How enriched diet of the second trophic level (Tyrophagus putrescentiae) affects the performance of the third trophic level (Neoseiulus cucumeris): the role of pollens and legumes.

The generalist predatory mite, Neoseiulus cucumeris (Oudemans) (Acari: Phytoseiidae) is one of the most effective biocontrol agents to control the pests of many crops in indoor cultivations. In this study, the effects of the enriched diets of the second trophic level, i.e. the stored-product mite, Tyrophagus putrescentiae (Schrank) on the performance of N. cucumeris as the third trophic level was determined in a tritrophic system. In the first step, different pollens including almond, maize, date palm, castor bean, saffron, and cattail or different legume flours including pinto bean, lentil, black-eyed pea, chickpea, mung bean and broad bean as enrichment additives were added to the basic diet, i.e. a mixture of wheat bran and flour as a basic diet of T. putrescentiae. In the second step, to reveal the effects of the mentioned additives on the performance of N. cucumeris, the demographic parameters of the predator were determined when it was fed with the prey enriched with the additives. Our results indicated that N. cucumeris had higher performance by feeding on the prey reared on diets enriched by either pollens or legumes compared with the basic diet. Overall, there was no significant difference between pollen grains and some legume flours when the predatory mite was fed with them through its prey. Since legumes are more available and cost-effective food sources than pollens, they can be affordable supplementary diets for the mass rearing of N. cucumeris.