Assessment of growth and disease index of new acacia hybrid and acacia auriculiformis clones approved in recent yea

Abstract

In recent years, a number of fast-growing Acacia clones was approved by Ministry of Agricuture and Rural Development as new advanced-technological clones. However, approval of these new clones was based on clonal tests established in one or several ecological zones with small scale and only some of these clones were planted in large
scale. In order to put new varieties into large-scale planting, planting trials of these varietes in major ecological regions of Vietnam should be established. Trials of new Acacia clones were conducted in 2010 and 2011 in 5 ecological regions. After two years in Ca Mau and three years in Yen Bai, two Acacia auriculifomis clones AA1 and AA9 achieved a Mean Annual Increment (MAI) of more than 20 m3 /ha/yr. For Acacia hybrids, two clones coded AH1 and AH7 had a MAI of more than 25 m3/ha/yr in trial in Ca Mau and Thanh Hoa, while clone KL2 (two years old) achieved a MAI of 22.3 m3/ha/yr. In all trials, pink disease caused by Corticium salmonicolor and leaf wilted disease caused by Ceratocytis sp. were not found, while leaf spots and twig died-back were found on A26 and AA15 A. auriculifomis clones and TB1, TB11 and TB12 hybrid clones. Hybrid clones AH1 and AH7 as well as A. auriculifomis clones AA1 and AA9 showed great potential in growth performance and disease resistanc