helped create a progress in life table studies and many Iranian researchers rearrange
their studies based on this new analysing method. However, still, there are some
publications that use the traditional female-based method. In this period, many
similar studies evaluated different suitability of aphids or even other prey (Pistachio
psylla) (Mehrnejad et al. 2011) to the development and survival of H. variegata. One
of the serious deficiencies of life history studies of lady beetles is that nearly all of
them have been conducted under very artificial conditions, at constant temperature
and humidity. Obviously, these results could not be extrapolated to real conditions
and need to be validated. Most of these invesstigations have been done at 25 Æ 1
C,
but a few researchers tested different temperatures too.
Like functional response studies, an important part of life history researches has
been devoted to variegated lady beetle species as an ubiquitous dominant species in
Iran. For conciseness, demographic values of different species of genus Hippodamia
were summarized in Table 2.1 separately. Mollashahi et al. (2002) reported the life
table parameters of H. variegata by feeding on melon aphids. Mollashahi et al.
(2004a) revealed that the product index of H. variegata and C. septempunctata could
be influenced by temperature and prey species; as such, this index of both species
was highest at 30
C when that were fed on Aphis craccivora. Studying the
temperature - dependent development of H. variegata revealed that the minimum
temperature threshold needed for growth of first instar larvae and pupae was 2.47
and 14.63, respectively. Furthermore, this species needs 346.4 degree- days (DD) to
complete its development (Jafari and Vafaei Shoushatri 2010).
Stored moth egg as factitious prey has been suggested for the rearing of different
lady beetle species. It has been stated that the Mediterranean flour moth was the best
diet for rearing and mass production of Pharoscymnus ovoideus (Hajizadeh 1993).
Furthermore, Tavoosi Ajvad et al. (2011) showed that H. variagata could complete
its life cycle on Mediterranean flour moth (MFM) eggs and adult longevity on cotton
aphids, pea aphids and Ephestia kuehniella were 53.83, 52.43 and 67.75 days. Thus
the use of MFM eggs reduced the use of natural prey and labor needed.
Recently, tritrophic relationships became as a significant field of interest for
Coccinellids studies and many researchers studied the basic biology of ladybirds
under this context. In a tritrophic study, it was proved that host plant resistance could
be effective on consumption rate of C. septempunctata and resulted in higher feeding
rate of adults than feeding on aphids on susceptible crops (Barkhordar et al. 2012).
Ghafouri Moghaddam et al. (2013) showed the premature period and survival of
H. variegata significantly influenced by host plants. Thus, the Sitobion avenae
Fabricius reared on wheat was more profitable for this lady beetle species. Similarly,
it has been shown that Mustard plants affected on laboratory biology of this lady
beetle via feeding on cabbage aphid (Nikan Jablou et al. 2013). Accordingly,
the suitability of cereal aphids reared on different host plants for mass rearing of
H. variegata has been evaluated by a few studies. Asgharian et al. (2014) showed the
higher suitability of barley for this species among the four host plant tested of
Russian wheat aphid. Another related research considered the effect of two resistant
and susceptible wheat cultivars to Diuraphis noxia (Kurdjumov) on basic biology
and life history of H. variegata (Zanganeh et al. 2015). They found a
2 Lady Beetles; Lots of Efforts but few Successes
45
their studies based on this new analysing method. However, still, there are some
publications that use the traditional female-based method. In this period, many
similar studies evaluated different suitability of aphids or even other prey (Pistachio
psylla) (Mehrnejad et al. 2011) to the development and survival of H. variegata. One
of the serious deficiencies of life history studies of lady beetles is that nearly all of
them have been conducted under very artificial conditions, at constant temperature
and humidity. Obviously, these results could not be extrapolated to real conditions
and need to be validated. Most of these invesstigations have been done at 25 Æ 1
C,
but a few researchers tested different temperatures too.
Like functional response studies, an important part of life history researches has
been devoted to variegated lady beetle species as an ubiquitous dominant species in
Iran. For conciseness, demographic values of different species of genus Hippodamia
were summarized in Table 2.1 separately. Mollashahi et al. (2002) reported the life
table parameters of H. variegata by feeding on melon aphids. Mollashahi et al.
(2004a) revealed that the product index of H. variegata and C. septempunctata could
be influenced by temperature and prey species; as such, this index of both species
was highest at 30
C when that were fed on Aphis craccivora. Studying the
temperature - dependent development of H. variegata revealed that the minimum
temperature threshold needed for growth of first instar larvae and pupae was 2.47
and 14.63, respectively. Furthermore, this species needs 346.4 degree- days (DD) to
complete its development (Jafari and Vafaei Shoushatri 2010).
Stored moth egg as factitious prey has been suggested for the rearing of different
lady beetle species. It has been stated that the Mediterranean flour moth was the best
diet for rearing and mass production of Pharoscymnus ovoideus (Hajizadeh 1993).
Furthermore, Tavoosi Ajvad et al. (2011) showed that H. variagata could complete
its life cycle on Mediterranean flour moth (MFM) eggs and adult longevity on cotton
aphids, pea aphids and Ephestia kuehniella were 53.83, 52.43 and 67.75 days. Thus
the use of MFM eggs reduced the use of natural prey and labor needed.
Recently, tritrophic relationships became as a significant field of interest for
Coccinellids studies and many researchers studied the basic biology of ladybirds
under this context. In a tritrophic study, it was proved that host plant resistance could
be effective on consumption rate of C. septempunctata and resulted in higher feeding
rate of adults than feeding on aphids on susceptible crops (Barkhordar et al. 2012).
Ghafouri Moghaddam et al. (2013) showed the premature period and survival of
H. variegata significantly influenced by host plants. Thus, the Sitobion avenae
Fabricius reared on wheat was more profitable for this lady beetle species. Similarly,
it has been shown that Mustard plants affected on laboratory biology of this lady
beetle via feeding on cabbage aphid (Nikan Jablou et al. 2013). Accordingly,
the suitability of cereal aphids reared on different host plants for mass rearing of
H. variegata has been evaluated by a few studies. Asgharian et al. (2014) showed the
higher suitability of barley for this species among the four host plant tested of
Russian wheat aphid. Another related research considered the effect of two resistant
and susceptible wheat cultivars to Diuraphis noxia (Kurdjumov) on basic biology
and life history of H. variegata (Zanganeh et al. 2015). They found a
2 Lady Beetles; Lots of Efforts but few Successes
45