Mating success in a coastal Douglas-fir seed orchard as affected by distance and floral phenology

1989 ◽  
Vol 19 (10) ◽  
pp. 1248-1255 ◽  
Author(s):  
V. J. Erickson ◽  
W. T. Adams

The effect of distance and stage of phenological development on cross-pollination in a Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) seed orchard was investigated by estimating the proportion of viable embryos resulting from fertilization by designated male trees. The pollen source was identified by unique allozyme genetic markers that occurred in two clones in the orchard. In 38 mother trees, the proportion of embryos fertilized by the male marker ranged from 0 to 71.4%. Very little pollen was dispersed beyond 30 m. Within 30 m, mating success was only weakly associated with distance. Multiple regression analyses determined that phenological factors strongly influenced mating patterns; nearly one-third of the variation was dependent on a phenological variable (LMmf), which measured the combined effects of floral overlap and relative pollen fecundity of potential male parents. The interaction between LMmf and distance was highly significant, indicating that the floral status of mating pairs had a strong influence on the effect of distance. Our results suggest that a lack of complete floral synchrony between near neighbors may reduce preferential mating and thus help to promote cross-fertilization within Douglas-fir seed orchards.

2005 ◽  
Vol 35 (7) ◽  
pp. 1592-1603 ◽  
Author(s):  
Gancho T Slavov ◽  
Glenn T Howe ◽  
W Thomas Adams

Pollen contamination is detrimental to the genetic quality of seed orchard crops. Highly variable simple sequence repeat (SSR) markers make it possible to accurately measure pollen contamination and characterize patterns of within-orchard mating by directly identifying the male and female parent of each seed produced in the orchard. We used nine SSR markers to measure pollen contamination and characterize mating patterns based on seed samples collected in 3 years (1999, 2000, and 2003) from one block of a nonisolated, open-pollinated, clonal seed orchard of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) in western Oregon. Pollen contamination was consistently high across the 3 years (mean = 35.3%, range = 31.0%-41.3%) and appeared to result primarily from cross-pollination among the orchard blocks. Levels of pollen contamination varied substantially among clones and were higher in clones with early female receptivity (mean = 55.5%) than in those with either mid (mean = 36.4%) or late (mean = 28.3%) female receptivity. We detected low rates of self-pollination (mean = 1.8% per clone) and over 10-fold differences in the relative paternal contributions of the clones. There was a clear pattern of positive assortative mating with respect to floral phenology. This study illustrates that SSR markers are powerful tools for characterizing seed lots and improving the design and management of Douglas-fir seed orchards.


1990 ◽  
Vol 20 (10) ◽  
pp. 1672-1675 ◽  
Author(s):  
V. J. Erickson ◽  
W. T. Adams

Proportions of outcrossed progeny (ti) in five ramets of five clones with variable floral phenology and pollen production were investigated in a Douglas-fir (Pseudotsugamenziesii var. menziesii (Mirb.) Franco) seed orchard. Estimates of ti[Formula: see text] were significantly heterogeneous among the five ramets, ranging in value from 0.50 to 1.07. Variation in [Formula: see text] corresponded well with variation among ramets in floral biology. Ramets that flowered much earlier than other individuals in the orchard and (or) had a high degree of synchrony in timing of male and female flowering produced the lowest [Formula: see text].


New Forests ◽  
2009 ◽  
Vol 39 (3) ◽  
pp. 261-273 ◽  
Author(s):  
Yoshinari Moriguchi ◽  
Yoko Yamazaki ◽  
Hideaki Taira ◽  
Yoshihiko Tsumura

1996 ◽  
Vol 1996 ◽  
pp. 50-50
Author(s):  
C.S. Haley

Naturally occurring genetic variation is the basis for differences in performance and appearance between and within different breeds and lines of livestock. In a few instances (e.g. coat colour, polling) the genes (or loci) which control the variation between animals and breeds have a large enough effect to be individually recognisable. For many traits, however, the combined effects of many different genes act together to control quantitative differences between breeds and individuals within breeds (hence such genes are often referred to as quantitative trait loci or QTLs). Thus the dramatic successes of modern breeding result from generations of selection which has produced accumulated changes at a number of different loci. The genome contains up to 100,000 different genes and identifying those which contribute to variation in traits of interest is a difficult task. One first step is to identify regions of the genome containing loci of potential interest through their linkage to genetic markers.


2008 ◽  
Vol 65 (7) ◽  
pp. 706-706 ◽  
Author(s):  
Lúcia Fernandes ◽  
Margarida Rocheta ◽  
Jorge Cordeiro ◽  
Sandra Pereira ◽  
Sophie Gerber ◽  
...  

1996 ◽  
Vol 11 (2) ◽  
pp. 62-69 ◽  
Author(s):  
Brian E. Roth ◽  
Michael Newton

Abstract The goal of this study was to quantitatively evaluate the individual and interactive effects of weed control, nitrogen fertilization, and seed source on Douglas-fir (Pseudotsuga menziesii) survival and growth in a range of sites and growing conditions in western Oregon. Weed control was the dominant factor influencing seedling survival and growth and accounted for 49% of the explained variation in seedling volume after 2 yr. Nitrogen fertilization had no effect when used in conjunction with weed control and a negative effect when used without weed control. Seedlings from a seed orchard source were significantly larger in diameter and volume than those from a wild local source after two growing seasons, but second-year heights were similar for the two seedling types. Initial seedling size was positively correlated with growth rate. West. J. Appl. For. 11(2):00-00.


1982 ◽  
Vol 12 (2) ◽  
pp. 403-408 ◽  
Author(s):  
W. T. Adams

The mean number of pollen grains produced per pollen cone (P) ranged from 37 310 to 62 960 ([Formula: see text], SE = 1584) among eight seed-orchard clones of Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) and correlated significantly (r = 0.87, p < 0.05) with the mean number of microsporophylls per cone but not significantly with pollen cone length. The number of pollen grains per milligram (G) also differed among clones (range 2323–3112; [Formula: see text], SE = 32) and correlated significantly and negatively (r = −0.86) with grain diameter. Although this study provides evidence for genetic variation in both P and G, the differences were relatively small. Adjusting pollen-cone counts for P would add little, if any, precision to estimates of pollen production in seed-orchard clones. If balanced clonal representation in pollen mixes is desired, equal weights of pollen would probably suffice for most breeding applications.


2018 ◽  
Vol 8 (1) ◽  
Author(s):  
Jiayin Song ◽  
Blaise Ratcliffe ◽  
Tony Kess ◽  
Ben S. Lai ◽  
Jiří Korecký ◽  
...  

1977 ◽  
Vol 109 (9) ◽  
pp. 1153-1158 ◽  
Author(s):  
J. Wayne Brewer ◽  
J. O’Neal

AbstractThe insecticide acephate (0.5-dimethyl acetyl phosphoramidothioate) was applied at 0.5, 1.0, and 1.5 lb A.I./gal (.058, 0.118, 0.179 kg/l.) in aqueous solution to individual Douglas-fir trees infested with western spruce budworm, Choristoneura occidentalis Freeman, larvae in central Washington using hand held ground application equipment. Application was made when larvae were in the needle mining – bud mining stage at rates ranging from 2.58 to 5.10 gal/acre (3.97 to 7.84 l./ha). For all three concentrations, mortality of larvae inside needles was 94–98% after 1 day compared with a check mortality of 18% and larval mortality inside buds was 99% after 1 day compared with 23% for the check. Regression analyses indicated that defoliation was positively correlated with the number of needles mined the current year and per cent punctured buds, and negatively correlated with larval mortality inside both needles and buds. The data suggest that when applied at the rates used, acephate has some type of systemic action and can provide foliage protection during the year of application.


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