Genotype X Environment Interaction in Florida Sources of Loblolly Pine Across the Lower Coastal Plain of the Southeastern USA

Florida sources of loblolly pine (Pinus taeda L.) have previously been reported to exhibit a high level of genotype x site interaction (GxE) when compared to other sources of loblolly in one set of progeny tests established by the Cooperative Forest Genetics Research Program (CFGRP). This may indicate the need for regionalization of breeding and deployment by separating sites on the coastal plains of the Atlantic and Gulf costs to minimize the level of within-region GxE. The study presented here aimed to elucidate patterns of GxE in Florida loblolly pine utilizing data on individual tree volume at 10-15 years of age collected from a total of 36 tests (27 open-pollinated and 9 control-pollinated tests) established by the CFGRP and its members across a diverse range of sites on the lower coastal plain of the south-eastern 179 USA. These tests were established over a 19-year period from 1970 to 1988 and comprised: five, largely genetically disconnected series of progeny tests; and, progeny from 117 plus-trees selected in a number of Florida counties, but chiefly from the Marion (46), Levy (22) and Nassau (19) counties. Climatic data was collated for each of the test-sites for the period from planting to the age of measurement. This climatic data, along with site characteristics calculated from the growth data (i.e. site index, and rust hazard) were used to classify the environment types represented by the progeny tests. Sites spanned a broad range of environment-types: Greene Co., MS to Levy Co., FL and Laurens Co. GA; site indexes ranging from 15.5 to 37.1m; and, rust hazard varying between 2 and 98%.

Download this file:

Download this file

Details

Author(s): Mark J. Dieters, Dudley A. Huber

Publication: Tree Improvement and Genetics - Southern Forest Tree Improvement Conference - 2007