Authors: Umar Niaz, , Burhan Ahmad, , Department of Entomology
University of Agriculture Faisalabad, Pakistan.
Introduction:
There is a large population of insect pests which are present the earth, in this
population various insects are not dangerous for agricultural crops because they are beneficial to
crops and farmer and fight for crop production against harmful insect pests. Now a days farmers
are used chemicals continuously to gain high production or yield. Continuous use of these harmful
chemicals affect environment, natural enemies (predators, parasitoids, and parasites), human
health and other non-target organisms.
Resistance can be also produced in insect pests against pesticides by using chemicals
again and again. Biological control is also known as classical control for insect pest’s .It is very
significant tool to control target pests naturally in integrated Pest management. One reason is
behind to use large number of chemicals is the lack of awareness about biological or natural
control. So farmers should be aware to know positive and negative impact of natural control.
Some Tools which are used for Natural Control:
Predators:
Those organisms which depend on host for food and survive by preying host
organisms. Total 40 families which are used as a predator to prey insect pests such as
Anthocoridae, pentatomidae, reduviidae, carabide, syrphidae and vellidae etc.
Parasites:
Those organisms which live on living host and get feed from their host and cause death.
10% species are parasitoids
43 families –Hymenoptera are parasitoids
12 families-Diptera are parasitoids
Recent research have been proved that 26 families which are used in natural control pests.
Bacteria:
Eubactariales, Bacillus (bacillaceae, serratia) from family (bacilliaceae) Bacillus thuringensis
(Bt) using widely as a biotech control.
Virus:
Granulosis Viruses, Nuclear Polyhedrosis Viruses (NPV) and Baculovirus
Fungi:
Zygomycotina, Mastigomycotina,and Deutromycotina
Merits and Demerits of Biotic Control:
Merits:
Due to natural control against insect’s pests we can save our environment, health, on- target
organisms from hazard effects of synthetic chemicals.
It’s not a need of long time, heavy effort and large number of laborers and cost while
farmers spend more money for spraying.
It is cost effective, classical and specific target pest control which is not injurious for human
health and other non-target organisms.
In case of fruit trees, Fruit will not be damage by biotic or natural control.
It can be applied under green house or glasshouse conditions
Demerits:
Various unknown species present
If the pests not present then natural enemies cannot survive
It’s a slow process instead of synthetic chemical pest control
It’s a costly and requires high expertise and skills if we rear natural enemies.
It requires a large area for implementation