ratio of 1–20 per one (Attaran and Dadpour-Moganlou 2011). Because A. kuehniella
can be easily used for mass rearing of Habrobracon hebetor Say as well, requires
minimal rearing facilities and is suitable enough for wasps, can be considered in
Trichogramma mass rearing systems. Nevertheless due to higher labor required,
should be improved. More than 517 kg parasitized eggs of S. cereallella were
purchased by Plant Protection Organization of Iran from manufacturers of
Trichogramma in 2011 (Attaran and Dadpour-Moganlou 2011). In the current
mass rearing system in Iran, production efficiency is three per one. In order to
increase efficiency and have a cost-effective production, one have to choose the
higher quality hosts and thelytokous Trichogramma populations with higher tolerance to temperature and pesticide-resistant ones.
6.6 Quality Control and Parasitoid Efficacy Studies
One challenging object in mass-rearing of Trichogramma spp. in Iran is quality
control of the produced wasps. Quality control is a process that begins with choosing
agents for initiating mass culture and continues to final steps of efficacy evaluation.
The most common definition of mass production is easy way of rearing of large
number of insects over the existing number to use in control unit (Shorey and Hale
1965). Several criteria are used in monitoring the quality of the produced agents to
ensure continuity of production. Criteria such as viability, survival rate, adult size,
density dependence, performance, sex ratio, life span and adaptation to environmental conditions. Dutton et al. (1996) divided the qualitative factors of trichogrammatid
production in two categories. First-one is parameters affecting the number of
released females such as percentage of adult emergence, percentage of malformed
females and sex ratio. The second one is suitability and preference parameters of
trichogrammatids, such as longevity and fertility both on factitious and target hosts,
acceptability and suitability of target host for parasitoids that developed on factitious
host and flight ability. According to Etzel and Legner (1999) the most important
factor in mass rearing is fertility. The main factor limiting widespread use of
Trichogramma on a global scale is lack of necessary information on the quality of
produced Trichogrammatidae (Losey and Calvin 1995).
The International Organization of Biological Control (IOBC) has offered standards for mass rearing of Trichogramma spp. The sex ratio above 50%, fertility rate
above 40 progeny per week, female mortality below 20% after 7d, parasitized at least
10 host eggs within 4 h, adult emergence above 80% and malformed females below
5% are standard indices of trichogrammatids in this instruction (Bigler et al. 1991;
Singh et al. 2001; van Lenteren 2003). A comprehensive quality control guideline
has not been published in Iran yet. However, problem is not lack of information but
is rather its implementation. A qualitative evaluation of Iranian insectaries in 2006
showed that 30–40% of them are out of a standard range. An evaluation revealed that
it is mainly due to low percentage of adult emergence as well as high percentage of
malformed females (Shirazi et al. 2006). Low rate of adult emergence can be caused
6 Egg Parasitoids: Chalcidoidea with Particular Emphasis on Trichogrammatidae
207
can be easily used for mass rearing of Habrobracon hebetor Say as well, requires
minimal rearing facilities and is suitable enough for wasps, can be considered in
Trichogramma mass rearing systems. Nevertheless due to higher labor required,
should be improved. More than 517 kg parasitized eggs of S. cereallella were
purchased by Plant Protection Organization of Iran from manufacturers of
Trichogramma in 2011 (Attaran and Dadpour-Moganlou 2011). In the current
mass rearing system in Iran, production efficiency is three per one. In order to
increase efficiency and have a cost-effective production, one have to choose the
higher quality hosts and thelytokous Trichogramma populations with higher tolerance to temperature and pesticide-resistant ones.
6.6 Quality Control and Parasitoid Efficacy Studies
One challenging object in mass-rearing of Trichogramma spp. in Iran is quality
control of the produced wasps. Quality control is a process that begins with choosing
agents for initiating mass culture and continues to final steps of efficacy evaluation.
The most common definition of mass production is easy way of rearing of large
number of insects over the existing number to use in control unit (Shorey and Hale
1965). Several criteria are used in monitoring the quality of the produced agents to
ensure continuity of production. Criteria such as viability, survival rate, adult size,
density dependence, performance, sex ratio, life span and adaptation to environmental conditions. Dutton et al. (1996) divided the qualitative factors of trichogrammatid
production in two categories. First-one is parameters affecting the number of
released females such as percentage of adult emergence, percentage of malformed
females and sex ratio. The second one is suitability and preference parameters of
trichogrammatids, such as longevity and fertility both on factitious and target hosts,
acceptability and suitability of target host for parasitoids that developed on factitious
host and flight ability. According to Etzel and Legner (1999) the most important
factor in mass rearing is fertility. The main factor limiting widespread use of
Trichogramma on a global scale is lack of necessary information on the quality of
produced Trichogrammatidae (Losey and Calvin 1995).
The International Organization of Biological Control (IOBC) has offered standards for mass rearing of Trichogramma spp. The sex ratio above 50%, fertility rate
above 40 progeny per week, female mortality below 20% after 7d, parasitized at least
10 host eggs within 4 h, adult emergence above 80% and malformed females below
5% are standard indices of trichogrammatids in this instruction (Bigler et al. 1991;
Singh et al. 2001; van Lenteren 2003). A comprehensive quality control guideline
has not been published in Iran yet. However, problem is not lack of information but
is rather its implementation. A qualitative evaluation of Iranian insectaries in 2006
showed that 30–40% of them are out of a standard range. An evaluation revealed that
it is mainly due to low percentage of adult emergence as well as high percentage of
malformed females (Shirazi et al. 2006). Low rate of adult emergence can be caused
6 Egg Parasitoids: Chalcidoidea with Particular Emphasis on Trichogrammatidae
207