INVESTIGADORES
PASTORINO Mario Juan
artículos
Título:
Heritable variation in the survival of seedlings from Patagonian cypress marginal xeric populations coping with drought and extreme cold.
Autor/es:
APARICIO, ALEJANDRO; ZUKI, SEBASTIÁN; PASTORINO, MARIO JUAN; MARTINEZ MEIER, ALEJANDRO; GALLO, LEONARDO ARIEL
Revista:
TREE GENETICS & GENOMES
Editorial:
SPRINGER HEIDELBERG
Referencias:
Lugar: HEIDELBERG; Año: 2012 vol. 8 p. 801 - 810
ISSN:
1614-2942
Resumen:
The rear edges of tree species have begun to be
perceived as highly valuable for genetic resources conservation
and management. In view of expected climatic
changes, the responses of trees at their xeric limits may
largely be determined by their capacity to cope with augmented
environmental variance.We assess the heritability of
early survival of Patagonian cypress in two common-garden
field tests with contrasting summer water deficits, comprising
140 and 163 open-pollinated families from 10 marginal
xeric populations. The first experiment underwent less rigorous
conditions than the average mesic, Mediterranean
climatic conditions, which were sufficient to reveal additive
genetic effects of summer drought on seedling survival. The
second trial suffered strong summer water-deficit stress and
a winter extreme cold event. In this harsher environment, the
heritabilities of survival under summer water-deficit stress
were high in all the populations (h200.84 on average), while
the heritabilities of seasonal, extreme cold survival were
moderate or even nil (h200.28 on average). We did not find
evidence of genetic differentiation among populations in
their capabilities to survive droughts and cold extremes.
Our results indicate that even when climatic changes were
strong enough to cause the extinction of the most threatened
populations, heritable variation for traits underlying drought
and cold tolerances may allow the marginal xeric edge of
cypress to persist under augmented environmental variance,
without losing overall genetic diversity.