Biology, life table and host specificity of the mushroom pest, Brennandania lambi (Acari: Pygmephoroidea).

Abstract

Biology and life table parameters of Brennandania lambi (Krczal) were studied at different temperatures while feeding on white mushroom (Agaricus bisporus) mycelium cultured on mushroom compost. The duration of egg and larva development, preoviposition and oviposition period, female longevity, and the time to 50% mortality declined as temperature increased from 16 to 28 degrees C. The threshold temperature of development (female) was 9 degrees C and the thermal constant for completion of development (female) was 195 day-degrees. At 16, 20. 24 and 28 degrees C, the total fecundity (eggs/female) was 71, 67, 66 and 57, respectively and the daily fecundity rate (eggs/female/day) was 5.6, 8.7, 8.7 and 9.1, respectively. The sex ratio (female/male) ranged from 1.9 to 2.1 at 16-28 degrees C. At 16, 20, 24 and 28 degrees C, the intrinsic rate of natural increase (rm) was 0.11, 0.18, 0.22 and 0.27, respectively, and the population doubling time was 6.1. 3.9. 3.2 and 2.5 days, respectively. All life stages of the mite died when exposed to 35 degrees C constant temperature for 24h. or to 32 degrees C constant temperature for 12 days or to 31-35 degrees C (average 32.9 degrees C) ambient temperature for 4 days. Brennandania lambi completed development only when fed on Ag. bisporus mycelium growing on mushroom compost. It could not survive on mushroom mycelia of Auricularia auricula. Au. polytricha, Ganoderma lucidum, Hericium erinaceus, Lentinus edodes, Pleurotus ostreatus, P. sajor-caju and Tremella juciformis.