Plus Tree Selection and Progeny Testing for Establishment of First Generation Seed Orchard in Dalbergia sissoo Roxb

Abstract

Intensive survey of Northern India and southwestern region of Nepal was conducted during January-February, 1998 in order to select plus trees of shisham (Dalbergia sissoo Roxb.). Sixty-three plus trees were selected on the basis of good height, diameter, clear bole (without forking), stein straightness, aggressively apical dominance, compact crown, low branch angle and resistant to pest and diseases. Plus trees of Dalbergia sissoo Roxb. were found much more straight and tall up to 37.4 m in Sirsa-Dabwali (Haryana), Tanakpur (U.P.) and Dhangarhi (Nepal). Significant differences were observed between progenies of different origins as well as among progenies of same origin for growth characters and stem form at the age of 15 months after transplanting. Ample genetic variations were observed for total height, unforked height and basal diameter and stem straightness in 63 progenies of Dalbergia sissoo at the age of 15 months after transplanting. Heritability estimates in broad sense as well as genetic advance were high for all the characters under study. Heritability estimates in narrow sense by parents-offspring regression method were also high for straightness and unforked height. Five progenies of plus trees viz. PT28 and PT12 from Haldwani, PT283 from Gonda, PT84 from Nepal and PT9 from Tanakpur were found most promising for straightness, basal diameter, total height and unforked height. Progenies of PT27 and PT25 from Haldwani, PT80 from Sirsa, PT8 from Tanakpur and PT56 from Fatehpur were also found superior for most of the characters. Progenies of plus trees from Haldwani, Tanakpur and Sirsa were in general found promising. Progenies of plus trees viz., PT28, PT12, PT27, PT22 and PT25 from Haldwani, PT9 and PT8 from Tanakpur, PT283 from Gonda, PT84 from Nepal, PT80 from Sirsa arid PT56 from Fatehpur showed consistently superior performance starting from nursery up to 15 months after transplanting in the field.