GROWTH OF TRIPLOID ACACIA HYBRID CLONES IN CLONAL TRIALS IN BAC GIANG AND QUANG TRI PROVINCES, VIETNAM

Abstract

The rapid expansion of domestic plantation scale in recent years has resulted in acacia forests facing a high risk of disease, especially wilt disease (Ceratocystis sp.) and pink disease (Corticium salmonicolor). For that reason, acacia breeding programs need to be carried out to create new varieties in order to reduce the risks of acacia plantations. The objective of the study was to select triploid acacia hybrid clones with fast growth and good stem form for commercial planting. The study was conducted on two clonal trials at Yen The district, Bac Giang province and Cam Lo district, Quang Tri province, which included newly selected clones and some commercial clones as controls. The growth evaluation was carried out in 2 clone trials at Yen The at 62 months of age and at Cam Lo was at 57 months of age. At Yen The: there were significant differences between the growth as well as stem quality, but there is no difference in survival. The diameter average of the trial was 12,27 cm, the height and the volume were 14.17 m and 113.20 dm³/tree respectively; clones X201, X205, X102, X101 and X801 had the MAI from 21.60 to 28.38 m³/ha/year, reaching the highest yield with the other in the trial. Moreover, these clones had the MAI also larger or equivalent compared to control varieties such as BV10 and BV16. At Cam Lo, survival overall was 69.60%; the diameter, the height and the volume were 9.63 cm, 12.24 m and 53.50 dm³/tree respectively; significant differences between clones were observed in growth traits and stem quality. There are five clones which had the highest MAI in the trial (X201, X801, X102, X1117, X1141). The results of this research is really essential, contribute to enhance the economic efficiency and sustainable development of forest resources in the future