Aureobasidium pullulans, a ubiquitous saprophytic fungus on many fruits and very rarely reported to cause disease on pine needles. No symptoms were observed on control plants. pullulans, was reisolated from those lesions, confirming Koch's postulates. After 10 days, typical symptoms appeared on inoculated needles, whereas control needles remained symptomless. Inoculated and non-inoculated plants were kept in humid chambers in a glasshouse. The suspension was sprayed onto 3 annual seedlings' needles, and the control was sprayed with sterile water. For the pathogenicity test, a conidial suspension was prepared with a concentration of 2.0 × 107 conidia/ml. MW228368 for ITS and MW256762 for β-tubulin) showed high similarity with BLAST sequences of Aureobasidium pullulans (ITS, KR704881 β-tubulin, MT671934 ). The sequences submitted to GenBank (Accession Nos. DNA was extracted from the mycelium of the isolate by the cetyltriethylammonium bromide (CTAB) method and amplified through polymerase chain reaction (PCR) with the internal transcribed spacer (ITS) region of rDNA and partial β-tubulin genes of a representative isolate (SC05) were amplified using the ITS1/ITS4 and Bt2a/Bt2b primer pairs, respectively(Wu et al. Conidia were hyaline, smooth-walled, single-celled, and ellipsoidal with variable shape and size, 7.5 to 16 × 3.5 to 7 µm (Zalar et al. The colonies initially appeared white to cream, yeast-like, and later turned to pink and remained at least 10 days. Pure cultures were obtained by monosporic isolation. Small cut tissues were placed on potato dextrose agar (PDA) at 25℃ for 10 days. To determine the pathogen, 20 needle samples with typical symptoms were disinfected with 75% alcohol, and sections of the tissue were cut from joints of diseased and healthy tissues (visually healthy) with a sterilized scalpel, surface sterilized for 45 seconds in 75% alcohol, soaked for 90 seconds in 1.5% NaCIO, rinsed in sterilized water and dried. The tips of old needles first turn grayish green and developed into brown bands ranging from 1 to 2 mm. Further surveys showed that these symptoms are common while the disease incidence is less than 30% which indicated the severity of the disease is mild. In August 2020, needle blight symptoms were found on several trees of black pine in Sichuan Province, China. The timber of this species can be used for infrastructure construction and furniture production. This pine variety can prevent soil desertification and promote soil conservation and is excellent for constructing fast-growing forests and shelter belts. Pinus thunbergii Parl., known as black pine, is widely distributed all over China.
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