Selection of Yemane (Gmelina arborea Roxb.) Plus Trees in the Philippines

摘要

This paper describes the selection of yemane (Gmelina arborea) plus trees Using point grading method, 24 plus trees (PTs) of yemane were selected at Talacogon, Mindanao, Philippines to collect quality seeds and also to use these PTs as the base for future breeding and tree improvement programmes, Average height of the selected plus trees was 25.50 m and the average height of the comparison trees was 22.75 m. Selection differential for height was 2 75 m (12%). Average diameter of the selected plus trees was 28.50 cm and the average diameter of the comparison trees was 25.25 cm. Selection differential for the diameter was 3.25 cm (13%). Average selection intensity was 1 tree out of 2,284 trees (approx. 1 tree in 4 ha) This is comparatively a high selection intensity. It is recommended that for any future breeding programme with Gmelina arborea, at least 50 plus trees should be included and the selection intensity may be as low as one tree out of 10,000 trees.