英語(yǔ)翻譯
Sampling methods
Samplings were performed usually every two weeks from April to October 1997.Ten leaves per 2 replicates were collected in each sampling on natural,pure and mixed hedgerows.The leaves were transported to the laboratory where densities of Phytoseiidae and of the most common mite families (e.g.,Tetranychidae,Tenuipalpidae,Eriophyidae,Tydeidae,Winterschmidtiidae) were evaluated under a binocular microscope.Tomonitor vagrant eriophyoids (Eriophyoidea),five different areas of the leaf blade,measuring approximately 1 cm2 each,were explored (25×).Mite species were identified using a phase-contrast microscope.The mean leaf surface of the different plant species ranged from 17.8 cm2 (field maple) to 40.3 cm2 (hazel).Mite densities (except eriophyoids) were expressed as the number of motile forms per 17.8 cm2of leaf surface.