Seed Losses to Feeding by Leptoglossus occidentalis (Heteroptera: Coreidae) During Two Periods of Second-Year Cone Development in Western White Pine

1991 ◽  
Vol 84 (1) ◽  
pp. 215-217 ◽  
Author(s):  
A. E. Connelly ◽  
T. D. Schowalter
1976 ◽  
Vol 6 (1) ◽  
pp. 6-12 ◽  
Author(s):  
S. Eis

Twenty-one-year records of western white pine cone counts were analyzed with seven meteorological variables to find if any combinations of available weather factors were associated with the induction of reproductive buds and successful development of the strobili. The weather in three periods before the physical initiation of the potentially reproductive cycle showed association with cone counts: (1) sunny weather in June, 39 months before cone maturation; (2) warm, sunny, dry weather in September and October, 36 and 35 months before cone maturation; and (3) warm, sunny, dry weather with wide daily temperature range in June and July, 27 and 26 months before cone maturation, appeared to promote differentiation of potentially reproductive buds. During and after the initiation of bud primordia, the weather in four periods appeared to be associated with cone production: (1) warm and possibly wet weather in August, September, and October, 25 to 23 months before cone maturation; (2) rain in the third quarter of July, 4 weeks after pollination and 14 months before cone maturation; (3) warm temperatures in September, October, and November, 12 to 10 months before cone maturation; and (4) sunny, warm, dry weather in May, 4 months before cone maturation, appeared to be beneficial to cone development.


2007 ◽  
Vol 37 (2) ◽  
pp. 260-275 ◽  
Author(s):  
John N. Owens ◽  
Danilo D. Fernando

The reproductive biology of western white pine ( Pinus monticola Dougl. ex D. Don) at the Saanich seed orchard (SSO; a coastal seedling seed orchard) and the Kalamalka seed orchard (KSO; an interior clonal seed orchard) is described. Seed-cone development and morphology determine seed potential and affect filled seed production. Seed potential was high, commonly over 200 seeds per cone and filled seeds per cone averaged 50–60 at both orchards in 1999 from open pollinations combined with operational supplemental mass pollinations (OP-SMP). Filled seeds per cone at SSO in 2004 averaged 115 with open pollinations and OP-SMP. About 30% of ovules aborted before pollination. Another 25% aborted probably because of self-incompatibility at fertilization. Seed efficiency (SEF) was only 5% at KSO with open pollination but increased to 30% with OP-SMP. SEF was the same at SSO with or without OP-SMP. Reproductive success was very low at KSO without OP-SMP but increased to about 10%, similar to that of SSO, with OP-SMP. The optimal time for control pollinations was at cone stages 4 and 5 and optimal amount of pollen per pollination bag was 0.3–0.4 mL. Western white pine is a very good seed producer and can be easily managed in seed orchards to give very high seed production per cone and per tree.


Author(s):  
Darla Bruns ◽  
John N. Owens

The chloroplast genome is predominantly paternally-inherited in conifers whereas mitochondria may be maternally-inherited. Molecular approaches do not reveal the mechanisms by which this is achieved. A recent study of mechanisms of organelle inheritance in Pseudotsuga menziesii has complimented earlier work on fertilization in conifers by demonstrating that, in the archegonium prior to syngamy, maternal plastids are transformed into large inclusions and mitochondria concentrate in a perinuclear zone. Paternal plastids and mitochondria are transferred with the male gametes and contribute to proembryo formation. In the present study, male and female gametophyte development, fertilization and proembryo development were examined inPinus monticola to determine mechanisms of plastid and mitochondrial inheritance.Second year female cones were collected from mid-April to mid-June in 1987 and 1988 from trees growing in Victoria, B.C., Canada. Ovules were removed and median portions dissected out and fixed under vacuum for 2h-overnight in cold 2.5% glutaraldehyde and 2% formaldehyde in 50 mM P-buffer, pH 7.2. Tissues were buffer-washed for lh, post-fixed in 1% buffered OsO4 for lh and buffer-washed overnight. Dehydration in a graded acetone series preceded infiltration in low viscosity resin and then 60-70 nm sections were cut on a Sorvall MT5000 ultramicrotome using a diamond knife. Sections were collected on uncoated mesh or formvar-coated notchdot grids, stained with uranyl acetate and lead citrate and examined on a Phillips EM300 at 60 kV or JOEL JEM-1200EX at 60 kV.


1965 ◽  
Vol 43 (12) ◽  
pp. 1553-1559 ◽  
Author(s):  
S. Eis ◽  
E. H. Garman ◽  
L. F. Ebell

Cone count records for a 28-year period on 80 Douglas fir, 14 grand fir, and 9 western white pine were statistically analyzed with the annual diameter increment to evaluate the relationship between cone and wood production. The width of annual rings was depressed only during the years of cone production, suggesting that carbohydrates used in cone development were supplied from current photosynthesis rather than from stored reserve. The initiation of reproductive buds did not appear to be dependent on the level of carbohydrates in a tree and the role of carbohydrates was probably only that of nutrition during cone development. Maturing cones did not exhibit any inhibitory effect on initiation of new flowering buds. Different species may require a different combination of climatic factors for initiation of flowering buds.


1990 ◽  
Vol 122 (5) ◽  
pp. 963-968 ◽  
Author(s):  
Bruce C. Campbell ◽  
Patrick J. Shea

AbstractPectinmethylesterase (PME) activity was found in the salivary glands of nymphs and adults of a leaf-footed bug, Leptoglossus occidentalis Heidemann. Puncture wounds in cone scales resulting from PME activity in the saliva of these bugs were seen by staining with a 0.05% aqueous solution of ruthenium red. This staining technique can be used to estimate feeding damage by L. occidentalis on cones of western white pine (Pinus monticola Dougl.), sugar pine (P. lambertiana Dougl.), and Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco).


1994 ◽  
Vol 126 (1) ◽  
pp. 1-5 ◽  
Author(s):  
N.G. Rappaport ◽  
M.I. Haverty ◽  
P.J. Shea ◽  
R.E. Sandquist

AbstractWe tested the pyrethroid insecticide esfenvalerate in single, double, and triple applications for control of insects affecting seed production of blister rust-resistant western white pine, Pinus monticola Douglas. All treatments increased the proportion of normal seed produced and reduced the proportion of seed damaged by the western conifer seed bug, Leptoglossus occidentalis Heidemann. Only the triple application reduced the proportion of cones killed by the pine cone beetle, Conophthorus ponderosae Hopkins. Other seed-damaging insect species [seed chalcids, Megastigmus sp.; the fir coneworm, Dioryctria abietivorella (Grote); and seedworms, Cydia sp.] were present but in numbers too low to test for insecticide efficacy.


2002 ◽  
Vol 32 (7) ◽  
pp. 1109-1125 ◽  
Author(s):  
Theresa B Jain ◽  
Russell T Graham ◽  
Penelope Morgan

Many studies have assessed tree development beneath canopies in forest ecosystems, but results are seldom placed within the context of broad-scale biophysical factors. Mapped landscape characteristics for three watersheds, located within the Coeur d'Alene River basin in northern Idaho, were integrated to create a spatial hierarchy reflecting biophysical factors that influence western white pine (Pinus monticola Dougl. ex D. Don) development under a range of canopy openings. The hierarchy included canopy opening, landtype, geological feature, and weathering. Interactions and individual-scale contributions were identified using stepwise log–linear regression. The resulting models explained 68% of the variation for estimating western white pine basal diameter and 64% for estimating height. Interactions among spatial scales explained up to 13% of this variation and better described vegetation response than any single spatial scale. A hierarchical approach based on biophysical attributes is an excellent method for studying plant and environment interactions.


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