Susceptibility of Douglas fir ( Pseudotsuga menziesii ) to pitch canker , caused by Gibberella circinata ( anamorph = Fusarium circinatum )
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چکیده
For better characterization of the risk of pitch canker (caused by Gibberella circinata , anamorph = Fusarium circinatum ) to Douglas fir ( Pseudotsuga menziesii ), Californian isolates, selected exotic isolates, and ascospore progeny of a cross between wild-type Californian isolates were tested for aggressiveness to this host species. In addition, seedlings from representative provenances of P. menziesii in California were tested for susceptibility to pitch canker. The results revealed only minor differences between isolates, but differences in susceptibility between trees were often significant. The majority of the tested trees were relatively resistant as indicated by the development of only very short lesions, but some were clearly susceptible.
منابع مشابه
Limiting Effects of Low Temperature on Growth and Spore Germination in Gibberella circinata, the Cause of Pitch Canker in Pine Species
Pitch canker, caused by the fungus Gibberella circinata (anamorph = Fusarium circinatum), was first identified in 1945 as a disease of pines in North Carolina (7). Pitch canker now occurs throughout the southeastern United States where it remains a chronic problem in plantations, nurseries, and seed orchards (2,3). In California, a pitch canker infestation that was first recognized in 1986 has ...
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Pitch canker, caused by Gibberella circinata Nirenberg & O’Donnell, is a problem for pines in both native and planted stands. The aerial phase of the disease results in shoot and canopy dieback, whereas soil or seedborne inoculum can cause damping off of emerging seedlings. Based on the extent of lesion development on inoculated shoots, families of Pinus radiata have been shown to differ signif...
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Pitch canker of pines (Pinus spp.) and Douglas-fir (Pseudotsuga menziesii (Mirbel) Franco) (Pinaceae) is caused by the fungus Fusarium circinatum Nirenberg et O’Donnell. In California, infections by F. circinatum occur largely through wounds caused by insects. Field experiments were initiated to determine whether the colonization activities of twig beetles, Pityophthorus spp. (Coleoptera: Scoly...
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Pitch canker, caused by Fusarium circinatum, is a destructive disease of Pinus species and has recently been shown to represent a substantial threat to natural and commercial forests in northern Spain. The genetic diversity of F. circinatum in the Basque Country of Spain was assessed by characterising 96 isolates based on vegetative compatibility groups (VCGs), mating type assays, polymorphic D...
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