The use of factitious food instead of natural prey, and artificial substrates instead of leaf-based, could be
important steps towards reducing natural enemies̓ rearing costs. Nutritional values of four factitious
foods comprising Ephestia eggs, decapsulated Artemia cysts, mould mite immature individuals, and
Aspergillus hyphae as alternative food sources for Neoseiulus californicus (McGregor) were determined
under laboratory conditions. In addition, suitability of artificial (plastic sheet) and leaf-based substrates
for rearing of the predator was assessed. The duration of egg to adult developmental time was shorter
when the predator fed on the mould mite compared with the other diets. Artemia cysts and Aspergillus
hyphae were not suitable diets. The individuals reared on the mould mite had the highest fecundity and
intrinsic rate of increase (r). Due to weak mouthpart of the immature predator in feeding of factitious
foods, most of them died in immature stages, or their fecundity in adult stage was low. In a separate
experiment, almond pollen was also used in addition to factitious foods for rearing of immature stages of
the predator. The adult stage of these individuals had the ability to feed and oviposit on the factitious
foods, and female longevity and fecundity of these individuals were higher on E. kuehniella egg (and
after that on mould mite) than the others. In addition, the results indicated that the rearing performance
of the predator fed on the same diet was higher on the artificial substrate than the leaf-based one. The
potential of alternative foods and artificial substrates for mass production and conservation of
N. californicus is a suitable and cheap method.