Sheep feeding preference as a tool to control pine invasion in Patagonia: influence of foliar toughness, terpenoids and resin content

ZAMORA-NASCA, LUCÍA B.; DIMARCO, ROMINA D.; NASSINI, DANIELA; ALVEAR, PABLO A.; MAYORAL, ARIEL; NUÑEZ, MARTIN A.; RELVA, M. ANDREA

Scientific Reports

natureresearch

Año: 2020 vol. 10 p. 12113 - 12113

Herbivores modulate the structure and composition of plant communities, including plant invasions.This is conditioned by plant palatability which can be reduced by its chemical or physical traits.Theefects that ungulates browsing has on pine invasions are variable and the empirical evidence on thecauses of this variability is scarce.We experimentally explored how sheep browsing preference variesbetween seedlings of pine species with diferent invasiveness; Pinus contorta (high invasiveness), P.ponderosa (medium invasiveness), P. radiata (medium invasiveness) and P. jefreyi (low invasiveness).Secondly, we quantifed anti-herbivory chemical compounds and physical traits of these species andrelated them with sheep preference observed.The browsing incidence of P. contorta was 68%, P.ponderosa 58%, P. radiata 29%, and P. jefreyi 84%.Among anti-herbivory traits analyzed, α-pineneconcentration had a negative efect on the probability of a terminal bud being browsed and onbrowsing intensity. Meanwhile, foliar toughness was negatively related to browsing intensity andwater concentration was positively related to browsing intensity.Also, the most invasive species, P.contorta, was highly damaged.Thus, sheep herbivory could be slowing pine invasion rate; suggestingthat could be considered a tool to control early invasions, especially for this particular species.