2. INTRODUCTION, AUGMENTATION
AND CONSERVATION OF
NATURAL ENEMIES
Guided to
Dr.M.K.Nayak
Presented by
Rahul patidar
Roll No.-5776
DEPARTMENT OF ENTOMOLOGY
KRISHI MAHA VIDYALAYA, TIKAMGARH, (M. P.)
3. The following ecological points to be considered for
successful natural enemy introduction –
The natural enemy should be imported from a place
having similar climate.
It should be free from alternate hosts.
It should be free from hyper parasitoids and other
biological competitors for the hosts.
Physiological suitability of the natural enemy to its
hosts and suitability of the host plant ecosystem.
Imported natural enemy should have low dipersal.
4. It includes all activities designed to increase
number or effect of existing natural enemies.
These objectives may be achieved by releasing
additional number of natural enemies into a
system or modifying the environment I such a
way as to promote greater number or
effectiveness.
5. There are two types-
1) Inoculative releases ;-
These may be made as infrequently as once as
once in a year to reestablish natural enemy. Here control
is expected from the progeny and subsequent generations
and not from the release itself.
2) Inundactive releases ;-
It involves mass culture and release of natural
enemies to suppress the pest population directly. These
are effective against pests having one or a few discrete
generation every year. Here the control from release itself.
6. Conservation
Conservation of bio- control agent can be achieved by;-
a) Rationalizing use of pesticides – pesticides
affect the natural enemies by repelling or reducing the
longevity, fecundity and searching ability and decimating
the population of the flying adult.
These can be avoided by –
Use of non- persistent pesticide,
Use of safe and selective pesticide,
Use of minimum recommended dose,
Use of microbial pesticide instead of synthetic pesticide.
7. b)Providing food and shelter –
Nesting boxes and bird perches act suitable sites and
encourages build up of predators.
Pollen and nectar bearing flowering plants are planted on
the bunds to provide supplementary food to predators.
c)Suppression of ants ;-
Suppression of ants or their physical exclusion increase
the efficiency of predators.
8. d) Beneficial management practices ;-
Chisel ploughing conserve natural enemies of
inhabiting pests.
Use of manures conserves predaceous arthropods
and soil borne microbial antagonists of insect
pests.
Manipulation of relative humidity and wetting
periods enhances the efficiency of entomo fungal
pathogen.
9. e) Determining the need for action ;-
The time and period of natural enemy should
synchronize with the availability of suitable stage of
the pest.
When parasitoids are active predators should not be
released similarly when entomo pathogen are active
parasitoids should be released for effective control.
f) Trap cropping ;-
Growing of trap crops along with the main crop
increase the overall efficiency of parasitoids and
several predators.