云杉八齿小蠹蓝变菌的生物学特性和杀菌剂筛选

云杉八齿小蠹伴生蓝变真菌侵害云杉属和松属,严重可导致树木死亡.经室内试验研究,结果表明:2个蓝变菌菌株适宜生长温度均为25℃,对酸碱度的适应能力强,当pH值在3.5~9.0范围内均能生长,在酸性环境下发育较好,以葡萄糖为最佳碳源.此外,菌株Ophiostoma penicillatum可很好利用乳糖,最佳氮源为甘氨酸和酵母粉;菌株Ophiostoma sp.可较好利用甘露糖,最佳氮源为蛋白胨.甲基托布津、扑海因和中生菌素对试验菌株的生长有极强的抑制效果,腐霉利、噻菌铜和霜霉威对Ophiostoma penicillatum有显著的抑制效果,且试验使用的浓度仅为药剂常用浓度的1/10.     

Green leaf volatiles interrupt aggregation pheromone response in bark beetles infesting southern pines

Summary Green leaf volatiles were shown to interrupt responses to aggregation pheromones of three species of bark beetles (Coleoptera: Scolytidae) which infest pines in the southern United States [the southern pine beetle,Dendroctonus frontalis Zimm.; the four-spined engraver,Ips avulsus (Eichhoff); and the five-spined engraver,Ips grandicollis (Eichhoff)]. The order of effectiveness of the compounds tested for each species was hexanal>hexanal+hexan-1-ol>hexan-1-ol. Neither hexanal, hexan-1-ol nor hexanal+hexan-1-ol was as effective in interrupting pheromone responses ofD. frontalis as verbenone, a known inhibitor of this species. Other than interspecific chemical signals, this is the first report of an interruptant forIps species, and the only report of a pheromone interruptant active for bothIps andDendroctonus species.     

On the specific attraction of the males of the six-toothed spruce bark beetle,Pityogenes chalcographus (L.) to a mixture of synthetic pheromones of the eight-toothed spruce bark beetle,Ips typographus (L.) (Coleoptera,Scolytidae)

Summary Traps containing a mixture of attractants forIps typographus also caught other species of bark beetles. The numbers ofPityogenes chalcographus, Pityogenes conjunctus, andTrypodendron lineatum were too high to be interpreted as accidental captures. The males of the polygamousP. chalcographus were specifically attracted, indicating that theI. typographus pheromone or one of its components acts as a kairomone and primary attractant for the pioneering males ofP. chalcographus.