MOLECULAR CHARACTERIZATION AND COMPARATIVE ANALYSIS OF PHYSICAL AND CHEMICAL SOIL PROPERTIES UNDER DIFFERENT AGROFORESTRY SYSTEMS IN EASTERN UTTAR PRADESH

Abstract

The present study was conducted during 2023–2026 in Eastern Uttar Pradesh to evaluate tree species diversity, molecular genetic variability, and physicochemical soil properties under different agroforestry systems, namely Agrihorticulture, Agrisilviculture, Agrisilvihorticulture, Boundary Plantation, and Silvipastoral systems. Tree vegetation was assessed through phytosociological analysis using parameters such as population density, basal area, relative density, Importance Value Index (IVI), Shannon Diversity Index (H′), and Dominance Index (Cd). Molecular characterization of selected tree species was carried out using Random Amplified Polymorphic DNA (RAPD) markers to assess genetic diversity and similarity among species. Soil samples collected from different agroforestry systems and soil depths were analyzed for bulk density, particle density, pore space, pH, electrical conductivity, organic carbon, and available nitrogen, phosphorus, potassium, and sulfur. The results revealed considerable variation in vegetation structure among agroforestry systems. The Silvipastoral system recorded the highest Shannon Diversity Index (H′ = 3.1019) and lowest Dominance Index (Cd = 0.0567), indicating greater species diversity and ecological stability, whereas Boundary Plantation exhibited the lowest diversity (H′ = 1.611) and highest dominance (Cd = 0.278). Species such as Mangifera indica, Tectona grandis, Dalbergia sissoo, and Eucalyptus spp. showed higher IVI values and contributed significantly to stand structure. RAPD analysis generated 11–18 amplified bands with polymorphism ranging from 76.92 to 83.33%, demonstrating substantial genetic variability among the studied species. The highest polymorphism was observed in Eucalyptus spp. (83.33%), while Mangifera indica exhibited the highest genetic similarity index (0.90). Significant differences were also observed in soil physical and chemical properties among agroforestry systems. Diversified systems, particularly Agrisilvihorticulture and Silvipastoral systems, recorded lower bulk density, higher pore space, and greater organic carbon accumulation compared with Boundary Plantation and less diversified systems. Soil pH and electrical conductivity remained within acceptable ranges across all systems. Available nitrogen, phosphorus, potassium, and sulfur contents were significantly higher in diversified agroforestry systems, reflecting enhanced litter deposition, root turnover, and nutrient cycling. Nutrient availability and organic carbon generally declined with increasing soil depth, indicating greater biological activity in surface layers. The study demonstrates that diversified agroforestry systems, especially Silvipastoral and Agrisilvihorticulture systems, support higher biodiversity, conserve genetic resources, improve soil fertility, and enhance ecosystem sustainability. These systems offer promising land-use options for increasing productivity, environmental resilience, and sustainable agricultural development in Eastern Uttar Pradesh.