Characterization of Butea monosperma phenotypes in Madhya Pradesh: Implications for forest conservation and breeding programs

Introduction

Butea monosperma (Lam.) Taub. also known as the flame of the forest or palash, is a prominent deciduous tree species in the Indian subcontinent. Widely distributed across tropical and subtropical regions of India, Nepal, Sri Lanka, and Bangladesh, it is a crucial part of dry deciduous forests (Burli and Khade, 2007) [1] . The tree is particularly valued for its diverse uses, including its vibrant flowers, edible gum, seeds, and durable timber. These components play significant roles in both the local economy and traditional medicine, especially in rural communities (Gupta et al., 2017) [3] . The flowers of B. monosperma are widely recognized for their medicinal and dyeing properties. The tree's name "flame of the forest" reflects the striking orange-red flowers that are used in traditional medicine for treating wounds and infections (Rizvi et al., 2024). The gum, known as Butea gum, has astringent and antimicrobial properties, making it an essential component in Ayurvedic treatments (Mazumder et al., 2011) [4] . Moreover, the seeds produce oil that has culinary and medicinal uses, while the wood is employed in the construction of tools and furniture (Methaniya et al., 2023) [5] . Ecologically, B. monosperma plays a critical role in maintaining soil health and supporting biodiversity. Its deep root system contributes to soil stabilization, especially in semi-arid and degraded lands, making it a valuable species in afforestation and agroforestry projects (Burli and Khade, 2007) [1] . The tree is also a host for the lac insect (Kerria lacca), which produces shellac, a valuable resin used in various industries (Mazumder et al., 2011) [4] . Despite its wide range of applications, B. monosperma faces numerous challenges, particularly related to overexploitation and poor natural regeneration. The increasing demand for its flowers, gum, and wood has led to habitat degradation, while climate change further complicates its regeneration (Rathnaprabha et al., 2017) [9] . These pressures underscore the importance of developing effective conservation and breeding strategies to safeguard the species' future. One promising approach to addressing these challenges is the Individual Tree Selection (ITS) method, a technique used in tree breeding and genetic improvement. ITS involves selecting superior trees based on phenotypic traits such as growth rate, flowering intensity, and reproductive potential. These selected trees serve as breeding material for the development of high-yielding and resilient varieties that can better withstand environmental stresses (Zobel and Talbert, 1984) [14] . This method holds potential for improving the productivity of B. monosperma, ensuring its sustainability for future generations. This study aims to identify superior B. monosperma trees in Madhya Pradesh, focusing on three districts; Chhindwara, Mandla, and Balaghat. By evaluating the phenotypic characteristics of trees in these regions, we aim to select superior genotypes for breeding programs that can enhance the species' productivity, resilience, and overall sustainability. This study aims to identify and select superior Butea monosperma trees from Madhya Pradesh, India, for breeding and conservation efforts. A total of 10 trees will be selected based on their outstanding phenotypic characteristics, which will serve as the foundation for future breeding programs and sustainable management of the species.

Methodology Study Area

The study was conducted in the natural forests of Madhya Pradesh, focusing on three key districts: Chhindwara, Mandla, and Balaghat. These regions are located in the central part of Madhya Pradesh and are known for their rich forest biodiversity, including significant populations of Butea monosperma (Flame of the Forest). The forests in these areas provide an ideal environment for the growth of this species, characterized by a tropical and subtropical climate that supports robust tree growth and reproductive potential.

Sampling and Tree Selection

In total, 30 Butea monosperma trees were randomly selected from the natural forests of Chhindwara, Mandla, and Balaghat, with 10 trees selected from each district. The trees were chosen using the Individual Tree Selection (ITS) method, which is a common practice in forest tree improvement. This method involves selecting individual trees based on superior phenotypic traits that reflect the genetic potential of the species. The selected trees were mature, aged over 20 years, and displayed phenotypic traits that indicated high productivity and vitality.

Selection Criteria

The selection of superior trees was based on the following phenotypic traits, which are critical for evaluating the overall fitness and potential of the trees: 1. Tree Height: The height of each tree was measured to assess its growth potential. Taller trees are typically indicative of better overall health and vigor.

Girth at Breast Height (GBH):

The circumference at 1.3 meters above ground level was recorded for each tree to measure its stem diameter. Larger girth values are associated with better growth and reproductive capacity.

Crown Spread:

The horizontal spread of the tree's crown was measured along both the north-south and east-west axes. A broader crown spread suggests a higher level of canopy development, which is important for photosynthesis and overall tree productivity. 4. Flowering Intensity: The flowering intensity was visually assessed on a scale of 1 to 5, with 1 representing minimal flowering and 5 representing abundant flowering. Strong flowering intensity is crucial for seed production and reproductive success.

Fruit Yield:

The quantity and weight of fruit produced by each tree were recorded. Higher fruit yield is indicative of the tree's reproductive fitness and potential for seed collection.

Data Collection

Data was collected during the flowering and fruiting seasons to capture the full spectrum of phenotypic traits. The following methods were employed to measure the traits (Chaturvedi and Khanna, 1994) [2]: 1. Tree Height Measurement: The height of each selected tree was measured using a Ravi multimeter to ensure accurate measurements 2. GBH Measurement: The girth at breast height was measured using a standard measuring tape at 1.37 meters from the ground 3. Crown Spread Measurement: The crown spread was measured by calculating the distance between the furthest branches along the north-south and east-west axe.

Flowering Intensity Rating:

Flowering intensity was rated on a scale of 1 to 5 based on visual observation, with higher scores assigned to trees with more abundant and vibrant flowers Olubode et al. (2015) [6] .

Fruit Yield Estimation:

The number of pods and the total weight of fruits from each tree were recorded during the peak fruiting season to estimate the overall fruit yield (Shukla et.al. 2014) [11]

Statistical Analysis

The collected data was analyzed using descriptive statistics and trees exhibiting superior phenotypic traits, such as taller height, larger GBH, more extensive crown spread, stronger flowering intensity, and higher fruit yield, were identified as candidates for future breeding programs. These superior trees will be used for seed collection and genetic improvement efforts aimed at enhancing the productivity and resilience of Butea monosperma in the region.

Results

The morphological and reproductive traits of Butea monosperma trees exhibited noticeable variation across the three districts of Madhya Pradesh; Chhindwara, Mandla, and Balaghat as presented in Tables 1,2, and 3. [13] , who reported substantial genetic diversity and population differentiation in B. monosperma across India, indicating that local environmental conditions such as Mandla's favorable soils and microclimate may enhance both vegetative growth and reproductive success. The high flowering and fruit yield in Mandla also align with the species' mixed mating system and propensity for geitonogamy noted by Tandon et al. (2003) [12] , suggesting that higher pollinator activity or greater genetic compatibility may be contributing factors. The variation observed among districts likely reflects a combination of genetic differences and localized environmental influences. Limited gene flow, as documented in B. monosperma (Vashishtha et al., 2013) [13] , can lead to population-specific adaptations and trait divergence.

From a management perspective, Mandla populations offer valuable germplasm for seed collection, propagation, and breeding programs, while Balaghat populations may warrant targeted conservation efforts to preserve unique local genotypes adapted to less favorable conditions.

Conclusion

The comparative evaluation of Butea monosperma across Chhindwara, Mandla, and Balaghat districts revealed clear population-level differences in both morphological and reproductive traits. Mandla emerged as the most productive population, with superior tree height, GBH, crown spread, flowering intensity, and fruit yield, coupled with relatively low variability, making it an ideal source for seed collection, clonal propagation, and breeding programs. Chhindwara populations displayed intermediate performance, while Balaghat populations though lower in overall growth and reproductive output, may harbor unique genotypes adapted to local conditions that merit conservation attention.These findings highlight the combined influence of genetic makeup and local environmental factors on population performance in B. monosperma. Targeted utilization of high-performing populations, alongside conservation of genetically distinct but less productive ones, can support sustainable management, genetic improvement, and longterm conservation of this ecologically and economically valuable species.

References

1. Burli DA, Khade AB. A comprehensive review on Butea monosperma (Lam.) Kuntze. Pharmacogn Rev. 2007;1(2):333-337. Available from: http://phcogrev.com
2. Chaturvedi AN, Khanna LS. Forest mensuration. Dehradun: International Book Distributors; 1994. p. 403.
3. Gupta AP, Bhardwaj AK, Yadav S. Ethnomedicinal uses of Butea monosperma (Lam.) Taub. in tribal regions of India. Indian J Tradit Knowl. 2017;16(3):451-456.
4. Mazumder PM, Das MK, Das S. Butea monosperma (Lam.) Kuntze -A comprehensive review. Int J Pharm Sci Nanotechnol. 2011;4(2):1390-1393. doi:10.37285/ijpsn.2011.4.2.2
5. Methaniya D, Rathore R, Solanki H. Butea monosperma: Ethnomedicinal studies and pharmacology: A review. Int Assoc Biol Comput Dig. 2023;2(1). doi:10.56588/iabcd.v2i1.140
6. Olubode O, Adekola S, Idowu S. Evaluation of flowering pattern, yield and yield determinants of Hybrid Tea Rose in response to seasonal variations and applied organic manure rates. Am J Plant Sci. 2015;6(3):464-482. doi:10.4236/ajps.2015.63052
7. Prasad R, Arunachalam A, Alam B, Handa AK, Ram A, Singh P, et al. Assessment of seasonal variability in gum exudation and gum yield in Palash (Butea monosperma L.) in semi-arid region of Central India. Indian J Agrofor. 2024;26(2). Available from: https://ebook.icar.gov.in/index.php/IJA/article/view/159 264
8. Kuntze) flower of the Malwa plateau region of India. Indian J Agrofor. 2024;26(2). Available from: https://epubs.icar.org.in/index.php/IJA/article/view/134 946
9. Rizvi F, Khan MA, Saquib M, Khan MF. Butea monosperma: Phytochemistry and pharmacological applications. In: Metabolites of medicinal plants: Insightful approaches. Sharjah: Bentham Science Publishers; 2024. p. 53-66. doi:10.2174/97898152741031240101
10. Shukla U, Srivastava V, Singh S, Sen A, Kumar V. Growth, yield and economic potential of rice (Oryza sativa) as influenced by different age of seedlings, cultivars and weed management under system of rice intensification. Indian J Agric Sci. 2014;84(5):628-636.
11. Zobel B, Talbert J. Applied forest tree improvement. New York: Wiley; 1984.