RESEARCH ON SELECTION OF PLUS TREES OF Sindora tonkinensis A. Chev. Ex K. & S. S. LARSEN IN SEVERAL CENTRAL COAST PROVINCES

Abstract

This research was conducted during 2022 - 2023 to select plus trees of Sindora tonkinensis with high wood yield and good trunk quality for afforestation for sawlog supply in several Central coast provinces. An inventory across 5 provinces in Central Vietnam was undertaken, using the scoring method of the individual trees based on critera of growth, stem straightness, branch smallness, and tree health. As a results, 78 plus trees were selected from 134 candidate trees from 5 provinces including Ha Tinh (12 trees), Quang Binh (25 trees), Quang Tri (15 trees), Thua Thien Hue (10 trees) and Quang Nam (16 trees). The plus trees had good growth with diameter at breast height (D_1.3) and tree height (H_vn) ranging from 22.3 - 76.4 cm and 15 - 30 m respectively. The bole height (the length from ground to the first main living branch) ranged from 8.0 - 21.0 m, and accounted for 50.0 - 78.9% of H_vn, canopy diameter rangd from 7.5 - 16.0 m. All plus trees also had high stem productivity and quality with the total score ranging from 13 - 15 points/tree with an average of 14.6 points/tree. Seeds from 78 Sindora tonkinensis plus trees were collected and stored for propagation to build a germplasm collection area combined with variety trialsby the end of 2024, which contributes to the exploitation and development of gene resources of rare plant species in the Central region.