GROWTH OF HARTWEG'S PINE (PINUS HARTWEGII) PARASITIZED BY TWO DWARF MISTLETOE SPECIES (ARCEUTHOBIUM SPP.)
Por:
Queijeiro-Bolanos, Monica E., Cano-Santana, Zenon
Publicada:
1 ene 2016
Categoría:
Plant Science
Resumen:
Coniferous forests occupy a large extent (17 %) of the Mexican
territory. Within these forests, pines are a common and sometimes
dominant component; however, several abiotic and biotic factors affect
pines growth. Among the main biotic factors is the parasitic effect of
dwarf mistletoes. In Zoquiapan (Iztaccihuatl Popocatepetl National Park,
Central Mexico) two dwarf mistletoe species coexist parasitizing Pinus
hartwegii. The aim of this study was to know the effect of Arceuthobium
globosum and A. vaginatum, either individually or as a pair, on P.
hartwegii growth, allometric relations, and size susceptibility. We
recorded diameter at breast height (dbh) and crown spread of P.
hartwegii for 3 years on individuals infested by either one of the
species, both, or none, as well as the infection severity. The relative
growth rate (RGR) in diameter was strongly influenced by the pines
initial dbh; whereas the infecting species or severity did not show a
differential effect. The allometric relation of dbh and height was
affected by parasitism, where the trees infected by both species were
shorter than the uninfected and infected by A. vaginatum at the same
dbh. The parasitic effect does not differ among these mistletoe
species., However, the host-size structure affects the presence and
severity of infection; maintaining even-age stands provides a better
scenario for a milder effect of parasitism, which should be considered
for managing plans.
Filiaciones:
Univ Nacl Autonoma Mexico, Dept Ecol & Recursos Nat, Fac Ciencias, Mexico City, DF, Mexico
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