scholarly journals Selection Approaches in High-Elevation Coastal Douglas-fir in The Presence of GxE Interactions

2011 ◽  
Vol 60 (1-6) ◽  
pp. 79-84 ◽  
Author(s):  
M. Stoehr ◽  
J. Woods ◽  
A. Yanchuk

Abstract Regeneration obligations in British Columbia for high-elevation coastal sites requires a secure seed supply of quality seed in coastal Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco). Consequently, a seed orchard is under development to supply seed after genetic testing and selection. For this purpose, 55 coastal Douglas-fir families were field-tested for 11 years on two contrasting high-elevation sites to examine differential growth performance and tolerance to cold conditions. Although heritabilities for growth on both sites were moderate at age 11, the higher elevation colder site had substantially slower growth and over 90% of the trees exhibited some form of cold damage to foliage, branches and stems; however, variation in this damage was not significant at the family level. Combined site analysis revealed a highly significant genotype by environment (GxE) component in height that could not be removed or reduced by using site-specific error variances or spatial analysis (i.e., GxE was primarily due to rank changes of families across the two sites). This was also reflected by a drop in heritability estimates obtained from the combined site analyses. In the presence of this type of GxE, independent culling, considering height a separate trait on each site, was employed to identify parents that were at a threshold breeding value of 5% or greater in growth superiority on both sites. Average breeding values for the selected parents, based on a combined site analysis, were around 5% above the trial mean for height at age 11. The use of independent culling, for situations where accurate genetic parameters are difficult to obtain, should be considered a practical alternative to more complex and error prone methods of selection.

2016 ◽  
Vol 52 ◽  
pp. 82-94 ◽  
Author(s):  
A. Ye. Pochukalin

One of the ways of increasing level of animal economically useful traits is selection work with farm families. In pedigree cattle breeding of Ukraine families are a statistical component of breed genealogy. Among the main scientific works on working with families, it should be noted minimum number of female ancestors, proposed by D. T. Vinnichuk, to determine the breeding value, different categories, classification and techniques for evaluating related groups of females. The aim of our research was to analyse importance of farm families for genealogical structure of the breed. The research was on basis of data of primary breeding records at the herd of Volyn Beef cattle of “Zorya” breeding farm, Kovel district, Volyn region. Akula 102, Galka 37 and Galka 1537 families belonging to Krasavchyk 3004 bloodline, Smorodyna 613, Korona 2382 and Visla 1016 families – Tsebryk 3888 bloodline, Kalyna 212, Verba 1536 and Garna 536 families – Yamb 3066 bloodlines, Kazka 433, Galka 421 and Bystra 1124 families – Buinyi 3042 bloodline, Rozetka 1313, Arfa 599 and Bulana 943 families – Sonnyi-Kaktus 3307-9828 bloodline, and Palma 275, Desna 870 and Veselka 444 families – Mudryi 9100 bloodline were characterized. Belonging to a bloodline was determined by the father's side of female ancestors. Structural units of families: branches, branching with identifying the best individuals on breeding traits were submitted to identify the best combinations and successful use of closely related breeding. Comparing assessment of related groups of females on the main breeding traits belonging to Krasavchyk 3004 bloodline, it was noted that the cows of Akula 102 family predominated in live weight at 5 years’ age, milk ability and economic use duration, whereas the cows of Galka 1537 family – on traits of reproductive ability. Smorodyna 613 family of Tsebryk 3888 bloodline had high duration of economic use and cows’ live weight at 5 years’ age compared with Korana 2382 and Visla 1016 families with equal values of the exterior traits (height measures) and coefficient of reproductive ability. The families of Mudryi 9100 bloodline in terms of reproduction (calving interval, coefficient of reproductive ability) had the highest figures of cows’ milk ability and live weight. The cows of Bulana 943 family had a considerable predominance over representatives of Rozetka 1313 and Arfa 599 families of Sonnyi-Kaktus 3307-9828 bloodline by main economically useful traits. High indices of reproductive ability were noted in these families. Heifers of the families of Buinyi 3042 bloodline had high live weight at 18 months’ age at average values of milk ability and cows’ live weight at 5 years’ age. More equal figures of growth rate, exterior and economic use duration were observed in the cows of Kalyna 212, Verba 1536 and Garna 536 families of Yamb 3066 bloodline. Breeding by families in beef cattle breeding is an important element of selection, because it allows to evaluate not only related group of female ancestor, but also to analyse a successful combination with lines and purposeful use of closely related breeding by the best representatives of a breed.


Zootaxa ◽  
2007 ◽  
Vol 1645 (1) ◽  
pp. 35-45 ◽  
Author(s):  
DAVID C. LEES ◽  
JONAS R. STONIS

The family Tischeriidae is recorded from Madagascar for the first time. Coptotriche alavelona Lees and Stonis, sp. n., is described from high elevation tropical moist forest of Madagascar, and its proposed generic placement discussed. DNA of this species has been extracted and conserved for future phylogenetic or barcoding studies. The external features and male genitalia are figured and described. An updated checklist and a distribution map for all 13 Tischeriidae species currently recorded from the Afrotropics are provided.


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.


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 ◽  
...  

2010 ◽  
Vol 40 (1) ◽  
pp. 155-166 ◽  
Author(s):  
M. G. Cruickshank ◽  
B. Jaquish ◽  
A. F.L. Nemec

The objectives of this study were to (i) develop a methodology for screening conifer seedlings for resistance to Armillaria ostoyae (Romagn.) Herink and (ii) screen a population of interior Douglas-fir ( Pseudotsuga menziesii var. glauca (Biessn.) Franco) population for resistance to A. ostoyae. Eighteen potted seedlings from each of 86 half-sib interior Douglas-fir families were challenged with inoculum in a 3-year greenhouse trial. The seed originated from four geographically distinct tree breeding zones that represent physically and biologically different environments in southeastern British Columbia. Mortality and the final percent survival of inoculated trees showed differences among the families (survival range 0%–61.1%) and breeding zones (survival range 6.6%–25.3%). Maximum heritability index (0.19) occurred at 28 months. Survival analyses revealed that most of the differences in survival could be explained by the zone from which the family originated. The less susceptible seedlings originated from the drier and warmer zones and limited the spread of the fungus in the root system. Moderate levels of family variation in resistance to A. ostoyae and low-moderate heritability suggest that, in interior Douglas-fir, gains in resistance can be achieved through breeding.


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