Wood Fibre Properties and Genetic Divergence in Haldina cordifolia (Roxb.) Ridsdale

Abstract

Haldina cordifolia is a multipurpose tree species. It is one of the best Indian timbers suitable for flooring, panelling and for railway carriages. It is also suitable for pulp and paper, construction, window frames, furniture, bobbins, piano keys and rulers. Wood is also used for pencil manufacturing. Though many phyto-chemicals and pharmacological compounds have been identified from this tree species, the species has not been domesticated so far. ICFRE-Institute of Forest Genetics and Tree Breeding, Coimbatore has initiated a tree improvement programme in this tree species since 2018 and plus trees numbering 141 have been selected from the state of Kerala. Eucalyptus spp., Casuarina spp., and Poplars are the major sources of wood pulp used by the paper industries in India. Efforts are being undertaken by various research institutions in India to find alternate indigenous tree species suitable for pulp. Therefore, a study was undertaken to understand the wood fibre properties of select Plus Trees of H. cordifolia. Wood samples collected from 30 select plus trees have been subjected to wood fibre analyses and genetic divergence studies. Wood specific gravity varied from 0.62 to 0.71. Various wood fibre ratios were also studied. Among the 30 Plus Trees studied, HC 01, HC 03, HC 04, HC 05, HC 18, HC 26 and HC 27 have registered ideal values for using them for paper making. The maximum value for broad sense heritability was recorded by Felting coefficient (0.75). Coefficient of fibre flexibility, Isenberg coefficient, Runkel’s ratio and Lumen diameter also registered reasonably higher values for H2. Application of Mahalanobis’ D2 statistics and Tocher’s clustering method resolved 30 Plus Trees into 6 clusters. The cluster strength varied from one in cluster 6 to 21 in cluster 1. The remaining 4 clusters contained two trees each. Genetic divergence studies have shown that Plus Trees namely, HC 22, HC 23, HC24, HC 27, HC 28, HC 29 and HC 30 could be utilized for further tree breeding programmes.