Effects of high temperature and soil moisture on survival of first-instar larvae of the scarab Anoplognathus porosus (Dalman) (Coleoptera).

Published online
01 Jan 1976
Content type
Journal article
Journal title
Journal of Applied Ecology

Hassan, S. T.

Publication language


A laboratory experiment testing survival of first instar larvae of Anoplognathus porosus (Dalm.) at high temperatures and various soil moistures is described. High-temperature stress appears to begin above 32.5 deg C. The mean survival rates for different durations of exposure suggest a gradually increasing level mortality above 30 deg C. The upper lethal temperature is considered to be 40 deg C. In the soil moisture experiments, the very dry soil (2.3% soil moisture, pF 5.6) resulted in total larval mortality after three days. The relatively low soil humidity (75%) caused desiccation. The highest survival was obtained at 4.9% soil moisture (pF 4.2); the concomitant high soil humidity (99%) preventing desiccation. In the very wet soil (40% moisture content, with a layer of water on top of the soil) mortality was high.

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