2. ENTO 231 (2+1):FUNDAMENTALS OF
ENTOMOLOGY-II and IPM
Course In-Charge
Mr.S.Srinivasnaik
Assistant Professor
Department of Entomology
LECTURE NO.12
BOTANICAL INSECTICIDES
3. BOTANICAL INSECTICIDES
There are different groups of plants comes under kingdom
plantae.
•Bryophytes: 15,600 species
•Pteridophytes: Eg: Ferns: 11,000 species
•Gymnosperms: Eg: Conifers : 760 species
•Angiosperms –flowering plants: 2,35,000 species.
In India 17,527 species, 296 sub species, 2215 varities,
33 sub varities, 70 forma and 20,141 taxa of angiosperms
under 2991 genera and 257 families.It constitutes 7% of the
species in the world.
4. BOTANICAL BIOPESTICIDES
Among all 2,400 plant species are reported to have pesticidal
properties. Most promising botanical pesticides for use are
present in substances derived from species of the families
Meliaceae, Rutaceae, Asteraceae, Labiatae and canellaceae.
The single most important botanical source of pesticidal
compounds is Azadirachta indica, belongs to family meliaceae.
Azadirachtin a tetranotriterpenoid isolated from the neem tree is
found to be effective as a feeding deterrent, repellent, toxicant,
sterilant and growth disruptant.
5. BOTANICAL BIOPESTICIDES
Plant family Number of plants having
pesticidal property
Meliaceae >500
Myrtaceae 72
Asteraceae 70
Ephorbiaceae 65
Leguminosae 60
Fabaceae 55
Important families having pesticidal properties are
7. BOTANICAL BIOPESTICIDES
Major botanical products:
•Pyrethrum
•Rotenone
•Neem
•Essential oils
Others in limited use
•Ryania
•Nicotine
•Sabadilla
Additional plant extracts and oils
•Garlic oils
•Capsicum oleoresin
8. BOTANICAL BIOPESTICIDES
1.Indian neem tree
•Neem is native to India and Burma
•The active ingradients is a mixture of Azadirachtin, melantriol, salannin,
nimbin and nimbidin and these all belong to group of tetranotriterpenoid
•The main active ingradient that has potential insecticidal activity present in
neem is azadirachtin, which is present in seeds and leaves and it varies
from 2-4 mg/g kernal
•Azadirachtin has several stereoisomers but so far 7 stereoisomers have
been reported viz., AZA (A-G). Azadirachtin A constitutes 85% followed
by Azadirachtin B almost 14%
9. BOTANICAL BIOPESTICIDES
•Neem has various effects on insects viz., antifeedant action, insect growth
regulatory activity inhibits juvenile hormone synthesis, oviposition deterrent,
repellent action, reduction of life span of adults and intermediates are formed giving
rise to larval-pupal, nymphal-adults and pupal-adults intermediates.
•Neem based products are sensitive to UV light i.e., they degrade when exposed to
sunlight
•Different concentrations of Azadirachtin both neem kernel based EC, Oil, and
concentrate based are registered in India; 0.15%, 0.3%, 1%, 0.03% and 5%.
•The commercial insecticides of neem available in market are based on neem seed
kernel extract (NSKE) some of products are commonly used are Gronim, Neemazal,
Achook, Nimbecedine.
10. BOTANICAL BIOPESTICIDES
2. Rotenone
•It is resin derived from roots of leguminous plants Lonchocarpus
spp. (South American plant) and Derris eliptica (Malaysia)
•It is a broad spectrum and stomach poison
•It effects nerve and muscle cells in insects ab sometimes
causes insects to stop feeding
•It inhibits respiratory metabolism
•It is used as dusts containing 0.75-1.5% rotenone and effective
against beetle and caterpillars
•It is extremely toxic to fish
11. BOTANICAL BIOPESTICIDES
3. Sabadilla
•It is an alkaloid found in seeds of tropical lily, Schoenocaulon
officinale (Family:Liliaceae)
•The alkaloids mainly ceyadine and veratridine act as nerve
poisons
•It is a primarily contact poison
•Sabadilla is harmful to pollinators and honey bees
12. BOTANICAL BIOPESTICIDES
5. Ryanodine
•It is an alkaloid derived from woody stems of South American
shrub, Ryania speciosa (Family: Flacourtaceae)
•It acts as muscular poison by blocking the conversion of ADP
to ATP in striated muscles
•It acts as slow acting stomach poison and causes insects to stop
feeding after they eat it
•It is reportedly effective against thrips and worms
•It is used as dust (20-40%)
13. BOTANICAL BIOPESTICIDES
6. Nicotine
•Nicotine is obtained from tobacco plants, Nicotiana tobaccum,
N. rustica (Family: Solanaceae)
•Activity: Mimics acetylcholine in the nerve synapse causing
tremors, loss of coordination and eventually death.
•It is extremely fast acting, causing sever disruption and
failure of nervous system
•Sold commercially as a fumigant Nicotine or as a dust
(Nicotine Suphate)
•It is commercially avaible as nicotine sulphate 40 % (Black
Leaf 40) and manufactured in India only for export purpose
•It acts as contact poison
•It is effective against soft bodied sucking insects like thrips,
leafhoppers, mealybugs and leaf miners
14. BOTANICAL BIOPESTICIDES
7. Pyrethrum
•Pyrethrum refers to powdered dried flowers of Chrysanthemum
cinerarifolium and pyrethrins are all toxic constituents of the pyrethrum flowers
and pyrethroids are the synthetic analogues of pyrethrins
•Pyrethrum is occupied 80% global botanical insecticide market
•Chrysanthemum cinerarifolium is native of Dalmatian mountains, Croatia
•Kenya is a largest producer of pyrethrum
•Pyrethrins are esters formed by combination of two acids i.e., chrysanthemic
acid and pyrethric acid with three alcohols namely pyrethrolone, cinerolone
and jasmolone. The esters of chrysanthemic acid are pyrethrin I, Cinerin I
and Jasmolin I and are combined together known as pyrethrins I. The esters
of pyrethric acid are pyrethrin II, Cinerin II and jasmolin II and are together
known as pyrethrins II. These six active principles together are responsible for
toxicity and knockdown action.
15. BOTANICAL BIOPESTICIDES
Pyrethrins Acid Alcohol
Pyrethrin I Chrysanthemic acid Pyrethrolone
Pyrethrin II Pyrethric acid Pyrethrolone
Cinerin I Chrysanthemic acid Cinerolone
Cinerin II Pyrethric acid Cinerolone
Jasmolin I Chrysanthemic acid Jasmolone
Jasmolin II Pyrethric acid Jasmolone
16. BOTANICAL BIOPESTICIDES
•Pyrethrins mode of action is similar to DDT and has fast acting knock down
effect
•It breaks down quickly from sunlight
•The commonly used synergist to synergies pyrethrins is piperonyl butoxide
(PBO)
The major pyrethrins producing species are:
•Chrysanthemum cinerarifolium
•Chrysanthemum cocineum
•Chrysanthemum roseum
•Chrysanthemum marshal
•Chrysanthemum tamrentene
The pyrethrins extracted are photodegradable. In order to keep stability
in the structure of the pyrethrins the molecular formula observed and
substituted with different molecules
17. BOTANICAL BIOPESTICIDES
Pyrethrins Pyrethroids
These are active chemicals in
pyrethrum and are 100 % natural
These are synthetic /man made
versions of pyrethrins
Pyrethrum is composed of 6 esters
collectively called as pyrethrins
It is only one active compound
Pyrethrins are naturally broken
down by UV rays and PH variations
and therefore have shorter
environmental persistance
These are synthesized to
overcome that problem
Flushing effect is present:
Excitation of the insect, erratic and
increased movement of the insects
No flushing effect
18. BOTANICAL BIOPESTICIDES
8. Limonene and linanool
•These are citrus peel extracts which cause insect paralysis.
•They evaporate quickly in environment and are used to control
aphids, mites and fleas
