the produced parasitoids have been released in thousands of hectares in different
crops (Liu et al. 1995). One of the major limiting factors may be the still lower
quality of most of the natural enemies reared with artificial diets when compared to
the same ones reared with factitious preys, but a few exceptions have been
published with high potential to be scaled up by the industry. The needed protection
of results when companies are involved (secrecy, competition, patents, etc.) also
delay the exchanges between researchers and slow down the improvements.
Finally, automatism process, which has deserved less attention by academics, is a
significant step for the industry.
An option for the biomanufacturers is the use of artificial diets not to completely substitute the factitious preys, but just a part of the diets, mixing it with the
prey or just using it in specific stages of the predator. Not only important economical savings have been achieved without losing final quality of the insects, but
also improvements of biological parameters of generalist predators have been
accomplished with the mixtures of complementary non-arthropod diets together
with Ephestia eggs on industrial productions, according to results obtained by the
authors of this chapter. Other authors have also highlighted the benefits that
feeding generalists predators with a mixed diet could have on reproduction (Evans
et al. 1999; Leon-Beck and Coll 2007; Michaud and Jyoti 2008; Urbaneja-Bernat
et al. 2012).
Generalist predators have been stated to be more suitable for being reared
successfully using artificial diets, and certainly the best achievements obtained on
industrial processes are with this generalist entomophaga. In this chapter attention
will be focused on the latest improvements accomplished on rearing systems of the
main generalist predators that are released on greenhouses in Almeria, as well as in
other growing areas of protected vegetables in Europe. Specifically, attention is
played to species belonging to the families Miridae, Anthocoridae, and the predatory mites Phytoseidae. The last ones have deserved little or no attention in the
previous reviews published about factitious preys and artificial diets, even that
they represent a significant number of the predators released by commercial
producers. Moreover, Phytoseidae are the key natural enemies in several crops and
after the latest mass rearing improvements they have a big potential as biocontrol
agents for many crops, including open fields and, in general, crops that suffer of a
low profit margin.
4.4 Predatory Mites
Currently, all commercially used in large quantities phytoseiid mite predators are
reared ex-plant, not on their preferred pest species but with factitious preys, except
Phytoseiulus persimilis Athias-Henriot (Acari: Phytoseiidae) which is reared on
plants with spider mites. The factitious preys are commonly a member of one of a
few families of mites from the order Astigmata. These are small, soft-bodied
individuals, known as ‘stored food mites’ or ‘stored product mites’ and as such live
4 Biosystems Engineering Applied to Greenhouse Pest Control
115
crops (Liu et al. 1995). One of the major limiting factors may be the still lower
quality of most of the natural enemies reared with artificial diets when compared to
the same ones reared with factitious preys, but a few exceptions have been
published with high potential to be scaled up by the industry. The needed protection
of results when companies are involved (secrecy, competition, patents, etc.) also
delay the exchanges between researchers and slow down the improvements.
Finally, automatism process, which has deserved less attention by academics, is a
significant step for the industry.
An option for the biomanufacturers is the use of artificial diets not to completely substitute the factitious preys, but just a part of the diets, mixing it with the
prey or just using it in specific stages of the predator. Not only important economical savings have been achieved without losing final quality of the insects, but
also improvements of biological parameters of generalist predators have been
accomplished with the mixtures of complementary non-arthropod diets together
with Ephestia eggs on industrial productions, according to results obtained by the
authors of this chapter. Other authors have also highlighted the benefits that
feeding generalists predators with a mixed diet could have on reproduction (Evans
et al. 1999; Leon-Beck and Coll 2007; Michaud and Jyoti 2008; Urbaneja-Bernat
et al. 2012).
Generalist predators have been stated to be more suitable for being reared
successfully using artificial diets, and certainly the best achievements obtained on
industrial processes are with this generalist entomophaga. In this chapter attention
will be focused on the latest improvements accomplished on rearing systems of the
main generalist predators that are released on greenhouses in Almeria, as well as in
other growing areas of protected vegetables in Europe. Specifically, attention is
played to species belonging to the families Miridae, Anthocoridae, and the predatory mites Phytoseidae. The last ones have deserved little or no attention in the
previous reviews published about factitious preys and artificial diets, even that
they represent a significant number of the predators released by commercial
producers. Moreover, Phytoseidae are the key natural enemies in several crops and
after the latest mass rearing improvements they have a big potential as biocontrol
agents for many crops, including open fields and, in general, crops that suffer of a
low profit margin.
4.4 Predatory Mites
Currently, all commercially used in large quantities phytoseiid mite predators are
reared ex-plant, not on their preferred pest species but with factitious preys, except
Phytoseiulus persimilis Athias-Henriot (Acari: Phytoseiidae) which is reared on
plants with spider mites. The factitious preys are commonly a member of one of a
few families of mites from the order Astigmata. These are small, soft-bodied
individuals, known as ‘stored food mites’ or ‘stored product mites’ and as such live
4 Biosystems Engineering Applied to Greenhouse Pest Control
115