Influence of phosphorus on growth and wood basic density of Pinus massoniana provenances

Key words: 
• forest tree breeding /
• Pinus massoniana /
• provenance /
• phosphorus /
• growth /
• wood basic density （WBD） /
• interaction

Abstract: In order to select optimal combination of provenance and phosphorus level for pulp wood and saw timber，a 12-year-old Pinus massoniana （masson pine） trial was used to reveal the main effect and interaction of three phosphorus levels （0，100 and 400 gtree－1） and five provenances （Wuping of Fujian，Gaozhou of Guangdong，Xinyi of Guangdong，Cenxi of Guangxi，and Chongyi of Jiangxi） on growth，stem-form qualities，and wood basic density （WBD）. A randomized complete design with four blocks of twenty-eight trees per plot was used and selected 6 to 8 trees inside every plot. Variance analysis was done using GLM program in SAS sofeware. Results indicated that growth and WBD were not significant difference （P＞0.01） for Wuping between three phosphorus levels，suggesting Wuping an excellent provenance with tolerance to low phosphorus. Gaozhou was significant increasing for growth with phosphorus level higher，and had a long duration to phosphorus. In the condition of phosphorus not supplied，Wuping had the significant largest （P＜0.05） diameter at breast height （DBH） and height and was superior to the other provenances，whereas Chongyi was the worst，lower 19.8% and 12.7% for DBH and height than Wuping. Provenances from Gaozhou，Xinyi，Cenxi，and Chongyi had the best fertilizer efficiency；however，with Wuping differences decreased when phosphorus level were 100 and 400 gtree－1. For WBD Chongyi was considerabley lower （P＜0.05） than the other provenances under 0 gtree－1 phosphorus level. The experiment also showed that provenance by phosphorus interaction was significant for height （P＜0.01） and WBD （P＜0.05）. Based on the main effects and interactions，optimal combinations of Wuping under 0 gtree-1 phosphorus level，and Gaozhou under 100 gtree－1 phosphorus level were selected for pulpwood and sawtimber，repectively.［Ch，1 fig. 4 tab. 21 ref.］