Improved quantitative method for isolating Calonectria ilicicola from naturally infested soils

摘要

We developed an improved procedure for quantitative isolation of Calonectria ilicicola from naturally infested soils. The selective medium contained 20 g l-sorbose, 4 g yeast extract, 12.5 mg flutolanil, 1.5 mg thiabendazole, 40 mg chlortetracycline hydrochloride, 10 mg chloramphenicol, 1 mL tergitol, 20 g agar, and up to 1 L with distilled water. Soil samples are wet-sieved (mesh size 0.250–0.038 mm) and then surface-sterilized for 30 s with 0.25 % NaClO solution before incubation with this medium. Compared with previously reported methods, this method was more effective for isolating C. ilicicola, and the amount of contamination was decreased.