|
|
|
XII Congreso de
la Sociedad Española de Fitopatología (SEF), 2004
|
3959 |
|
Patogenicidad de Armillaria Mellea, Armillaria Ostoyae y
Armillaria Gallica sobre coníferas
Aguín,O¹. Mansilla, J.P¹,².; Sáinz, M.J.
²
1 Estación Fitopatolóxica do Areeiro, Excma.
Diputación Provincial de Pontevedra, Subida a la Robleda s/n, 36153
Pontevedra, España.
2 Departamento de Producción Vegetal.
Universidad de Santiago de Compostela. 27002 Lugo
|
ABSTRACT: In Galicia, white
root rot in conifers is mainly caused by Armillaria ostoyae and in a
lower extent by Armillaria mellea. In this region most of the
symptomatic samples of Pinus spp. submitted for diagnosis were affected
by A. ostoyae, whereas a lower number corresponded to A. mellea.
Armillaria gallica was also reported in conifers, but was considered as
a weak pathogen. An experiment was carried out in growth chamber to study A.
mellea , A. ostoyae and A. gallica pathogenicity in four
forestry conifers in Galicia: P. pinaster, P. sylvestris, P.
radiata and Pseudotsuga menziesii. Plant was produced from seed
taken from each conifer using as a substrate a sterile mix of pine bark, peat
and perlite. After six months, well developed and healthy plants were
transplanted to 500 ml pots with similar substrate. Three months later,
inoculation treatments were established, separately or combining two or three,
and were compared to the control. During the assay and for each plant, symptoms
were monitored, quantifying the size and weight of the aerial, root and
rhizomorph biomass in the substrate, establishing a disease index. Rhizomorph
samples were taken to identify the Armillaria species by means of
molecular techniques. For every conifer disease symptoms (aerial decay, needle
yellowing..) were observed in inoculation treatments with Armillaria
mellea. A. ostoyae, A. mellea and A. gallica reduced
Pinus and Pseudotsuga species growth, but only A. ostoyae
and A. mellea caused damage in the aerial part of the plant. Some
species combinations, such as A. ostoyae with A. gallica in
Pinus radiata together caused more important damage in the plant, than
inoculated separately
|
|