Physico-chemical and Thermochemical Profiling of Mulberry (Morus spp.) Clones for Sustainable Bioenergy Application: A PCA-based Selection Approach for Sustainable Bioenergy Application

Abstract

Background: Energy demand in recent decades has surged due to rapid industrialization, population growth, and lifestyle changes. In India, most people live in rural areas and depend on biomass fuel wood for energy, leading to a significant increase in the country's energy requirements. In order to fulfill the energy, need the people mostly focuses on using fuel wood as their source of energy because they are easily available and cheaper than fossil fuel. Aims: The study aimed to evaluate the physico-chemical and thermochemical characteristics of mulberry (Morus spp.) clonal genetic resources to assess their suitability as alternative renewable feedstock for bioenergy and fuelwood applications. Study Design:  A Completely Randomized Design (CRD) was adopted for the experimental layout, and statistical analysis was performed using SPSS (version 23) and PCA was conducted using XLSTAT 24. Place and Duration of Study: The research was conducted at the Department of Sericulture, Forest College and Research Institute, Mettupalayam, Tamil Nadu, during 2023–2024. Methodology: The wood of seventeen mulberry clones viz., Morus alba (MI-0674, ME-0174, MI-0145, MI-0211, MI-0828, MI-0300, ME-0169, MI0034), Morus latifolia (MI-0665, ME-0006, MI-0783, ME-0168, MI-0549, MI-0632, MI-0818, MI-0845), and Morus laevigata (MI-0532), were assessed for their bioenergy potential based on parameters such as moisture content, bulk and basic density, specific gravity, alcohol-benzene extractives, acid-insoluble lignin, holocellulose, ash content, volatile matter, fixed carbon, calorific value, higher heating value (HHV), and fuel value index (FVI). Standard protocols were followed for all analyses. Results: Significant variation (P < 0.05) was observed among clones for all assessed traits. Moisture ranged from 29.97% to 41.10%, and basic density from 619.09 to 701.80 kg m⁻³. Calorific value and HHV ranged from 16.76 to 19.34 MJ kg⁻¹ and 18.73 to 20.64 MJ kg⁻¹, respectively. PCA identified five principal components explaining 85.092% of total variance, with MI-0845, ME-0168, and MI-0674 showing superior bioenergy profiles. Moisture content is a critical determinant of the combustion characteristics and fuel efficiency of biomass. High moisture levels are generally associated with reduced calorific value, diminished combustion efficiency, and increased operational costs due to higher energy consumption for drying and increased transportation weight. PCA results indicated that clones MI- 0845, MI- 0674, ME- 0168 ranked highly in PC1. While, clones like MI- 0845, MI- 0674, MI- 0034, and MI- 0532 appeared across multiple components, demonstrating their versatility and overall strong performance in contributing to the variability observed in the dataset. This ranking provides valuable insights into the mulberry clones that are most effective or influential for fuelwood and bioenergy production, guiding future selection and breeding strategies to establish mulberry as a sustainable alternative for bioenergy production. Conclusion: The study highlights the potential of select mulberry clones as sustainable bioenergy sources, supporting their strategic utilization in renewable energy and agroforestry systems.