3. INTRoDUCTIoN
BIOCONTROL- use of natural or modified organisms, genes, or gene products” to
reduce the effects of pests and diseases.
The production of food grain should increase to 250 million tones by the year
2020 in order to meet the needs of the growing population.
The environmental pollution caused by excessive use and misuse of
agrochemicals, has led to considerable changes in people’s attitudes towards the
use of pesticides in agriculture.
(1)Biological control is less costly and cheaper than any other methods.
(2) Biocontrol agents give protection to the crop throughout the crop period.
(3) They do not cause toxicity to the plants.
(4) Application of biocontrol agents is safer to the environment and to the person
who applies them.
(5) They multiply easily in the soil and leave no residual problem.
(6) It increases the crop yield .
(7) Biocontrol agents are very easy to handle and apply to the target.
(8) Biocontrol agent can be combined with bio-fertilizers.
(9) They are easy to manufacture.
4. Biological control practices involve 3 major techniques ,i.e. Introduction ,
augmentation and Conservation.
1.Introduction or classical biological control: It is deliberate introduction and
establishment of natural enemies to a new locality where they did not occur or
originate naturally.
2.Augmentation: It is the mass rearing and releasing of natural enemies to
supplement the numbers of naturally occurring natural enemies .
It is 2 types:
A. Inoculative release: In this case control is expected from progeny and
subsequent generation . It is done infrequently once in a year .
B. Inundative release: In this case control is expected directly from released
individuals. Here NE are mass reared and released frequently.
3.conservation: It is the action taken to preserve and increase natural enemies by
environmental manipulation.
The microbial biocontrol agents are applied in field generally by 3 ways;
i. Seed treatment
ii. Soil application
iii. Foliar application
5. TECHNIQUE FOR APPLICATION OF beetles.
These beetle are applied into field by general biocontrol technique:
Augmentation technique: The beetles are mass reared and released periodically
in the field against the target pest.
•Mass Production
To release the predator in large numbers in the field, mass culture of Cryptolaemus
is a pre-requisite. Cryptolaemus is easily cultured on a large scale on the mealybugs
particularly pink hibiscus mealybug and citrus mealybug. In the culture room, it is
ideal to maintain 25 to 30°C.
•Stage to be released
Adults and larvae can be released in the field for the suppression of pests.
•Time of release
Usually the releases are made between 8.00 AM and 10.00 AM and 3 PM and 5 PM.
•Dose of release
A release rate of 5000 beetles/ha is recommended to control mealy bugs by
Creptolaemus montrouzieri.
•Likewise beetles are released against weeds and insects.
7. Trichogramma Release Techniques
Correct timing of Trichogramma release requires good coordination between the
rearing facility and field staff.
There can be 2 methods of field applications :
1. RELEASE ON CARDS:
The Trichogramma are shipped (as pupae) inside of grain moth eggs ready to emerge
as adults. They can be loose or glued to perforated cards.
Moth eggs glued on cards with 100,000 Trichogramma per card (up to 120,000) .
8. The card can be broken into 30 squares (hangable units)with 4,000 parasites per
square inch that permits even distribution in fields and orchards.
The cards can be stapled under leaves.
The wasps emerge in two to five days, depending on temperature, which should
ideally be 80º to 90ºF.
Emergence can be delayed by holding parasitized moth eggs at cooler temperatures
(not less than 40 ºF) and emerging wasps are usually seen in the morning.
To maximize pest fighting time, do not delay release after adult wasps emerge.
Keep Trichogramma cards in the shade, out of the hot sun and application rate
protocols for Trichogramma spp, can be changed, according to the height of the crop to
determine the proper species to choose .
9. Advantages are superior percentage emergence and survival in the field.
It can be done by several methods:
A. Glass Jar Incubation Containers:
•Any size jar can work from pint to gallon according to convenience and size of release.
•Use a tight-fitting lid.
•Shredded paper or thin strips of cloth in the container makes it easier to lift the live
Trichogramma adults to the tree.
•If growers do not use shredded paper and they do not fly out of the jar easily, wrap the
jar in a jar cloth or bag so they can be attracted to the mouth of the jar.
• Benefit of using a jar is ability to see the wasps & the proportion remains to be released
.
2.RELEASE AS ADULTS :
10. B. Paper Bag Incubation Containers:
•Any size paper bag can work from a lunch bag to a grocery bag, but there should
not have holes in it.
•Again, put some material like shredded paper, short pieces of string or other
material in the bag.
•If the bag and other material are white or light coloured it is easier to see the
moving specks that are the wasps.
•The benefit of using a paper bag is ease of handling and Trichogramma that is
not walking on the paper shreds can be more likely to leave the bag than a clear jar
.
12. PRECAUTIONS:
Users are advised to handle all microbial insecticides cautiously. Bacterial spores,
as well as other microbes, become “foreign proteins” if they are inhaled or rubbed
into the skin and can cause allergic reactions.
There are many microbial agent used as biocontrol agent.
•Methods used are : soil application , seed pelleting , seed treatment , foliar
application etc.
•The microbial insecticides are: NPV, Bt, Fungi, EPN etc.
•Biocontrol agent is available as suspension or dry powder.
•Treating the seed material with bio control agent is most economical against
seed borne or soil borne pathogen.
•sticker are also used for increasing efficiency such as :Carboxymethyl
cellulose(1%) , Polysulf(0.8%) , Polymethyl alcohol(20%) for treating seed.
•Dipping of roots in preparation of Pseudomonas fluorescens reduces the
disease by 60-80%.
13. 1.TECHNIQUEFORAPPLICATIONOF Bt ANDITS
FORMULATIONS
•Bt and its toxins can be formulated into liquid
concentrates, wettable powders, and ready -to-use dusts
and granules or expressed in transgenic plants.
•Bt formulations may be applied to foliage, soil, water
environment or food storage facilities.
•The best-known and most widely used Bt insecticides
are formulated from Bacillus thuringiensis var. kurstaki
isolates that are pathogenic and toxic only to larvae of
the butterflies and moths. Many such Bt products have
been registered with the United States Environmental
Protection Agency.
•The most common trade names for these commercial
products include Dipel®, Thuricide®, Worm Attack®,
Caterpillar Killer®, and SOK-Bt®.
•Each Bt insecticide shows high degree of specificity.
Susceptible insects must consume Bt to be poisoned, so
treatments must be directed to the plant parts or other
material that the target pest will eat.
14. •Where Bt is applied to plant surfaces or other sites exposed to sunlight, it is
deactivated rapidly by direct ultraviolet radiation.
•To maximize the effectiveness of Bt treatments, sprays should thoroughly cover
all plant surfaces, including the undersides of leaves.
•Treating in the late afternoon or evening can be helpful because the insecticide
remains effective on foliage overnight before being inactivated by exposure to
intense sunlight the following day.
•Treating on cloudy (but not rainy) days provides a similar result.
•Production processes that encapsulate Bt spores or toxins in a granular matrix
(such as starch) or within killed cells of other bacteria also provide protection
from ultraviolet radiation.
15. APPLICATIONTECHNIQUEFOR ENTOMOPATHOGENICFUNGI
•The most common method used has
been the immersion of any insect stage
(larva, pupa or adult) in a conidia
solution .
•Application of conidia to the soil have
been suggested as a method to use these
entomopathogenic fungi for fruit fly
control .
•Howse and Underwood (2000)
proposed the use of electrostatic charged
powders to spread a killing agent within
a pest population.
16. Dry root rot of mung bean caused by Macrophomina phaseolina was
reduced by seed pelleting of Trichoderma viride isolates when talc was
used as carrier. Among the isolates, T viride-III supported higher plant growth,
better native Rhizobium nodulation and grain yield.
SEED PELLETING:
•For this eight-day old culture of T viride
isolates and T harzianum maintained in 250 ml
Erlenmeyer flask containing 70 ml of yeast
molasses broth were mixed including the
mycelial mat and metabolites using a mixie.
•Further, it was mixed with taIc powder @ 1:2
(v/w) and shade dried for 2 days.
•Carboxymethyl cellulose (10g) was added as
sticky material for 1 kg of talc powder.
•The talc based Trichoderma formulation was
used for treating the seeds at 4g/kg of seeds.
•This talc based formulation contains 1 x 107
CFU/g of talc on serial dilution (Ramakrishnan
et al., 1994).
•For comparison, carbendazim was used for
seed treatment at 2g/kg of seed.
17.
18. •The EPN can be applied in the field by mixing with
irrigation water through irrigation channel.
Technique for application of EPN
19. REFFERANCE
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(Hymenoptera: Trichogrammatidae) strikes for caterpillar control . International
Journal of Entomology Research. (1): 31-36
Toledo.J, Liedo. P, Flores.S, Campos.S.E, Villaseñor. A and Montoya,P. (2006).use of
Beauveria bassiana and Metarhizium anisopliae for Fruit Fly control: A novel
Approach. Fruit Flies of Economic Importance: From Basic to Applied Knowledge
Proceedings of the 7th International Symposium on Fruit Flies of Economic
Importance .10-15 September 2006, Salvador, Brazil.pp. 127-132
Raguchander .T., Rajappan. K. and Samiappan R. (1997). Evaluating methods of
application of biocontrol agent in the control of mungbean root rot. Indian
Phytopath. 50 (2) : 229-234 .
Ramakrishnan, G., Jeyarajan, R. and Dinakaran, D. (1994). Talc based formulation
of Trichoderma viride for biocontrol of Macrophomina phaseolina. J. Biological
Control 8: 41-44.
Howse, P. E., and K. L. Underwood. 2000. Environmentally safe pest control using
novel bioelectrastatic techniques: Initial results and prospects for area-wide
usage, 295-299. In: K. H. Tan [ed.]. Area-wide control of fruit flies and other
insect pests. Penerbit University Sains Malaysia. Penang, Malaysia.