1,720,972 research outputs found
Studio e definizione delle sindromi in Capitanata (Foggia) - Mal dell’esca, un nuovo agente individuato in Puglia
No full textDelineando le sintomatologie più diffuse, correlando
i sintomi esterni sulle foglie a quelli interni sul legno,
si è cercata una diretta associazione tra i sintomi
e le specie fungine isolate dai tessuti sintomatici.
Accanto agli agenti noti è stata rilevata e associata
al complesso del mal dell’esca Pleurostomophora
richardsiae, prima d’ora segnalata solo in Sud Afric
First Report of Stem Wilt and Root Rot of Schlumbergera truncata Caused by Fusarium oxysporum f. sp. Opuntiarum in Southern Italy
No full textSchlumbergera truncata (Haw.) Moran, belonging to the Cactaceae, is a very common ornamental cactus in southern Italy. In November 2011, sudden stem wilt and root rot was observed in about 45% of vegetatively propagated plants cultivated as potted ornamental plants in a commercial greenhouse in Cerignola (Foggia Province, Apulia, Italy). The roots and collars of the plants showed brown rot. Yellow sunken lesions that were similar to cortical cankers were detected at basal level of the stem. Ten plants with these symptoms were analyzed by fungal isolation techniques. Small (0.5 cm) tissue portions from root, collar, and basal stem were plated on potato dextrose agar (PDA) after disinfection with 75% ethanol for 1 to 2 min, 0.2% NaOCl for 1 to 2 min, and a wash with sterile distilled water. A fungal isolate that was morphologically similar to Fusarium sp. was isolated from 85% of these tissue samples. It had nucleotide sequences of the internal transcribed spacer region (ITS1-5.8S-ITS2) of ribosomal DNA (GenBank Accession No. KC196121) 100% identical to those of the comparable sequences of Fusarium oxysporum (HQ651161). The nucleotide sequences of its translation elongation factor 1-α (EF-1α) gene (KC196120) showed 100% identity to sequences of F. oxysporum f. sp. opuntiarum (DQ837689, AF246881) retrieved from GenBank. Pathogenicity tests were performed at 22 ± 3°C on 18 45-day-old plants of S. truncate by adding of a 5-ml aliquot of conidial suspension adjusted to 5 × 106 conidia/ml to soil of each plant. Six non-inoculated plants were used for a control treatment and sprayed with 5 ml of sterilized water. Plants were maintained in greenhouse at 22 ± 3°C. After 10 days, nine of the inoculated plants showed wilting, and after 45 days, all of them were dead, with root and collar rot and lesions on the basal stem. Control plants were symptomless. Koch's postulates were fulfilled as the pathogen was reisolated from all of the symptomatic tissues and identified as Fusarium sp. On the basis of 3-septate macroconidia (mean 31.75 × 3.21 μm; range, 26 to 35 μm long, 3.0 to 4.2 μm wide), aseptate microconidia, single chlamydospores, and monophialide conidiophores on carnation leaf agar, and molecular analyses, the fungus was identified as F. oxysporum f. sp. opuntiarum (Speg) (1,2,3). In Italy, F. oxysporum f. sp. opuntiarum was reported as basal stem rot of Echinocactus grusoni (4). To our knowledge, this is the first report of stem wilt and root rot of S. truncata caused by F. oxysporum f. sp. opuntiarum in Italy
Study and definition of the syndrome of esca complex of grapevine in Capitanata (southern Italy)
No full textCharacterization of Botryosphaeriaceae Species as Causal Agents of Trunk Diseases on Grapevines
No full textBotryosphaeriaceae spp. have a cosmopolitan distribution and a wide range
of plant hosts. Over the last 15 years, worldwide, 21 species of this family
have been associated with grapevine trunk diseases that cause cankers and
dieback on grapevines. Here, we surveyed vineyards of Vitis vinifera ‘Lambrusco’,
‘Sangiovese’, and ‘Montepulciano’ in three areas of the Foggia
province (Cerignola, Foggia, and San Severo) in southern Italy. Wood samples
from grapevines showing general decline, dieback, cankers, and wood
and foliar discoloration yielded 344 fungal isolates identified as Botryosphaeriaceae
spp.Aphylogenetic study combining internal transcribed spacer
and translation elongation factor 1-a sequences of 60 representative isolates
identified nine botryosphaeriaceous species: Botryosphaeria dothidea, Diplodia
corticola, D. mutila, D. seriata,Dothiorella iberica, Do. sarmentorum,
Lasiodiplodia citricola, L. theobromae, and Neofusicoccum parvum. Pathogenicity
tests confirmed that all nine species cause canker and dieback of
grapevines. However, this is the first report of L. citricola as causal agent
of wood cankers and dieback of grapevine. To date, including L. citricola,
there are 25 botryosphaeriaceous species associated with V. vinifera worldwide,
of which 12 have been reported for grapevines in Italy
Study and definition of the syndromes of the esca complex of grapevine in Capitanata (Southern Italy)
No full textoral presentatio
Phaeoacremonium species associated with olive wilt and decline in southern Italy
Full text linkSix Phaeoacremonium species (spp.) were isolated from symptomatic wood of olive
trees (Olea europea) in Apulia (southern Italy) that showed crown wilt and twig and
branch dieback. These Phaeoacremonium spp. were identified according to their
morphological characteristics and analyses of partial sequences of the actin and β-
tubulin genes. Combining these culture, morphological and molecular data, three
Phaeoacremonium spp. were isolated that are already known to be responsible for
severe decline of olive in Apulia, Phaeoacremonium aleophilum, Phaeoacremonium
alvesii and Phaeoacremonium parasiticum, together with three other
Phaeoacremonium spp. that are associated for the first time with wilt, decline and
dieback of olive orchards in Italy and worldwide: Phaeoacremonium italicum,
Phaeoacremonium sicilianum and Phaeoacremonium scolyti. To understand and to
confirm their involvement in wilt and decline of olive trees, pathogenicity assays were
performed on shoots of young olive plants. The data indicate that all six of these
Phaeoacremonium spp. can cause discoloration, necrotic wood, and death of shoots,
although different levels of virulence were observed, with Pm. italicum, Pm. aleophilum
and Pm. sicilianum producing greater necrotic lesions than the other
Phaeoacremonium spp. investigated here
Effetti dell'irrigazione con acque reflue agroindustriali depurate sulle caratteristiche chimiche e miscobiologiche del terreno
No full textProteolytic activity of molds and their metabiotic association with Salmonella in a model system
No full textABSTRACT
The aim of this study was to investigate the proteolytic ability of some strains of aspergilli, fusaria, and penicillia and the metabiotic effect of Fusarium oxysporum and Penicillium expansum on Salmonella. The proteolytic activity of the target molds was determined on tomato juice agar and tomato juice, whereas the metabiotic effect of F. oxysporum and P. expansum on Salmonella was assessed in a model system consisting of tryptone soy broth with different amounts of tomato juice added. Fusaria, some aspergilli, and one strain of penicillium showed a proteolytic activity on tomato juice agar. In addition, Sal- monella survival was enhanced in tryptone soy broth plus 20 or 50% tomato juice in the model system previously inoculated with F. oxysporum
Effects of high-pressure homogenization on the survival of Alicyclobacillus acidoterrestris in a laboratory medium
No full text- …
