Inter species wood variation of Castanopsis species of Meghalaya

Abstract

Five species of Castanopsis namely C. armata, C. echinocarpa, C. hystrix, C. indica and C. tribuloides of Meghalaya were investigated to study the microscopic features and variation in their wood elements. It is observed that C. armata, C. hystrix and C. indica have semi ring porous wood with distinct growth rings while C. echinocarpa shows diffuse porous to semi ring porous wood with indistinct growth rings and C. tribuloides has semi ring porous to ring porous wood with distinct growth rings. Aggregate rays were observed only in C. armata. Both homocellular and heterocellular rays were present in all species. All Castanopsis species showed the presence of apotracheal diffuse, diffuse in aggregate, paratracheal scanty and vasicentric parenchyma. Tissue proportion measurements of different wood elements showed maximum percentage of fibers and minimum of parenchyma in all selected species. Mean minimum and maximum fiber length, fiber diameter, fiber wall thickness, vessel element length and vessel diameter were recorded as 1329.74 ± 9.03 (C. tribuloides)–1584.57 ± 7.79 μm (C. echinocarpa), 22.72 ± 2.76 (C. indica)–30.30 ± 7.89 μm (C. armata), 7.91 ± 1.77 (C. tribuloides)–8.95 ± 2.10 μm (C. hystrix), 722.28 ± 7.20 (C. tribuloides)–860.81 ± 13.52 μm (C. indica), 225.73 ± 29.49 (C. hystrix)–256 ± 31.06 μm (C. armata). Minimum and maximum vessel frequency were observed as 3.8 per mm2 (C. armata) and 5.2 per mm2 (C. tribuloides), while, minimum and maximum rays per mm were observed in C. hystrix and C. tribuloides. Variance ratio (F test) indicated the occurrence of significant differences among wood element dimensions except wall thickness of Castanopsis. Also, no correlation was observed between these wood elements except vessel frequency and wall thickness (r = −0.931*).