Growth status and site quality of different seed production areas of teak (Tectona grandis L. f) in Karnataka, India

Abstract

In the present study 20 SPAs of teak distributed in southern, central and northern parts of Karnataka, India are selected. Phenotypic parameters of standing trees of different SPAs were recorded. Further, seed yield was also recorded and compared with site quality and stand growth parameters. Result showed that there was a greater variation among SPAs for phenotypic growth characters as well as site quality. The overall growth of SPAs of Madikeri zone (Southern region) was found to be superior with respect to tree height, clear bole height and DBH.SPAs belonged to Dandeli (Northern region) recorded more DBH and nearly round stem. SPAs of Yallapur seed zone showed comparatively less growth over Madikeri zone. SPA of Dandeli zone recorded the more tree volume and top height, followed by SPA of Madikeri zone. Considering site quality of different SPAs, all the studied SPAs of Karnataka are growing under relatively poor site conditions. Sixteen out of twenty SPAs, nearly 80% were growing in areas with site quality classes IV and V. Interestingly, none of the studied SPAs belonged to either class I or II. Association study showed that tree height (r=0.403) and clear bole height (r=0.412) showed positive relationship with seed yield. Furthermore, site quality showed a weak positive relationship with seed yield (R2 =0.052) among SPAs indicating poor site quality could be a major factor for low seed yield. It is concluded that SPAs of Madikeri and Dandeli zones performed better in growth and stem form. Therefore, it is suggested to collect quality seeds from these seed zones.