Document Type : Research Paper
Authors
1
Ph. D. Candidate, Department of Plant Protection, University College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran
2
Associate Professor, Department of Plant Protection, University College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran
3
Assistant Professor, Horticultural Science Research Institute, Pistachio Research Center, Agricultural Research, Education and Extension Organization (AREEO), Rafsanjan, Iran
4
Professor, Department of Plant Protection, University College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran
Abstract
Pistachio die-back disease is an important disease in Iranian pistachio orchards. One of the most important fungal agents of the disease is Paecilomyces which has been recently identified as P. formosus based on phylogenetic and physiologic studies. In this study, four pairs of primers designed using mating type idiomorph sequences of P. variotii deposited in GenBank (NCBI). Designed primers were tested in some isolates of P. formosus and finally two primer pairs including; Mat1-1f224 and Mat1-1r224 for amplification of Mat1-1 and Mat1-2f165 and Mat1-2r165 primers for amplification of Mat1-2 idiomorphs were selected. Mating type idiomorphs were amplified in 124 isolates of P. formosus which have been obtained from pistachio trees and eight other species including; Pistacia mutica, Punica granatum, Prunus amygdalus, Caesalpinia gilliesii, Nerium oleander, Tamarix aphylla, Tamarix hispida, Haloxylon sp. and air of pistachio orchards. In 50 isolates (40.3%) Mat1-1, in 59 isolates (47.6%) Mat1-2 and in 15 isolates (12.1%) both idiomorphs were identified. 16 isolates from each mating type and three isolates which had both idiomorphs were selected and crossed in all of the possible combinations on PDA culture medium and cultures were incubated at 25 °C in continuous dark condition. After eight months, sexual reproduction was not observed in crosses.
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