Influence of Salix Planting Density and Clonal Variation on Aphid Infestation

This study assessed the effects of planting density and clonal variation on growth traits and aphid (Tuberolachnus salignus) infestation in four Salix clones under short rotation forestry. Clones were planted at three spacings (1×1, 1×2, 2×2 m) in a factorial randomized block design. Growth parameters and aphid incidence were significantly influenced by spacing, clone, and their interaction. UHFS 141 showed the highest volume index (37,803.86 cm³) at 2×2 m spacing. Aphid infestation was highest under dense planting (1×1 m), with NZ 1140 recording the most colonies (6.2/tree), while UHFS 119 at 2×2 m had the least (0.4 colonies/tree). Imidacloprid 17.8 SL @ 0.3 ml/L effectively reduced aphid populations, followed by Neem oil @ 30 ml/L. Results highlight the importance of integrating optimal spacing, clone selection, and pest management for improved Salix productivity.