UNIDAD ASOCIADA "SISTEMAS AGROFORESTALES": ESTACIÓN FITOPATOLÓXICA DO AREEIRO - MISIÓN BIOLÓGICA DE GALICIA
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||First Report of
Bacterial Canker of Kiwifruit Caused by Pseudomonas syringae pv.
actinidiae in Spain
Plant Disease DOI: 10.1094/PDIS-06-11-0537
Publication Acepted 31-08-2011
Mrs. Adela Abelleira Argibay¹, Dr. María Milagros López², Mr. Javier Peñalver Navarro², Dr. Olga Aguín Casal¹, Dr. José Pedro Mansilla Vázquez¹, Mrs. Ana Picoaga Montoussé¹ y Mrs. María José García Fernández¹
¹ Deputación Pontevedra, Estación Fitopatolóxica do Areeiro, Subida a la Robleda s/n, Pontevedra, Spain, 36153
² IVIA, CPVYB, Valencia, Spain, 46113
ABSTRACT: Bacterial canker of kiwifruit caused by Pseudomonas syringae pv. actinidiae was first described in Japan and Korea, and is currently an emerging disease which causes major losses in China, Italy, New Zealand, France, Portugal and Chile. Actinidia chinensis especially cvs. Jin Tao and Hort 16A seem to be more susceptible than green kiwifruit (Actinidia deliciosa) cvs. Hayward and Summer. The bacterium affects both male and female woody vines, with young vines being more susceptible. The most characteristic symptoms that appear in early spring are reddish-orange or white colored exudates associated with cankers and wounds in branches and/or trunk, as well as brown leaf spots, buds and fruits are also affected. Most Spanish kiwifruit is cultivated in Galicia (NW Spain), where the main cultivar is Hayward. In 2010 the first plantation of cv. Jin Tao and one plantation of cv. Summer were established in this area close to Hayward woody vine. In early spring 2011, 80% of the vines of both species showed symptoms of the disease The bacterium, P. syringae pv. actinidiae, was reisolated from symptomatic plants and biochemical tests and molecular tests were performed. Pathogenicity tests were also performed by inoculating healthy vines with the bacterium in which symptoms began to appear five days later whereas uninoculated control vines remained healthy. The kiwifruit orchard with affected plants was eradicated (25 ha). To our knowledge, this is the first report ofP. syringae pv. actinidiae in Spain.
||Primera cita en
España de Psyllaephagus bliteus Riek (Hymenoptera, Encyrtidae),
parasitoide de Glycaspis brimblecombei Moore (Hemiptera, Psyllidae)
BOLETÍN DE SANIDAD VEGETAL
Volume 37 Nº1 2011 Page:37-44
R. Pérez-Otero¹, P. Borrajo², J.P. Mansilla¹, F. Ruiz²
¹ Estación Fitopatolóxica do Areeiro. Subida a la Robleda s/n. 36153 Pontevedra.
² Centro de Investigación Forestal de ENCE. Crtra. A-5000 km 7,5. 21007 Huelva.
RESUMEN: This work is
the first report on the occurrence in Spain of Psyllaephagus bliteus
Riek (Hymenoptera, Encyrtidae) an specific parasitoid of Glycaspis
brimblecombei Moore (Homoptera, Psyllidae) in the province of Huelva (SW
Spain). The parasitoid is native from Australia and is being used as biological
control agent of the suck psillid in many countries.
|First Report of
Cankers and Dieback Caused by Neofusicoccum mediterraneum and
Diplodia corticola on Grapevine in Spain
Plant Disease October 2011, Volume 95, Nº10, Page: 1315
C. Pintos Varela, V. Redondo Fernández, O. Aguín Casal y J. P. Mansilla Vázquez
Estación Fitopatolóxica Do Areeiro, Deputación Pontevedra, Subida a la Robleda s/n. 36153 Pontevedra, Spain
ABSTRACT: In November
2010, four grapevine plants of cv. Crimson from a vineyard located in Sevilla
(south Spain) revealed trunk cankers. Several pathogens were isolated,
including Cylindrocarpon liriodendri (2), Phaeoacremonium
aleophilum (2), Pleurostomophora richardsiae, Neofusicoccum parvum,
and Botryosphaeria dothidea (2). Among Botryosphaeriaceae fungi
isolated on potato dextrose agar (PDA) were two types that did not fit the
above mentioned species. Isolates of type 1 produced an abundant, gray mycelium
with a diurnal zonation that gradually became dark olivaceous. Mycelium growth
occurred from 5 to 37°C with an optimum at 28°C. Conidia were hyaline,
fusiform, aseptate, thin walled, but gradually became obscured and septate with
age, and measured (18.4-) 21.4 (-24.3) × (4.2-) 5.5 (-7.2) µm with
a length/width (L/W) ratio of 4.0 ± 0.5 (n = 100). Isolates of type 1
were identified as N. mediterraneum (3). Single-spore cultures of type 2
developed a whitish, dense, aerial mycelium and remained white up to 10 days on
PDA and darkened to gray thereafter. Mycelium growth occurred from 3 to
37°C with an optimum at 29 to 30°C. Conidia were hyaline, aseptate,
thick walled, oblong to cylindrical, sometimes becoming light brown and one or
two septate after discharge, and measured (24.6-) 30.2 (-42.8) × (10.9-)
14.3 (-18.6) µm with a L/W ratio of 2.1 ± 0.2 (n =100). Isolates
of type 2 were identified as Diplodia corticola (1). Nucleotide
sequences of the ribosomal internal transcribed spacer (ITS) region and the
ß-tubulin genes were used to confirm the identifications through BLAST
searches in GenBank. Comparison of the sequences of types 1 and 2 showed 99 to
100% homology with N. mediterraneum (HM443604 (4) and GU251836) and
D. corticola (AY268421 (1) and EU673117), respectively. Representative
sequences of N. mediterraneum (JF949757 and JF949756) and D.
corticola (JF949758 and JF949759) were deposited in GenBank. The
pathogenicity of one representative isolate of each of N. mediterraneum
and D. corticola was confirmed by inoculating 10 detached grapevine
canes (averaging 12 mm in diameter and 30 cm long) per isolate. A shallow wound
was made with a scalpel on the internodes. A colonized 6-mm agar plug, from the
margin of an actively growing colony, was inserted in every wound and sealed
with Parafilm. Ten grapevine canes controls received only sterile PDA agar
plugs. Canes were maintained at 25°C and 70% humidity. After 5 weeks, all
inoculated canes developed cankers and pycnidia around the inoculation site.
Vascular necroses that developed on the inoculated canes were an average of
28.6 mm for N. mediterraneum and 27.7 mm for D. corticola.
One-way analysis of variance and Tukey's test confirmed significant differences
in the extent of vascular necroses. The average necroses length in the
inoculated canes was significantly greater (P < 0.05) than the average
length of discoloration induced by the simulated inoculation process in the
control. Both pathogens were reisolated from all inoculated plants but not from
controls. To our knowledge, this is the first report of N. mediterraneum
and D. corticola as pathogens on grapevine in Spain.
|Survival time analysis
of Pinus pinaster inoculated with Armillaria ostoyae: genetic
variation and relevance of seed and root traits
European Journal of Plant Pathology Volume 130, Nº4, Page: 477-488
Alejandro Solla1; Olga Aguín2; Elena Cubera1; Luís Sampedro3; J. Pedro Mansilla2; Rafael Zas4
1Ingeniería Técnica Forestal. Universidad de Extremadura, Avenida Virgen del Puerto 2, 10600-Plasencia, Spain
2Estación Fitopatolóxica do Areeiro, Deputación de Pontevedra Unidad Asociada MBGCSIC, Subida a la Robleda s/n, 36153-Pontevedra, Spain.
3Centro de Investigación Forestal de Lourizán Unidad Asociada MBG-CSIC, Apdo. 127, 36080-Pontevedra, Spain.
4Misión Biológica de Galicia, CSIC, Calle Carballeira 8, 36143-Pontevedra, Spain
ABSTRACT: Results of a
greenhouse Armillaria ostoyae inoculation experiment, designed for
screening resistant Pinus pinaster genotypes and for exploring the role
of different phenotypic traits in seedling susceptibility, are reported. The
experiment included 39 open-pollinated pine families that comprised a random
subset of the breeding population of P. pinaster in Galicia (NW Spain).
We employed a non-parametric survival-time analysis to analyze patterns of
survival times during 14 months after inoculation with a local A.
ostoyae strain. Results indicate (i) a significant correlation between seed
weight and tree susceptibility, with seedlings originating from large seeds
being more susceptible, (ii) a positive family mean correlation between
secondary root weight and size and median life expectancy, and (iii) genetic
variation of tree tolerance to A. ostoyae, with some families surviving
significantly longer than others. Less susceptible families could be used in
breeding programmes or directly in forest plantations to reduce the losses
caused by A. ostoyae. Large within-family variation in tolerance to the
disease was also observed, suggesting that non additive genetic variance was
also important. Although being infected, 32 out of the 1200 inoculated trees
survived the fungus infection. These tolerant genotypes comprise an attractive
collection to further investigate genetic, phenotypic and environmental factors
affecting pine susceptibility to Armillaria root
Bursaphelenchus Xylophilus, Causal Agent of Pine Wilt Disease on
Pinus pinaster in Northwestern Spain
Plant Disease June 2011, Volume 95, Nº6, Page: 776
A. Abelleira, A. Picoaga, J. P. Mansilla y O. Aguin
Estación Fitopatolóxica do Areeiro, Subida a la Robleda s/n, 36153 Pontevedra. firstname.lastname@example.org
ABSTRACT: The present work reports the first detection of the pine wood nematode Bursaphelenchus xylophilus in Northwestern Spain; a quarantine organism which is causing serious damage to pines worldwide. In Europe, it was first detected in Portugal in 1999 and in Spain in 2008. Since then, several measures were carried out by the European countries to control the pathogen. 1999, 5,155 samples were analyzed both morphologically and molecularly to monitor the presence of the pathogen in the northern part of Spain. B. xylophilus was detected from a decayed mass of P. pinaster from the As Neves Municipality (Pontevedra, Galicia) in 2010. This area is one of the most productive and important region of Spain for forestry.
|First Report of
Dieback on Hybrid Rhododendrons Caused by Neofusicoccum luteum and N.
parvum in Spain
Plant Disease February 2011, Volume 95, Nº2, Page: 221
C. Pintos Varela, V. Redondo Fernández, J.P. Mansilla Vázquez y O. Aguín Casal
Estación Fitopatolóxica do Areeiro, Subida a la Robleda s/n, 36153 Pontevedra. email@example.com
ABSTRACT: During the conducting of Phytophthora ramorum surveys at Galician public parks (northwestern Spain) in 2010, established Rhododendron spp. plants were observed to be exhibiting leaf spots and necrosis, shoot blight, and cankers and dieback of shoots and branches. N. luteum and N. parvum were identified from these samples first using morphological techniques and then the diagnosis was confirmed by DNA sequences analysis. Pathogenicity of each isolate of N. luteum and N. parvum was confirmed by inoculating four 3-year-old Rhododendron spp. seedlings grown in pots. N. luteum and N. parvum were reisolated from all inoculated plants but not from the controls. To our knowledge, this is the first report of N. luteum and N. parvum on Rhododendron spp. in Spain.