tailieunhanh - Báo cáo khoa học: "Branch architecture QTL for Pinus elliottii var. elliottii × Pinus caribaea var. hondurensis hybrid"

Tuyển tập các báo cáo nghiên cứu về lâm nghiệp được đăng trên tạp chí lâm nghiệp quốc tế đề tài: Branch architecture QTL for Pinus elliottii var. elliottii × Pinus caribaea var. hondurensis hybrids. | Ann. For. Sci. 59 2002 617-625 INRA EDP Sciences 2002 DOI forest 2002047 617 Original article Branch architecture QTL for Pinus elliottii var. elliottii X Pinus caribaea var. hondurensis hybrids Mervyn Shepherda Michael Crossa Mark J. Dietersb and Robert Henrya Cooperative Research Centre for Sustainable Production Forestry Centre for Plant Conservation Genetics Southern Cross University PO Box 157 Lismore NSW Australia b Cooperative Research Centre for Sustainable Production Forestry Queensland Forestry Research Institute Gympie QLD Australia Received 5 July 2001 accepted 11 February 2002 Abstract - Putative quantitative trait loci QTL of moderate additive effect were identified for branch diameter average number of branches per whorl per tree average whorl spacing and regularity of whorl spacing in a single Pinus elliottii var. elliottii X P. caribaea var. hondurensis family. There was no evidence of additive X additive epistasis or pleiotropy. No marker-trait associations were detected for the average branch angle per whorl per tree. The detection of gene effects that were seemingly larger but less numerous than those expected for traits with low to moderate heritabilities was attributed to bias in the estimation of QTL magnitude and limited power to detect QTL due to a small sample size. Branch architecture traits exhibited considerable variation within the family with ranges of 4-6 standard deviations SD and tended to be less variable than height and diameter. Branching characters were largely independent of one another as well as growth form and wood density properties. Branching characters other than branch angle were not influenced by macro-environmental factors. genetic mapping branch angle branch diameter whorl spacing whorl regularity Résumé - QTL concernant l architecture de la branchaison chez les hybrides entre Pinus elliottii var. elliottii Pinus caribaea var. hondu-rensi. On a identifie des QTL qui semblent avoir un effet modéré et additif .