Relative Dominance of the Mold Fungus,Raffaeleasp., in the Mycangium and Proventriculus in Relation to Adult Stages of the Oak Platypodid Beetle,Platypus quercivorus(Coleoptera; Platypodidae)

Death of Quercus crispula by inoculation with adult Platypus quercivorus (Coleoptera: Platypodidae)

“…ex Murray) has been reported in several prefectures along the Sea of Japan, in the southern part of Kyushu Island and on the Kii Peninsula since the latter half of the 1980s (Kinuura, 1994;Ito, 2002). Numerous tunnels of the ambrosia beetle Platypus quercivorus (Murayama) were observed in all dead and dying trees, and an unknown species of moniliaceous fungus was isolated predominantly from discolored sapwood, beetle galleries in dead oak trees, and the body surfaces and mycangia of P. quercivorus Kinuura, 2002). Platypus quercivorus, which belongs to the family Platypodidae, bores into stems and constructs a gallery called a pinhole in the sapwood.…”

“…Therefore, the first two requirements have been met. In addition, R. quercivora have been isolated from beetle galleries in dead trees as well as from the proventriculus and mycangia of P. quercivorus (Kinuura, 2002), meeting the third requirement. However, wilting symptoms have not been reproduced by inoculation of P. quercivorus into healthy trees, although Q. crispula that were greatly stressed by debarking were inoculated and death was induced (Kinuura, 2005).…”

Rearing technique for the oak platypodid beetle, Platypus quercivorus (Murayama) (Coleoptera: Platypodidae), on soaked logs of deciduous oak tree, Quercus serrata Thunb. ex Murray

“…In ambrosia beetles, the fungal growth in the gallery system determines the rate of growth of the brood (Kaneko, 1965) and initial oviposition time (Kingsolver and Norris, 1977). Kobayashi et al (2001) reported that the colonization of logs by fungi pathogenic to oak trees, carried by P. quercivorus (Kinuura, 2002), might be related to the successful reproduction of the borer. Therefore, the different progeny development among galleries or logs (Table 3) may be caused by the different growth of fungi associating with P. quercivorus in their galleries or logs.…”

Virulence of Raffaelea quercivora isolates inoculated into Quercus serrata logs and Q. crispula saplings

“…In early summer, a large number of ambrosia beetles (P. quercivorus) attack the trunks of living oak trees and bore numerous galleries into the sapwood. The female beetle has mycangia, which store spores of symbiotic fungi, in the pronotum (Kinuura 2002), and introduces R. quercivora into the galleries. The introduced R. quercivora stops sap flow nearby the galleries, and the tree dies when the ascent of sap is completely blocked at any cross-section of the tree (Kuroda and Yamada 1996;Kuroda 2001;Murata et al 2007Murata et al , 2009.…”