Sex pheromone trap or pheromone trap
Organic Control of Pests and Diseases
Monitoring of pest population is a pre-requisite to efficient pest management strategy. Several methods
are used for determining the pest population.
Pheromone trap is one such tool, which is used for monitoring of pests.
Sex pheromones are bio-chemicals released usually by female insects as a means of chemical
communication to attract males for mating. They are highly specific and are perceived by the males of the
same species only. The synthetic pheromones are now is use for luring a variety of lepidopterous pests in
small entrapments popularly called pheromone traps. These traps are effectively used in cotton, rice,
vegetable and many other crops. Two traps per acre are often sufficient for monitoring the pest population.
Pheromones are also exploited for mass trapping of certain pests particularly yellow stem borer in rice,
Usually ten traps per acre are used to mass trap the moths to reduce their population. Of late,
pheromones are also used for disruption of mating cycle. Small bits of rope impregnated with
pheromones are strewn for dispensing this chemical in the field. The crop environment pervaded by
pheromone confuse the females to the extent that their mating get disrupted in spite of the fact that males
are there in the field. The unmated females are rendered incapable of laying the eggs. Pheromones can
be effectively used in organic farming.
Biocontrol agents
Ecofriendly organic farming technologies for plant protection have been gaining importance in recent
years. Commercial production of Biopesticides containing different bacteria, fungi and viruses has been
undertaken to control certain insects. Spraying of Bacillus thuringiensis, a bacterium, has successfully
killed several lepidopteran insects. Another strategy could be to use beneficial insects like ladybugs, which
feed on aphids to control harmful pests. Some of the plant diseases that cab be controlled by antagonistic
fungi and bacterial are as follows:
Aspergillus niger AN 27 was found effective against several diseases caused by soil borne pathogens, viz.
wilt (Fusarium oxysporum, F. Solani), charcoal rot (Macrophomina phaseolina), damping off (Pythium
aphanidermatum). Sheath blight (Rhizoctonia Solani) and stalk rot (Sclerotinia sclerotiorum) by a single
application under different agro-climates in cereals, millets, pulses, oilseeds, fruits, tuber vegetables, and
ornamental, fodder and fiber crops. The commercial preparation is known by the name, Kalisena.
Rice seeds treated with Pseudomonas aeruginosa and P. putida reduced sheath blight infection
(Rhizoctonia Solani) in rice by 65-72 per cent in comparison to untreated check. P. fluorescens was also
found effective against banded leaf and sheath blight fungus (R. Solani f. sp. Sasakii).
Trichoderma harzianum as fungal antagonist proved effective against Macrophomina phaseolina
(charcoal rot) in several plant species.
Application of rooting media, peat moss + wheat bran + perlite (2:1:2) mixed with Trichoderma harzianum
(TH3) 14-16 days before transplanting of carnation was found effective and reduced 76-78% of wilt
incidence caused by F. oxysporum F. sp. dianthi and increased the yield. It was followed by cocopeat +
wheat bran + perlite (2:1:2).
T. harzianum isolate TH3, was found most effective against Colletotrichum capsic causing fruit rot and die
back of chilli in vitro followed by isolates TH4 and TH 1. Two sprays of conidial suspension of T. harzianum
(TH3), one before 48 h of inoculation and second after 15 days of inoculation, were found effective in which
lowest fruit rot intensity (44.5%) with 32.9% disease reduction was recorded. It was followed by sprays of
T. viride – 2, and Aspergillus niger AN-27.
Five pseudomonads were found effective against Xanthomonas campestris pv malvacearum (X cm)
causing bacterial blight and Sclerotium rolfsii and Rhizoctonia Solani causing damping off in cotton. Seed
bacterisation with Pseudomonas fluorescens (PR 8) reduced damping off disease incidence caused by
R. Solani and S. rolfisii by 84 and 76% respectively. Seed bacterisation with the same isolate of P,
fluorescens reduced the cotyledonary infection of X cm.
Trichoderma harzianum and Pseudomonas fluorescens effectively suppressed mycelial growth, sclerotial
production and germination of Rhizoctonia Solani causing root rot of wheat.
Chaetomium globosum Kunze Fr. has been identified as a potential biocontrol agent of spot blotch of
wheat caused by Drechslera sorokiniana. It is also antagonistic to Ascochyta rabiei and Fusarium
oxysporium ciceri causing ascochyta blight and wilt of chickpea, respectively. The mechanism of action is
through antibiosis. The antagonist is sprayed on the crop @ 106 ascospoers/ml for the control of spot
blotch of wheat and ascochyta blight of chickpea. For the control of chickpea wilt, the bioformulation is
amended in the soil @ 8 g/1 meter row in the field before sowing.
Many botanicals have the potential to control pests and diseases of plant. Extracts of neem, custard apple
and callophyllum (undai) seed can control a wide range of insects, bacterial and fungi (tables-1).
Harmful insect-pest can also be controlled by releasing appropriate biocontrol agents in the field (table-3).
Table I. Pests controlled by neem seed kernel extract
Insect species
Desert locust, Schistocerca gregaria
White flies, Bermisia tabaci
Mustard aphid, Lipaphis erysmi
Cabbage aphid, Brevicoryne brassicae
Leaf miners, Liriomyza trifolli and L. sativae
Pod fly, Melanagromyza obtuse
Citrus leaf miner, Phyllonistis citrella
Hairy caterpillar, Amsacta moorei
Diamondback moth, Plutella xylostella
Tobacco caterpillar, Spodoptera litura
Swallowtail butterfly, Papilio demoleus
American bollworm, Helicoverpa armigera
Stem borer, Chilo partellus in Whorl
Kernel powder g/I
5
50
50
20
15
80
100
10
50
20
30
50
0.5 g/plant
Kernel powder kg/ 600 I water / h
3
30
30
12
9
48
60
6
30
12
18
30
25
Table 2. Pests controlled by neem oil suspension in water.
I oil/600I Water / h
30
9
9
6
9
60
15
12
6
mI/I
50
15
15
10
15
100
30
20
10
Insect species
Leaf hopper – Nephotettix virescens
White fly – Bemisia tabaci
Green aphid- Myzuz persicae
California red scale – Aonidiella aurantii and yellow scale – A. citrina
Asiatic citrus psyllid – Diaphorina citri
Brown plant hopper – Nilaparvata lugens
Gall midge – Orseolia oryzae
Whorl maggot – Hydrellia sp.
Potato tuber moth – Phthorimaea operculella
Table 3. Biocontrol agents for used in organic farming.
Biocontrol agents
Egg parasitoids
Trichogramma chilonis
Trichogramma exiguum
Trichogramma brasiliensis
Trichogramma japonicum
Trichogrammatoidea bactrae
Telenomus remus
Egg-larval parasitoids
Chelonus blackburni
Copidosoma koehleri
Larval Parasitoids
Apanteles angaleti
Cotesia plutellae
Predators
Cryptolaemus
montrouzieri
Scymnus coccivora
Nephus regularis
Chrysoperia carnea
Cheilomenes sexmaculata
Brumoides suturalis
Pathogens
Bacillus thuringiensis
Ha NPV
S/NPV
Target pest
Chilo partellus
Sesamia inferens
Chilo sacchariphagus
Indicus
Chilo auricillus
Helicoverpa armigera
Chilo sp.
Helicoverpa armigera
Helicoverpa armigera
Pectinophora gossypiella
Tryporyza incertulus
Tryporyza nivella
Plutella xylostella
Spodoptera litura
Spodoptera exigua
Earias sp.
Pectinophora gossypiella
Phthorimoea operculella
Phthorimoea operculella
Pectinophora gossypiella
Plutella xylostella
Maconellicoccus
hirsutus
Ferrisia virgata
Planococcus sp.
Soft bodied insects such as aphids
Aphis craccivora,
Aphis gossypii
Mealy bugs, Aphis craccivora, Aphis sp.
Lepidopterous larvae
H. armigera
Spodoptera Litura
Crops
Sorghum and maize
Sugarcane
Tomato, cotton, vegetables
& pulses
Sorghum, maize and
sugarcane
Cotton and vegetables
Cotton and tomato
Rice
Sugarcane
Cabbage, cauliflower
Vegetable & Cotton
Vegetable and chickpea
Cotton and okra
Potato
Potato
Cotton
Cabbage, cauliflower
Guava, Sapota,
Crotons & and other
ornamentals
Guava, Sapota, crotons and
other ornamentals
Guava, Sapota, crotons and
other ornamentals
Cotton
Bean and cotton
Fruits and cotton
All crops
Cotton, chickpea and
Pigeonpea
Vegetable & cotton
It has been observed that some plants when planted together help each other to grow and also help to
keep pests at a minimum. Such plants are called companion plants. Some tested companion plants are
carrots and tomatoes; cauliflower and potatoes; and peas and cucumber.
Cultural practices
The cultural practices also help in controlling weeds and plant diseases. For example, in maize, the
following practices have helped to control several bacterial and fungal diseases:
Field sanitation by removing the previous crop straw, proper drainage to avoid water logging, and
regulation of plant density (55 thousand plant/ha) were found effective for the management of Pythium
stalk rot of maize.
Stipping off lower 2-3 leaves along with sheath when the crop is 30-35 days old proved very effective
for the management of banded and leaf and sheath blight disease.
Removal of ‘Kans’ grass from adjoining area of the main crop field helped in the reduction of downy
mildew incidence in maize.
Karnal bunt management
Polythene mulching significantly reduced Karnal bunt by 63-75% over that of the check. Live mulching by
chickpea, which did not do soil solarization like plastic mulching but restricted the liberation of Karnal bunt
sporidia from soil, resulted in reducing the disease level by 40-57 per cent.