Tree Improvement Program Project Report 2006 / 2007

.2.1 Conduct ng a Ser es of So l
Tests n the Kalamalka Larch
Seed Orchards to obta n a
Basel ne Ind cat on of the Levels
of Pythium and Fusarium
(SPU 1303)
Gary G ampa
Object ves
In 2005 Kalamalka lost almost five percent of the ramets
in our larch seed orchards. The trees were either very
productive mature ramets or new transplants with a high
breeding value. An investigation by Michael Peterson
of Applied Forest Sciences indicated the possibility that
pathogen levels in the soil were high enough to cause
a disease threat. If we can determine levels of Pythium
and Fusarium present in the orchards, our management
techniques can be modified to maximise ramet survival and
maintain seed production levels.
Act v t es
In order to obtain a baseline indication of the levels of
Pythium and Fusarium, we made a series of soil tests in
transects across the seed orchards. The samples were then
analysed for pathogens. The samples were collected in the
spring, summer, and fall of 2006.
Results
These tests indicated that levels of soil-borne Pythium and
Fusarium fungi in both Kalamalka larch seed orchards were
significantly higher than levels that are commonly believed
to lead to disease conditions.
spring summer fall
Pythium
propagules
per gram
average 1834 5545 2271
Fusarium
propagules
per gram
average 3458 9033 3047
Table 23.
T R E E I M P R O V E M E N T P R O G R A M
P R O J E C T R E P O R T 2 0 0 6 / 2 0 0 7
Output and del verables
It is impossible to state conclusively that these high
pathogen levels are causing the mortality in the Kalamalka
larch orchards, but the levels are a concern. In 2007 we
intend to test several different irrigation regimes in our
larch orchards in an effort to reduce these high levels of
harmful pathogens. We will collect and analyse soil samples
to determine the response of the Pythium and Fusarium
fungi to various watering treatments.
.2.1 Collect on of Crop Stat st cs
for Inter or Lodgepole P ne
Orchards
Prepared for M chael Carlson by Joe Webber,
ProSeed Consult ng
The Lodgepole Pine Task Force met on January 25, 2006
(VSOC) and determined the need to develop methodology
for making comparisons among producing lodgepole
pine seed orchards. The underlying concern is that seed
production from north Okanagan orchards is significantly
less than expected. To determine the source of these losses
and make recommendations for orchard management
practices to improve seed production, the task force
required standardized collection of data for all producing
orchards. This project developed standard methods for
estimating the number of cones per tree based on cone
weight, and for estimating cone yields (filled seed per cone,
total seed per cone, seed weight), pollen cloud density,
and seed losses from insect predation. As these data are
collected over several years, trends in yearly variation in
cone numbers and seed yields will help determine why seed
set in the north Okanagan lodgepole pine seed orchards is
chronically low. A summary of the methodology and results
for OTIP project 0722 follows. A detailed final report for
SPU 0722 (2006) is available from the OTIP coordinator.
In the spring of 2006, 15 trees (clones) were selected
to include both early, mid- and late-flowering clones. The
number of cones per tree was estimated by weighing a
known number of cones and the total number of cones
per tree. This method removed a source of error that
resulted from estimating cone numbers per tree by volume.
Figure 59 shows the data for the 15 selected trees (+/-
9