Prey-predator interactions in self-balanced laboratory populations

Abstract

The establishment of a self-perpetuating animal association in an environment that is abiotically uniform appears to be essential for ascertaining and understanding the principles of biotic regulation of populations. If this association so established is of a simple type, such as that of a plant-feeding insect under regulation by one of its natural enemies, the isolation of basic regulatory factors and a study of the operation of each, free of the extraneous or secondary factors which confuse relationships under natural conditions, is possible.Organisms that are eminently suitable for this purpose because they perform as well in the laboratory as in nature are the flour moth, Anagasta kühniella (Zeil.); the predatory mite, Blattisocius tarsalis (Berlese) and the parasitic wasp, Exidechthis canescens (Grav.).Populations of these animals, when placed together, are selfperpetuating and self-regulating and form a permanent ecosystem if periodically provided with adequate amounts of nonviable plant material, such as processed grains of wheat. The ecosystem then consists of one or two "food chains/' the wheat being fed upon by the caterpillar and the caterpillar being fed upon by the parasite; the caterpillar that escapes parasitic attack becomes a moth whose eggs are fed upon by the predatory mite.In the Anagasta ecosystem, the population of each organism attains a numerical balance with its numbers fluctuating around an average density. This average density, however, varies not only with the kind of organism but with the type of regulatory mech anism which may be either the amount of food (food depletion), predatism or parasitism. These mechanisms and the sequence in which they operate can be manipulated by modifying the abiotic environmental factors that determine the extent and frequency of contact between prey and natural enemy. Consequently, the inter action of such populations may be rendered either numerically regulative or numerically nonregulative. The operation of one mechanism may either preclude or supplement the operation of another.continued Inside back cover

Potential of Ascidae, Blattisociidae and Melicharidae (Acari: Mesostigmata) as Biological Control Agents of Pest Organisms

“…Predation by B. tarsalis was also reported on Tineola biselliella (Hummel) and Ephestia sericarium (Scott) (Nesbitt 1951 ). In addition, the mite has been shown to develop and reproduce adequately on A. kuehniella , E. cautella and P. interpunctella (Flanders and Badgley 1963 ;Darst and King 1969 ;Haines 1981 ;Hafez et al 1988 ;Nielsen 1999aNielsen , b , 2001Nielsen , 2003Riudavets et al 2002b ;Çobanoglu et al 2007 ). Flanders and Badgley ( 1963 ), Nielsen ( 1999aNielsen ( , b , 2001Nielsen ( , 2003 B Çobanoglu et al ( 2007 ) Blattisocius tarsalis has also been mentioned to feed on several coleopteran species.…”

“…In addition, the mite has been shown to develop and reproduce adequately on A. kuehniella , E. cautella and P. interpunctella (Flanders and Badgley 1963 ;Darst and King 1969 ;Haines 1981 ;Hafez et al 1988 ;Nielsen 1999aNielsen , b , 2001Nielsen , 2003Riudavets et al 2002b ;Çobanoglu et al 2007 ). Flanders and Badgley ( 1963 ), Nielsen ( 1999aNielsen ( , b , 2001Nielsen ( , 2003 B Çobanoglu et al ( 2007 ) Blattisocius tarsalis has also been mentioned to feed on several coleopteran species. Hase ( 1933 ) reported it (as Blattisocius tineivorus Oudemans) to prey on eggs of Anthrenus verbasci (L.), Anthrenus scrophulariae L. and Anthrenus museorum (L.), while Nesbitt ( 1951 ) reported it to prey on Attagenus piceus Olivier, Tribolium castaneum (Herbst) and Tribolium confusum (J. du Val).…”

“…It seems to feed mainly on insects, having been reported in association with the lepidopterans Sitotroga cerealella Oliver (Oudemans 1929 ), A. kuehniella (Flanders and Badgley 1963 ;Çobanoglu et al 2007 ), Plodia interpunctella (Hübner) (Darst and King 1969 ;Riudavets et al 2002a ) and Ephestia ( Cadra ) cautella (Walker) (Graham 1970 ). Actual predation by B. tarsalis was observed on A. kuehniella by Burkhardt ( 1920 ) and Hase ( 1928 ), who misidentifi ed the mite as Sejus muricatus Oudemans, according to Hase ( 1933 ) (who mentioned it as Typhlodromus tineivorus Koch) as well as by Flanders and Badgley ( 1963 ), Treat ( 1975 ) and Riudavets et al ( 2002a ). Predation by B. tarsalis was also reported on Tineola biselliella (Hummel) and Ephestia sericarium (Scott) (Nesbitt 1951 ).…”

“…Phoresy is usually necessary for mite species specialized on living in patchy habitats that become periodically inadequate for their survival. In a detailed study about predator-prey relation, Flanders and Badgley ( 1963 ) related the ability of Blattisocius tarsalis Berlese to control Anagasta kuehniella (Zeller) in a controlled laboratory study to its phoretic behavior on the latter.…”

Dispersão de Acarophenax lacunatus (Cross & Krantz) (Prostigmata: Acarophenacidae) em trigo armazenado, sob condições artificiais

“…Isso reforça a hipótese de períodos mais longos Profundidade (cm) Número de ovos não-parasitados 10 dias (y = 5,218x;F = 6,72;P < 0,05;Gl = 18;r = 0,27) (Williams & Floyd 1971, Press & Mullen 1992, Flinn et al 1996, Sanon et al 1998, mas para ácaros tais informações são escassas. Flanders & Badgley (1963) comentam que o ácaro B. tarsalis apenas consegue regular a população de Ephestia kuehniella Zeller (Lepidoptera: Pyralidae), em situações onde a profundidade do material não ultrapassa 8 cm. Nielsen (1998), avaliando a capacidade de predação de B. tarsalis, observou que esse ácaro apresenta dificuldades em localizar ovos de E. kuehniella sob uma camada de 1 mm ou mais de farinha.…”