Exploitation of Heterosis: Uniformity and Stability

Janick, J.

doi:10.2134/1999.geneticsandexploitation.c30

Cited by 17 publications

(13 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…More important is the relationship between yielding and competitive ability. These two agronomic traits are distinct and associated in an inverse function (Kyriakou and Fasoulas, 1985;Fasoula, 1990;Sedgley, 1991;Fasoula and Fasoula, 1997;Janick, 1999;Pan et al, 2003;Fasoula and Tokatlidis, 2012;Ninou et al, 2014). This relationship renders nil competition indispensable for avoiding selection of strong competitors at the expense of high yielders.…”

Section: Potential Response To Intracultivar Selectionmentioning

confidence: 99%

Conservation Breeding of Elite Cultivars

Tokatlidis

2015

Crop Science

View full text Add to dashboard Cite

It is now well known that the genome is more flexible and plastic than previously assumed and undergoes constant remodeling and restructuring. Residual heterozygosity and molecular mechanisms that generate de novo variation may result in considerable intracultivar variation. In the long term, cultivars adopted and widely grown by farmers may lose their identity and healthiness. Nevertheless, longevity of elite cultivars is of paramount importance due to time‐consuming and costly endeavors to breed them. Therefore, an appropriate continuous intracultivar selection might be necessary to treat the breeder seed in a sustainable manner. An ultra‐spaced nursery to exclude plant‐to‐plant interference for resources (nil competition) constitutes ideal conditions for two reasons. Nil competition boosts the phenotypic expression of genetic differences so as to make selection applicable within a narrow gene pool. It also erases the masking effects in recognition of the desirable genotypes induced by the negative relationship between yielding and competitive ability. Relevant investigations into several crops have encouraged intense selection at nil competition as a useful technique either to upgrade or to avoid gradual degradation of the genetic background to maintain uniformity and secure optimal quality of breeder seed over longer periods of time. A conservation breeding strategy is presented, comprising a periodical selection round to secure breeder seed devoid of harmful alterations and consecutive selection rounds to produce prebasic seed of high quality. Beyond uniformity and sanitary status, conservation breeding will help to enhance cultivar longevity through adaptation to a continuously changing environment.

show abstract

Section: Potential Response To Intracultivar Selectionmentioning

confidence: 99%

Conservation Breeding of Elite Cultivars

Tokatlidis

2015

Crop Science

View full text Add to dashboard Cite

show abstract

“…The link between phenotypic plasticity and heterosis has been well documented for annual plants, notably maize (Janick 1999; Gallais 2009). Usually, hybrids are able to stay productive in environments where one or both parents’ performances drop.…”

mentioning

confidence: 99%

Deciphering Hybrid Larch Reaction Norms Using Random Regression

Marchal

Schlichting

Gobin

et al. 2019

G3 Genes|Genomes|Genetics

View full text Add to dashboard Cite

The link between phenotypic plasticity and heterosis is a broad fundamental question, with stakes in breeding. We report a case-study evaluating temporal series of wood ring traits of hybrid larch (Larix decidua × L. kaempferi and reciprocal) in relation to soil water availability. Growth rings record the tree plastic responses to past environmental conditions, and we used random regressions to estimate the reaction norms of ring width and wood density with respect to water availability. We investigated the role of phenotypic plasticity on the construction of hybrid larch heterosis and on the expression of its quantitative genetic parameters. The data came from an intra-/interspecific diallel mating design between both parental species. Progenies were grown in two environmentally contrasted sites, in France. Ring width plasticity with respect to water availability was confirmed, as all three taxa produced narrower rings under the lowest water availability. Hybrid larch appeared to be the most plastic taxon as its superiority over its parental species increased with increasing water availability. Despite the low heritabilities of the investigated traits, we found that the expression of a reliable negative correlation between them was conditional to the water availability environment. Finally, by means of a complementary simulation, we demonstrated that random regression can be applied to model the reaction norms of non-repeated records of phenotypic plasticity bound by a family structure. Random regression is a powerful tool for the modeling of reaction norms in various contexts, especially perennial species.

show abstract

“…Heterosis in plants is a phenomenon that usually arises in unfavorable environments, as observed in a wide range of crop hybrids, like corn (Janick 1999; Gallais 2009). The relative stability of hybrids when the parents’ performances drop is called ‘hybrid homeostasis’ and, as a consequence, the hybrids are often expected to perform better than their parents in most environmental conditions.…”

Section: Introductionmentioning

confidence: 99%

Deciphering hybrid larch reaction norms using random regression

Marchal

Schlichting

Gobin

et al. 2018

Preprint

View full text Add to dashboard Cite

The link between phenotypic plasticity and heterosis is a broad fundamental question, with stakes in breeding. We report a case-study evaluating temporal series of wood ring traits of hybrid larch (Larix decidua × L. kaempferi and reciprocal) in relation to soil water availability. Growth rings record the tree plastic responses to past environmental conditions, and we used random regressions to estimate the reaction norms of ring width and wood density with respect to water availability. We investigated the role of phenotypic plasticity on the construction of hybrid larch heterosis and on the expression of its quantitative genetic parameters. The data came from an intra-/interspecific diallel mating design between both parental species. Progenies were grown in two environmentally contrasted sites, in France. Ring width plasticity with respect to water availability was confirmed, as all three taxa produced narrower rings under the lowest water availability. Hybrid larch appeared to be the most plastic taxon as its superiority over its parental species increased with increasing water availability. Despite the low heritabilities of the investigated traits, we found that the quantitative genetic parameters varied along the water availability gradient. Finally, by means of a complementary simulation, we demonstrated that random regression can be applied to model the reaction norms of non-repeated records of phenotypic plasticity bound by a family structure. Random regression is a powerful tool for the modeling of reaction norms in various contexts, especially perennial species.

show abstract

Exploitation of Heterosis: Uniformity and Stability

Cited by 17 publications

References 8 publications

Conservation Breeding of Elite Cultivars

Conservation Breeding of Elite Cultivars

Deciphering Hybrid Larch Reaction Norms Using Random Regression

Deciphering hybrid larch reaction norms using random regression

Contact Info

Product

Resources

About