Breeding without Breeding: Is a Complete Pedigree Necessary for Efficient Breeding?

Complete pedigree information is a prerequisite for modern breeding and the ranking of parents and offspring for selection and deployment decisions. DNA fingerprinting and pedigree reconstruction can substitute for artificial matings, by allowing parentage delineation of naturally produced offspring. Here, we report on the efficacy of a breeding concept called “Breeding without Breeding” (BwB) that circumvents artificial matings, focusing instead on a subset of randomly sampled, maternally known but paternally unknown offspring to delineate their paternal parentage. We then generate the information needed to rank those offspring and their paternal parents, using a combination of complete (full-sib: FS) and incomplete (half-sib: HS) analyses of the constructed pedigrees. Using a random sample of wind-pollinated offspring from 15 females (seed donors), growing in a 41-parent western larch population, BwB is evaluated and compared to two commonly used testing methods that rely on either incomplete (maternal half-sib, open-pollinated: OP) or complete (FS) pedigree designs. BwB produced results superior to those from the incomplete design and virtually identical to those from the complete pedigree methods. The combined use of complete and incomplete pedigree information permitted evaluating all parents, both maternal and paternal, as well as all offspring, a result that could not have been accomplished with either the OP or FS methods alone. We also discuss the optimum experimental setting, in terms of the proportion of fingerprinted offspring, the size of the assembled maternal and paternal half-sib families, the role of external gene flow, and selfing, as well as the number of parents that could be realistically tested with BwB

Testowanie potomstwa hybrydowego i różnych gatunków rodzaju Abies dla leśnictwa, ogrodnictwa ozdobnego oraz produkcji choinek

The paper evaluated dendrometric parameters of hybrid progenies of various Abies species obtained during measurements in the spring 2010 on the research plot in Kostelec nad ýernými lesy. Data were processed and compared to the measurement taken in 2004. Results show that all hybrid progenies within the plot exceeded A. alba in investigated parameters. Only two of the progenies achieved worse results in mean height – A. koreana × (A. cilicica × A. cephalonica) and progeny of spontaneous hybrid no. 2. Considering height and diameter A. nordmanniana was evaluated as the most productive. On the contrary A. gracilis is considered unsuitable for further culture and research due to the mortality of 100%.Niniejsza praca ocenia parametry dendrometryczne hybrydowego potomstwa różnych gatunków Abies otrzymane podczas pomiarów wiosną 2010 na poletku doświadczalnym w Kostelec nad Černými lesy. Otrzymane dane były przetworzone i porównane z pomiarami poczynionymi w roku 2004. Wyniki pokazują, że całe potomstwo hybrydowe na poletku przewyższało A. alba pod względem badanych parametrów. Tylko dwa osiągnęły gorsze rezultaty, jeśli chodzi o średnią wysokość – A. koreana × (A. cilicica × A. cephalonica) oraz potomek spontanicznej krzyżówki no. 2. Pod względem wysokości i średnicy, A. nordmanniana oceniono jako najbardziej produktywną. Z kolei A. gracilis uważa się za nieodpowiednią do dalszej uprawy i badań ze względu na 100% śmiertelnoś

Positive Assortative Mating With Family Size as a Function of Predicted Parental Breeding Values

While other investigations have described benefits of positive assortative mating (PAM) for forest tree breeding, the allocation of resources among mates in these studies was either equal or varied, using schemes corresponding only to parental rank (i.e., more resources invested in higher-ranking parents). In this simulation study, family sizes were proportional to predicted midparent BLUP values. The distribution of midparent BLUP values was standardized by a constant, which was varied to study the range of distributions of family size. Redistributing progenies from lower- to higher-ranking families to a point where an equal number of progenies were still selected out of each family to the next generation caused minimal change in group coancestry and inbreeding in the breeding population (BP), while the additive genetic response and variance in the BP were both greatly enhanced. This generated additional genetic gains for forest plantations by selecting more superior genotypes from the BP (compared to PAM with equal family sizes) for production of improved regeneration materials. These conclusions were verified for a range of heritability under a polygenic model and under a mixed-inheritance model with a QTL contributing to the trait variation