This document discusses herbal pesticides as an alternative to synthetic pesticides. It defines pesticides and notes that herbal pesticides are derived from plants and herbs, having lower toxicity than synthetic pesticides. Some key herbal pesticides discussed include neem, tobacco, chili, and citronella. The document compares herbal and synthetic pesticides, noting advantages of herbal pesticides like being less toxic, more selective, and less harmful to the ecosystem. It concludes that as concerns rise over synthetic pesticides, the world is shifting toward more natural crop protection using herbal pesticides.

1. A Review On
--HERBAL PESTICIDES--
BY –DIPANKAR DUTTA
B. Pharm 4th year
DEPARTMENT OF PHARMACEUTICAL SCIENCES
ASSAM UNIVERSITY, SILCHAR

2. Definition of Pesticides
Pesticides are chemical compounds that are used to kill pests,
including insects, rodents, fungi and unwanted plants (weeds).
Pesticides are used in public health to kill vectors of disease, such
as mosquitoes, and in agriculture, to kill pests that damage crops.
HERBAL PESTICIDES
Herbal pesticides are derived or extracted from plant or herbs. They are
having very much low side effect to the human body as well as the eco
system in comparison to synthetic pesticides.

3. Significance of selecting Herbal pesticides:-
 Herbal pesticides are usually inherently less toxic than conventional pesticides.
 Herbal pesticides generally affect only the target pest and closely related organisms, in
contrast to broad spectrum, conventional pesticides that may affect organisms as
different as birds, insects and mammals.
 Herbal pesticides often are effective in very small quantities and often decompose
quickly, resulting in lower exposures and largely avoiding the pollution problems caused
by conventional pesticides.
 Herbal pesticides are environment friendly.
 Systematic don’t attack the host organism.
 Easily bio degradable and don’t possess any toxic effects.
 Do not having any dosage problems as their drugs tolerance limit is very high.
 May also be tried by mixing with one or more botanicals or the synthetic organic
compounds (synergistic effect) and such combination may be more effective.
 Many synthetic pesticides are carcinogenic it may causes cancer, but herbal pesticides are
relatively safe.

4. HERBL PESTICIDES SYNTHETIC PESTICIDES
They don’t develop resistance to pesticides They accelerated the development of genetic resistance to pesticides
They are selective They are not selective
The ecosystem is less effected The ecosystem is very much effected
No such harmful residues remains in food, fodder and fibers. Many harmful residues remains in food, fodder and fibers
They are less stable They are more stable
Narrow spectrum of activity Broad spectrum of activity
Slow action; residues may not be accumulate Fast action; residues may be accumulate
COMPARISON BETWEEN HERBAL AND SYNTHETIC PESTICIDES
Benefit of Herbal pesticides:-
 Rapid degradation : This characteristic, although desirable in some respect, creates a need for
precise timing or more frequent applications
 Toxicity: All toxins used in pests control pose some hazarded to the user and to the
environment.
 Lack of test data: Data of effectiveness of long term (chronic) toxicity are unavailable for some
botanicals and tolerances for some have not been properly established.

5. Pharmaceutical dosage forms of various Herbal pesticides:-
They are processed into various forms –
 Preparation of crude plant material
 Plant extract
 Pure chemical isolated from the plant
Generally Herbal pesticides are used in various dosage forms i.e. spray, paste, suspension, dust, emulsion
& sometime they are marketed in the form of aerosols and gas propellants. For the application of the
Herbal pesticides dosages forms small hand spray, small brush for use in home to large powder sprays for
livestock’s and field crops. For vast area dispersal airplanes and helicopters are used.
Essential of good Herbal pesticides:-
It should be a high margin of safety for plants and animals casing a very
little or no damage to the foliage or live stocks respectively.
It should be safe.
It should be easier to handle and easy for the applications.
It should not show toxicity.
It should not be inflammable or explosive.

7. Neem ( Azadirachta Indica )
Family – MALINACEAE
part used – leaf
botanical description – India , Nepal , Pakistan ,
Chemical compounds -
Azadirachtin , Nimbin , Nimbidin , Nimbidol, Quercitin, ,
, Asorbic acid, β- sitosterol ,
Some marketed Neem pesticides
Nicotiana glauca (tobacco)
Color: - Green or slightly brown
Odor: - Characteristic to Nicotine
Taste: - Bitter
Size: - 60 – 80 cm. in length, 35 – 45 cm.in
Shape: - Ovate, elliptic or lanceolate
Chemical compounds
piperidine type of alkaloid, nicotine. The other
alkaloids are nor- nicotine and anabasine.
Some marketed tobacco pesticides

8. Capsicum frutescens (chili)
Family – NIGHTSHADE
Part used- fruit
Botanical description – India , Bangladesh , Nepal
Chemical compounds:
capsaicinoids( responsible for hotness ) & ascorbic acid, zinc,
phosphorous, copper are also present in chili.
Some marketed chilli pesticides
Cymbopogon nardus (citronella )
Family :- CARDIOPTERIDASE
Part used :- from leaf oil is extracted
Botanical description – India , Bangladesh , Nepal
Chemical compounds:-
volatile oil, geraniol and citronellal Others constituents
borneol, linalool, methyl eugenol. Recently it is found to
have cadinene and elmicin.
Some marketed citronella pesticides

9. Conclusion
It is noticed by the farming community and agricultural scientist that amount
of using pesticides is increasing day by day in the agriculture. But by the
using of various unsafe synthetic pesticides it gives a very harmful effect on
the human health and as well as the ecosystem. Today’s agriculture
demands practice of modern techniques coupled with scientific
management. This will help getting more yield of better quality resulting into
better revenue and profit. So the entire world is now shifting towards
natural crop protection i.e. for the use of herbal pesticides.