Lodgepole pine (Pinus contorta var. latifolia) is the most wide-ranging pine in North
America. Populations in British Columbia vary widely in phenotypic and genotypic
characteristics. The effect of climate on variation in reproductive characteristics has never
been examined, yet is vital to the production of seed necessary for reforestation. This
study aims to determine the relationship between the climate in B.C and variation in
female cone and seed characteristics.
The study makes use of the Illingworth provenance trial, sixty common garden plots
that are distributed throughout British Columbia. Female cones from six provenances
were collected at 21 sites during the summer of 2012. The number of scales was counted
and maximum length was measured for each cone. Seed was extracted and counted.
Variables were pooled for each tree. The climate at each site was described using data
from ClimateWNA. Principal components analysis was used to reduce the highly
correlated data set to the first two principal components (PC1 and PC2), which together
described 76.7% of the variation in the data. PC1 was most closely aligned with variables
related to temperature, the number of frost-free days, and degree-days above 5°C or
below 0°C. PC2 was most closely aligned with precipitation and moisture variables.
The reproductive variables were moderately positively correlated with one another.
Analysis of variance indicated that average cone length and the average number of seeds
per cone were significantly affected by both site and provenance, however the average
number of seeds per cone was not. Average values of each reproductive trait for each site
were modelled against the first two principal components using multiple analysis of
variance and univariate linear modelling. The best-fit model for the average number of
scales per cone included PC1 and PC2, however the model only described 4.9% of the
variation in the data. The best-fit model for the number of seeds included only PC1, and
iv
the model only explained 4.1% of the variation in the data. The model for average cone
length had the strongest results, with a model that included PC2 and explained 18.7% of
the data.
The results of the study indicate that climate is not the most important factor in
predicting reproductive characteristics such as cone length, and the number of scales and
seed per cone. The significant effect of moisture on average cone length was the strongest
relationship identified in the study. The reproductive traits were best described by their
stability across the climates of the test sites. High genetic variation in lodgepole pine
populations may be contributing to the stability of reproductive traits. Lodgepole pine
female cone and seed traits were stable for mature trees over a wide range of provenances
and climate regions. / Graduate / 0309 / 0478 / anne.berland@gmail.com
Identifer | oai:union.ndltd.org:uvic.ca/oai:dspace.library.uvic.ca:1828/5151 |
Date | 09 January 2014 |
Creators | Berland, Anne |
Contributors | Aderkas, P. von, Anholt, Bradley Ralph |
Source Sets | University of Victoria |
Language | English |
Detected Language | English |
Type | Thesis |
Rights | Available to the World Wide Web |
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