![]() The culprit of the needle discoloration is believed to be the fungal disease known as brown spot needle blight.įrom the Alabama Forestry Commission: Historically, this disease has only infected longleaf pines (Pinus palustris). Many of these calls have been coming from counties in the northwest and northeast regions of the state, according to AFC. Since early spring, the Alabama Forestry Commission (AFC) has received phone calls about pine needles suddenly turning brown. (WBRC) - A fungal disease that’s affecting pine trees has been detected in 36 of 67 counties in Alabama, according to the Alabama Forestry Commission. Systematic Mycology and Microbiology Laboratory, ARS, USDA. Occurrence of the disease in Korea is a new threat to the health of black pine, especially in nursery plots. To our knowledge, this is the first report of the Lecanosticta-Pinus association in Korea. The disease has been previously reported on several species of Pinus in the Americas (1) and recently in China (3), Japan (4), and Europe (2). No symptoms were observed on control plants. acicola, was reisolated from those lesions, confirming Koch's postulates. After 28 days, typical leaf spot symptoms started to develop on the needles of inoculated plants. Inoculated and noninoculated plants were kept in humid chambers for 48 h in a glasshouse. ![]() Five noninoculated seedlings of the same age served as controls. 2 × 10 5 conidia/ml) was prepared by harvesting conidia from 5-week-old cultures of KACC44982 and sprayed onto the needles of five 3-year-old healthy seedlings. To conduct a pathogenicity test, a conidial suspension (approx. Don from France (GU214663), with 100% sequence similarity. mugo Tura from Lithuania (HM367708) and P. A GenBank BLAST search produced an exact match for the sequences of M. The resulting ITS sequence of 543 bp was deposited in GenBank (Accession No. Genomic DNA was extracted using the DNeasy Plant Mini DNA Extraction Kit (Qiagen Inc., Valencia, CA) and the complete internal transcribed spacer (ITS) region of rDNA was amplified and sequenced with the primers ITS1/ITS4. An isolate was preserved at the Korean Agricultural Culture Collection (Accession No. On potato dextrose agar, single-spore cultures of three isolates were obtained from conidia sporulating on needles. Barr), previously known as the causal agent of brown spot needle blight of pines (2,4). (anamorph of Mycosphaerella dearnessii M.E. Morphological characteristics of the fungus were consistent with those of Lecanosticta acicola (Thüm.) Syd. Conidia (n = 30) were olivaceous brown to grayish brown, verrucose, thick-walled, mildly curved, allantoid to fusiform, one- to five-septate (mostly three-septate), and 20 to 45 × 3.5 to 5 μm. Conidiophores were simple or occasionally branched, 1- to 2-septate, pale brown to olivaceous brown, and smooth walled. ![]() Dark olivaceous to dark grayish stromata were erumpent and conspicuous on the brown lesions in the later stage of disease development. The spots developed into brown bands reaching 1 to 2 mm long, sometimes with yellow margins. Small, circular grayish green spots first appeared on the needles. Further surveys in 20 showed that these symptoms are rather common but disease incidence is less than 1%. In March 2010, needle blight symptoms were found on several trees of black pine in Naju, southern Korea. Because of its resistance to pollution and salt, it is planted as windbreakers along the coast. Pinus thunbergii Parl., known as black pine, is a pine native to coastal areas of Japan and Korea. ![]()
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