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Semiochemical-based mass trapping of the striped ambrosia beetle, Trypodendron lineatum (Olivier) (Coleoptera: Scolytidae), has been the cornerstone of an integrated pest management (IPM) programme for ambrosia beetles on the British Columbia coast since 1981. However, there is no available tactic of protecting logs from attack that could be incorporated into the IPM programme. We tested nonhost volatiles (NHVs) from the bark of angiosperm trees for their ability to disrupt catches of T. lineatum in multiple-funnel traps baited with the aggregation pheromone lineatin. In one set of experiments, a blend of 1-hexanol and benzyl alcohol caused 77.9% and 80.0% reduction in captures of males and females, respectively, and in another a blend of methyl salicylate and salicylaldehyde caused reductions of 65.0% for males and 66.9% for females. All four NHVs combined caused reductions in captures for males and females of 82.3% and 81.4%, respectively, not much greater than to the blend of 1-hexanol and benzyl alcohol. However, because both blends were active alone, their redundancy when combined lends confidence to the selection of the four-component blend for operational testing. Although disruption was increased when a 16-component NHV blend was tested, or when (±)–(E)-conophthorin was added to the four-component blend, addition of more compounds to the four-component blend was not considered operationally or economically justifiable. When deployed from low-density polyethylene tubes stapled along the length of pheromone-baited conifer logs, this blend caused prolonged and significant reductions in landing by T. lineatum and also by Gnathotrichus sulcatus (LeConte) and G. retusus (LeConte) (Coleoptera: Scolytidae). However, attacking beetles generally overcame the NHV treatment by the end of the flight period, leading to similar attack densities on treated and control logs. Therefore, we recommend that further operational investigations explore using repellent NHVs in combination with disruptive visual, tactile or gustatory stimuli.  相似文献   
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This paper overviews a variety of traditional agroforestry systems found in a small community of Filipino migrant farmers. Background information provides context, and then case studies of seven farmers are offered to illustrate the functions which their agroforestries fulfill in a situation of parcellization of farm-holdings into both level and sloping fields. The implications of the brief portraits presented for further research and development and for the acceptability of a social forestry program now going on in the community are suggested.  相似文献   
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The antibiotic sulfadiazine (SDZ) can affect denitrifying bacteria in soil. However, effects on denitrifiers in the gut of earthworms have not been described so far. Therefore, the influence of SDZ-contaminated manure applied to soil on denitrifiers in the gut of the earthworm Eisenia fetida was assessed by quantitative polymerase chain reaction targeting genes coding for nirK- and nirS-type nitrite reductases of denitrifiers. Gut contents of Eisenia fetida contained 2.5 × 106 and 5.1 × 105 gene copies of nirK and nirS, respectively, after 2 weeks in soils amended with manure only. Copy numbers of nirK and nirS in gut contents from manure treatments with SDZ were up to ten times less. Overall, the data indicate a negative impact of SDZ on denitrifiers in the gut of earthworms.  相似文献   
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