Field and laboratory studies on drought tolerance and water balance in adult Pergalumna nervosa (Acari: Oribatida: Galumnidae)

0474917 - BC 2018 RIV CZ eng J - Journal Article
Slotsbo, S. - Sorensen, J. G. - Starý, Josef - Holmstrup, M.
Field and laboratory studies on drought tolerance and water balance in adult Pergalumna nervosa (Acari: Oribatida: Galumnidae).
European Journal of Entomology. Roč. 114, January (2017), s. 86-91. ISSN 1210-5759. E-ISSN 1802-8829
Institutional research plan: CEZ:AV0Z60660521
Institutional support: RVO:60077344
Keywords : oribatid mites * drought * soil water potential * osmolality * water loss * permeability
OECD category: Biology (theoretical, mathematical, thermal, cryobiology, biological rhythm), Evolutionary biology
Impact factor: 1.017, year: 2017

We studied the water balance, body fluid osmolality and survival of the oribatid mite, Pergalumna nervosa, when exposed to drought in field and laboratory experiments. In a replicated field experiment we artificially lowered the soil water content by putting roofs over selected plots, which reduced soil water potential to levels well below the permanent wilting percentage for plants (i.e. below -1.5 MPa). Even though a slight decrease in the abundance of P. nervosa (only found in the 0-5 cm soil layer) was recorded during the most severe drought stress (ca. -3.5 MPa), the majority of adult mites clearly survived these conditions for 3 weeks in the field without migrating to deeper soil layers. Exposing field collected adults in laboratory experiments simulating even more severe drought conditions revealed that P. nervosa can survive several weeks of gradually increasing drought stress (down to -7 MPa) with moderate water loss. The osmolality of body fluids increased as dehydration progressed, but apparently as a result of simple up-concentration of solutes and not the de novo synthesis of protective osmolytes. We compare and discuss these results in the light of what is known about other arthropods.
Permanent Link: http://hdl.handle.net/11104/0277683