Lesser to interrupt insect’s growth and development. Keeping

Lesser grain borer, Rhyzopertha
dominica (F.), is another severe pest of wheat grains during storage and is
also having a worldwide dissemination. The origin of R. dominica is not
certain, but is believed to be originated from Indian subcontinent (Potter
1935). R. dominica is also highly
polyphagous in nature. R.
dominica is a very small
cylindrical beetle with dark brown colour and shiny in appearance. One of the
characteristic feature of these beetles are there deflexed head, which is not
visible from above. Female lays eggs either singly or in small groups
peripheral to the grain; eggs may be placed loosely among the grains or
attached to a kernel. Total life cycle varies with temperature and humidity
conditions, taking on an average 25 days at 34 °C and 70% RH. Larval period is completed
within 16 days under optimum temperature and humidity conditions (Birch, 1945).
Male can be distinguished from females in having pale yellowish colour on the
ventral side (Jagadish et al., 2009). A yield
loss of 17% and 23% has been reported per wheat kernel by Campbell and Sinha
(1976) and Crombie (1944) respectively.
The foremost challenge in stored product insect management is their faster
multiplication rate. They are not only consuming the last produce but also
detoriating the quality by their excreta, bad odour and flavours (Atwal, 1986).

Physical
as well as the biochemical properties of food are known to affect the
developmental rates of insects. An accurate information on variation of insect
developmental rate with the change in grain parameters would be valuable in
finding the biological factors responsible for insect resistance. Nowadays,
biological and physical methods are getting widely accepted as alternatives for
perilous chemical pesticides which are used for the management of stored insect
pests (Nawrot et al., 2006).

Also
the insect digestive enzymes are a probable target for reducing insect feeding.
Carbohydrases, proteases
and lipases are the three core digestive enzymes involved in digestion process.Wheat
is a significant source of polysaccharides, proteins and lipids The insect pest
of stored grain depend on the potency of their digestive enzymes for digestion.
Thus the use of digestive enzyme inhibitors is a promising method to interrupt
insect’s growth and development.

 Keeping in view the importance of wheat grains
and damage by pests, studies is aimed on the resistance of different wheat
genotypes to Sitophilus oryzae and Rhyzopertha dominica with the
following objectivesLesser grain borer, Rhyzopertha
dominica (F.), is another severe pest of wheat grains during storage and is
also having a worldwide dissemination. The origin of R. dominica is not
certain, but is believed to be originated from Indian subcontinent (Potter
1935). R. dominica is also highly
polyphagous in nature. R.
dominica is a very small
cylindrical beetle with dark brown colour and shiny in appearance. One of the
characteristic feature of these beetles are there deflexed head, which is not
visible from above. Female lays eggs either singly or in small groups
peripheral to the grain; eggs may be placed loosely among the grains or
attached to a kernel. Total life cycle varies with temperature and humidity
conditions, taking on an average 25 days at 34 °C and 70% RH. Larval period is completed
within 16 days under optimum temperature and humidity conditions (Birch, 1945).
Male can be distinguished from females in having pale yellowish colour on the
ventral side (Jagadish et al., 2009). A yield
loss of 17% and 23% has been reported per wheat kernel by Campbell and Sinha
(1976) and Crombie (1944) respectively.
The foremost challenge in stored product insect management is their faster
multiplication rate. They are not only consuming the last produce but also
detoriating the quality by their excreta, bad odour and flavours (Atwal, 1986).

Physical
as well as the biochemical properties of food are known to affect the
developmental rates of insects. An accurate information on variation of insect
developmental rate with the change in grain parameters would be valuable in
finding the biological factors responsible for insect resistance. Nowadays,
biological and physical methods are getting widely accepted as alternatives for
perilous chemical pesticides which are used for the management of stored insect
pests (Nawrot et al., 2006).

Also
the insect digestive enzymes are a probable target for reducing insect feeding.
Carbohydrases, proteases
and lipases are the three core digestive enzymes involved in digestion process.Wheat
is a significant source of polysaccharides, proteins and lipids The insect pest
of stored grain depend on the potency of their digestive enzymes for digestion.
Thus the use of digestive enzyme inhibitors is a promising method to interrupt
insect’s growth and development.

 Keeping in view the importance of wheat grains
and damage by pests, studies is aimed on the resistance of different wheat
genotypes to Sitophilus oryzae and Rhyzopertha dominica with the
following objectives