Graduate Thesis Or Dissertation
 

Variation in adaptive traits of coastal Douglas-fir : genetic and environmental components

公开 Deposited

可下载的内容

下载PDF文件
https://ir.library.oregonstate.edu/concern/graduate_thesis_or_dissertations/q237hv18b

Descriptions

Attribute NameValues
Creator
Abstract
  • Cold hardiness and phenology are important adaptive traits for perennial plant species in temperate climates. Timing of growth, dormancy, and associated cold acclimation and deacclimation represents a delicate balance between maximizing growth under favorable conditions and minimizing frost damage under unfavorable conditions. Geographic patterns of genetic variation in adaptive traits, such as cold hardiness and bud phenology, are complex in coastal Douglas-fir populations (Pseudotsuga menziesii var. menziesii (Mirb.) Franco) and correspond to the heterogeneity of environments in mountainous terrain (Campbell and Sorenson 1973, Rehfeldt 1986, Loopstra and Adams 1989). In order to assess the adaptive significance of cold hardiness and bud phenology traits within Douglas-fir breeding populations (breeding zones) and the ability of traditional progeny tests to reveal genetic variation in these traits, this study investigated the relationship between family variation in these adaptive traits and 1) characteristics of parent tree environments, and 2) environmental variables of test sites. Forty families (6 to 7 year old trees) from each of two breeding zones (central Oregon Coast and Cascade ranges) were assessed for several cold hardiness and phenological traits over a two year period. Variation among traits was summarized through principal components analysis. Family means for the first five principal components (PC's) from each population, as well as univariate traits representing fall and spring cold damage and height, were regressed on geographic and topographic variables, as well as on climatic indices of parent tree locations. Despite the small size of the breeding zones, PC's of parent trees in both zones were significantly related to location and climatic variables. In the coastal zone, PC-1 (explaining 46% of trait variation and primarily a function of spring phenology and hardiness) was related to both temperature and moisture variables, climatic factors that vary along gradients of elevation and distance from the ocean. In the Cascade zone, only very weak relationships exist between PC- 1 (explaining 39% of trait variation) and parent-tree variables. PC-2 (primarily a function of fall cold hardiness, explaining 22% of the variation in the coastal zone and 20% of the variation in the Cascades zone) was significantly related to temperature and moisture in both breeding zones. Despite notable variation in climate between the two test years and two test sites within each breeding zone, the first two PC'S were very consistent in both breeding zones demonstrating that adaptive trait patterns are stable across test environments and years. To assess the ability of progeny tests to reveal genetic variation in phenology and cold hardiness traits, individual tree values for these traits were related to topographic factors in two test sites selected for their environmental heterogeneity. Analyses of variance of single adaptive traits for each site (consisting of traditional randomized complete blocks and multiple-tree non-contiguous plots) were conducted with and without topographic factors included as covariates. The influence of within-block topographic variation on the ability to detect family differences was evaluated by comparing heritability estimates for the alternative analyses. Selected covariates were predominantly topographic factors affecting temperature and moisture regimes of individual trees. In one site (located on a steep slope) elevation was the predominant factor affecting expression of cold hardiness; in the second site these traits were primarily influenced by frost pockets. Covariate adjustments for either factor had little effect in improving the precision of genetic estimates. Thus, on each site the traditional experimental design and analysis was adequate for dealing with microtopographic variation.
Resource Type
Date Available
Date Issued
Degree Level
Degree Name
Degree Field
Degree Grantor
Commencement Year
Advisor
Committee Member
Academic Affiliation
Non-Academic Affiliation
Subject
权利声明
Publisher
Peer Reviewed
Language
Digitization Specifications
  • PDF derivative scanned at 300 ppi (256 B&W), using Capture Perfect 3.0.82, on a Canon DR-9080C. CVista PdfCompressor 4.0 was used for pdf compression and textual OCR.
Replaces

关联

Parents:

This work has no parents.

属于 Collection:

单件

缩略图 标题 上传日期 公开度 行动
file details BaldumanLisaM1995.pdf 2017-08-07 公开 下载