title: Desiccation tolerance in diapausing spider mites Tetranychus urticae and T. kanzawai (Acari: Tetranychidae).
abstract: We investigated the effects of changes in vapor pressure deficit (VPD) on the survival of diapausing (winter form) and non-diapausing (summer form) spider mites Tetranychus urticae Koch and Tetranychus kanzawai Kishida (Acari: Tetranychidae). Adult females of both species were kept without food at VPDs of 0.0, 0.4, 0.7, 1.5, 1.9, or 2.7 kPa for 3, 6, 9, 12, or 15 days at 25 °C. Diapausing females of both species kept at a VPD of ≥0.4 kPa for ≥6 days clearly tolerated desiccation. Under water-saturated conditions (VPD = 0.0 kPa), in which no desiccation occurred, diapausing females showed high starvation tolerance: 90 % survived for up to 15 days. No interspecific differences in tolerance to desiccation or starvation were observed under most conditions. These results indicate that diapause functions increase tolerance to desiccation and starvation. Such multiple tolerances to harsh environments might support winter survival in spider mites.
authors.affiliation: Laboratory of Ecological Information, Graduate School of Agriculture, Kyoto University, Kyoto, Kyoto, 606-8502, Japan, noureldinghazy@gmail.com.
authors.forename: Noureldin Abuelfadl
authors.initials: NA
authors.lastname: Ghazy
authors.forename: Takeshi
authors.initials: T
authors.lastname: Suzuki
mesh_terms: D000818:Animals; D003890:Desiccation; D005260:Female; D011157:Population Dynamics; D040102:Tetranychidae / Q000502:physiology*; D014867:Water / Q000378:metabolism
chemical_list: D014867:Water