of Haryana. Soil samples were collected randomly from different treatments of the experimental field at a depth of 0-15 cm to determine the physiochemical properties of soil. A representative composite sample was then analyzed to assess the physio-chemical properties of the soil using standard methods. The analytical results revealed that the soil of experimental field was sandy loam in texture, slightly alkaline in chemical reaction, had low available nitrogen and medium available phosphorus, potassium, sulfur and deficient micronutrients. The experiment was laid out with seven treatments, viz. Control T₁: Recommended dose of fertilizer N:P:K (20: 40: 40 kg ha^-1), T₂: RDF +foliar application boron 0.5% @ 30  and 45 DAS, T₃: RDF + foliar application boron 1% @ 30  and 45 DAS, T₄: RDF + foliar application of boron 1.5% @ 30  and 45 DAS, T5: RDF + foliar application of boron 2% @ 30  and 45 DAS, T6: RDF + foliar application of boron 2.5% @30  and 45 DAS, T7: RDF + foliar application of boron 3% @ 30  and 45 DAS, in randomized block design with three replication. Black gram variety (T₉) with plant geometry (30 cm × 25 cm) was sown in mid-April 2024. The data on growth parameters like plant height, number of branches, number of trifoliate leaves, number of pods and number of nodules were recorded from 5 randomly selected plants. Harvested plant samples were sun-dried for 4-5 days and biological yield was recorded threshing was done manually and the grain weight was subtracted from biological yield to get straw yield and calculation economics.

The data related to different growth and yield parameters such as plant height, number of branches, number of trifoliate leaves plant^-1, number of nodules plant^-1, number of pod plant^-1, number of grains pod^-1, test weight, biological yield and yield (q ha^-1) as influenced by the application of Borax as source of Boron with certain treatments are explained below.

Plant height
 
Foliar treatments applied in combination significantly increased the plant height of Black gram, as shown in Table 1. The highest plant height was recorded as 19.52 cm at branching stage under treatment combination T₅ which was found to be statistically at par with treatments T₆ and T₃ and significantly superior to other treatments. Again, maximum plant height was 36.20 cm at harvest under treatment combination T₅ which was found to be statistically at par with treatments T₄ and T₃ whereas it was found to be significantly superior to all other treatments. Treatment T₁ (RDF) recorded the lowest plant height of 13.20 cm and 20.86 cm at branching and at harvest stage. Similar finding was reported by Singh et al., (2017) and Erol (2024).


 
Number of branches plant^-1
 
Data on number of branches per plant as influenced by boron recorded at two growth phases like branching stage and at harvest (Table 1). At branching stage, maximum number of branches per plant (11.16) was recorded under the treatment combination T₅ which was statistically par with treatments T₆ and T₄ and significantly superior to other treatments. At harvest, maximum number of branches per plant was 28.12 under the treatment combination T₅. Further, treatment T₅ was followed by T₄ and T₃ regarding number of branches per plant. T₅: RDF + foliar application of 2% boron @ 30 and 45 DAS, respectively. The minimum number of branches per plant was 9.36 at branching stage and 16.66 at harvest stage was observed in treatment T₁ (RDF). A similar result was found by Naznin et al., (2020).
 
Number of trifoliate leaves plant^-1
 
The data regarding the number of trifoliate leaves per plant, as affected by the treatments, recorded at two growth stages, are presented in Table 1. The highest number of trifoliate leaves per plant was recorded as 17.66 at branching stage which was found to be statistically at par with treatments T₃ and T₄ and at harvest the maximum number of trifoliate leaves per plant was recorded in T₅: RDF + foliar application of 2% boron at 30 and 45 DAS, is 36.86 this was followed by treatment T₄ and T₃. The lowest number of trifoliate leaves per plant 12.46 at branching and 18.60 at harvest stage was recorded with treatment T₁ (RDF). A similar result was found by Meena et al. (2016).
 
Nodulation
 
The data on number of nodules per plant at flowering stage are presented in Table 1. The maximum number of nodules per plant was obtained under treatment T₅: RDF + foliar application (F.A.) of 2% boron at 30 and 45 DAS, which was 17.32 and found to be statistically at par with treatments T₄ and T₃ and significantly superior to rest of the treatments. The minimum number of nodules per plant was obtained under treatment T₁ (RDF), which was 10.60. A similar report was found by Mishra et al., (2018) and Muddana et al., (2025).

Number of pods plant^-1
 
Data on number of pods per plant of black gram, as influenced by various treatments, are presented in Table 2. All the treatments significantly increased the number of pods per plant compared to T₁ (RDF). Treatment T₅: RDF + foliar application (F.A.) of 2% boron at 30 and 45 DAS resulted in maximum number of pods per plant at harvest 18.00, which was followed by treatments T₄ and T₆ and these treatments are significantly at par to each other which produced 15.80 and 15.20 pods per plant, respectively. A similar result was found by Mondal et al., (2024).


 
Number of grains pod^-1
 
The quantity of grains per pod at harvest stage was substantially impacted by the treatments, as shown in Table 2. Treatment T₅: RDF + foliar application (F.A.) of 2% boron at 30 and 45 DAS had maximum number of grains per pod (8.20), whereas treatment T₁ (RDF) had the lowest number of grains per pod (5.22). Similar was reported by finding Banerjee et al. (2023).
 
Test weight
 
The data test weight presented in Table 1 revealed that the highest test weight (42.22 g) was recorded with T₅: RDF + foliar application (F.A.) of 2% boron at 30 and 45 DAS, which was superior to all other treatments. However, this treatment is followed by T₂ (37.12 g), which is at par to T₃ (37.00 g). A similar result was also reported by Mondal et al., (2024).
 
Biological yield
 
The data in Table 2 indicated that various treatments significantly influenced biological yield. The maximum biological yield (32.36 q ha^-1) was concluded with treatment T₅: RDF + foliar application (F.A.) of 2% boron at 30 and 45 DAS, which was found to be statistically at par with treatments T₄ and T₃ and significantly superior to other treatments. The lowest biological yield (24.05 q ha^-1) was recorded in treatment T₇ (RDF + foliar application (F.A.) of 3% boron at 30 and 45 DAS). A similar result was found by Jyothika et al., (2023).
 
Grain yield
 
The study observed a variation in yield ranging from 10.02 q ha^-1 to 12.54 q ha^-1, indicating a 25.14%, 19.50% and 15.56% increase in yield treatment T₅, T₄ and T₃ respectively increase in yield and these are significant and at par with each other and the lowest yield is recorded in treatment T₇. The treatment T₅-RDF + (FA) B@2% at 30 and 45 DAS recorded the highest yield. The application of boron at an optimal concentration @ 2% B significantly enhanced yield, while the excessive application @ 3% B resulted in a decline in yield due to toxicity of Boron in soil. A similar result was found by Mishra et al., (2018).
 
Effect of treatments on the economics of black gram
 
The effect of application of boron on the economics of black gram is described in Table 2. Maximum gross returns (Rs.92,796 ha^-1), net returns (Rs.49,703 ha^-1) and B: C ratio (2.15) were recorded in treatment T₅: RDF + foliar application (F.A.) of 2% boron at 30 and 45 DAS. With a greater magnitude of yield enhancement, the marginal increase in production costs related to other treatments resulted in better yields, gross returns, net returns and benefit-cost ratios.
 

The experimental findings indicate that the treatment T₅ with recommended dose of fertilizers (RDF) combined with foliar application of 2% boron at 30 and 45 days after sowing (DAS) was the most effective in enhancing the growth, yield and economic returns of black gram (Vigna mungo L.). The application of RDF along with foliar application of 2% boron at these critical growth stages resulted in significantly higher yield. Based on the results of this study, it is recommended that black gram cultivation with RDF and foliar application of 2% boron at 30 and 45 DAS to optimize yield potential and economic profitability.

I would like to express my sincere gratitude to all those who supported me throughout this research. First and foremost, I sincerely thank my supervisor, Dr. Shakti Om Pathak, for their invaluable guidance, constructive feedback and continuous encouragement throughout this study.

I am also thankful to the faculty and staff of the Faculty of Agricultural Sciences, SGT University, for providing necessary resources and a conducive environment for research. Special thanks to my friends who provided support, insightful discussions and moral encouragement.
 
Disclaimer
 
The views and opinions expressed in this research paper are those of author and do not necessarily reflect the official policy or position of any affiliated institutions, organizations, or funding agencies. The authors are solely responsible for the content and accuracy of data and analysis presented herein. Any error or omission is the responsibility of author.
 
Informed consent
 
All participants voluntarily took part in this study after receiving detailed information about its purpose and procedures. Written consent was obtained and confidentiality was assured. Participants were free to withdraw at any time. The study adhered to ethical guidelines approved by the appropriate institutional ethics committee.

The authors declare no conflict of interest. The research was conducted independently and no financial or personal relationships influenced the outcome or interpretation of findings.