Presentation Recent Advances in Bio pesticides - PowerPoint Presentation

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Presentation Recent Advances in Bio pesticides

GHULAM MURTAZA

Department of Soil And Environmental Sciences, UCA, University of Sargodha

PesticideA pesticide is any substance or mixture of substances intended for preventing , destroying , repelling , or mitigating any pest.Pest include insects, plant pathogens, weeds, birds, and microbes etc.

Classification on the basis of Targeted OrganismPesticides

Algicides

Virucides

Rodenticide

Fungicides

Herbicides

insecticide

Avicides

Bactericide

miticides

nematicide

Types Of Pesticides

Chemical Pesticides1. Organochlorides, which

have a high persistence in the environment of up to about 15 years (DDT, dieldrin

and aldrin

2

.

Organophosphates

,

which have an intermediate persistence of several months (parathion, carbaryl and malathion)

3

. Carbamates

, which have a low persistence of around two weeks (Tenik, Zectran and Zineb)

4

. Synthetic pyrethroids, which are nonpersistent, contact and residual acting insecticides (cypermethrin, permethrin),

suitable for a wide range of crops and target insect

Prominent Families of HerbicidesPhenoxy and Benzoic Acid Herbicides e.g. 2,4-D Triazines e.g. ( Atrazine) interfere with photosynthesisUreas e.g Diuron

Chloroacetanilides e.g alachor

Biopesticides

Biopesticides are certain type of pesticides derived from such natural materials as plants, animal and microbes like bacteria, fungi etc.

Types

Microbial Biopesticides

Biochemical

Biopesticides

Plant Biopesticides

Microbial Pesticides

Microbial pesticides are composed of microscopic living organisms (viruses, bacteria, fungi, protozoa, or nematodes) or toxin produced by these organisms

Applied as conventional insecticidal sprays, dusts, or granules.

Their greatest strength is their specificity as most are essentially nontoxic and non pathogenic to animals and humans.

Microbial pesticides includes insecticides, fungicides, herbicides and growth regulators of microbial origin.

Some of the important microbial pesticidesa.

Bacillus thuringiensis

Discovered in Japan in early 20

th

century and first become a commercial product in France in 1938.

Control lepidopterous pests like

American bollworm in cotton

and stem borers in rice.

Fig:

Bacillus thuringiensis

When ingested by pest larvae, Bt releases toxins which damage the mid gut of the pest, eventually killing it.

Main sources for the production of Bt preparations are the strains of the subspecies

kurstaki, galeriae and dendrolimus

e. Metarizium anisopliae

It infects spittlegbugs, rhinoceros beetles.

f.

Beauveria bassiana

C

ontrols Colorado potato beetle.

g.

Verticillum lecanii

:

C

ontrols aphids and whiteflies

.

h.

Nomuraea riley

:

Controls soybean caterpillars.

i.

Baculoviruses

(Bvs)

Control lepidopterous and hymenopterous pests.

Rod shaped, circular double stranded super coiled DNA.

Fig: Metarhizium anisopliae

Fig: Beauveria

2. Plant Biopesticides

Pesticides derived from plants

Generally act in one of two ways

Contact poison

Stomach poison

About 250000 plant species evaluated

2121 useful in pest management

1005 exhibited insecticidal activity

384antifeedants

297 repellents

27 attractants

31 growth inhibiting properties

Plant-incorporated- protectants (PIPs)Pesticidal substances that plant produce from the genetic material that has been added to the plant.

As the pest feed on such plants they will eventually die

.

Botanical pesticides:

These are naturally occurring plant material that may be crude preparation of the plant parts ground to produce a dust or powder that can be used in full strength or dilute form in a carrier such as clay, talc or diatomaceous earth.

“Azadirachtin” effects the reproductive and digestive process of pest.

Several plant based insecticides as nicotinoids, natural pyrethroids, rotenoids, neem products etc are used.

4.Biochemical pesticidesThey are naturally occurring substance to control pest by non-toxic mechanisms. Biochemical pesticides include substances as insect sex pheromones, that interfere with mating that attract insect pest

to traps.

The synthetic attractants-

are used in one of four ways:

As a lure in traps used to monitor pest populations;

As a lure in traps designed to “trap out” a pest population;

As a broadcast signal intended to disrupt insect mating

As an attractant in a bait containing an insecticide

Fig: weevil pheromone trap

THE ADVANTAGES OF USING BIOPESTICIDESBiopesticides are usually inherently less toxic than conventional pesticides.Biopesticides generally affect only the target pest and closely related organisms,

Biopesticides often decompose quickly, avoiding the pollution problems caused by conventional pesticides.

Biopesticides can greatly decrease the use of conventional pesticides, while crop yields remain high.

Cheap, renewable can be handled safely.

Difficult for insects to develop resistance to these pesticides.

DISADVANTAGES OF USING BIOPESTICIDESSlow effectLack persistence and wide spectrum activity

Rapidly degraded by UV lights so residual action is slow.

Seasonal availability of plants products indicates the needs for storage.

They are not available easily

Poor water solubility and generally not systemic in nature

All products applied followed by growers have not been scientifically verified.  

Fate of PesticidesOnce a pesticide is applied, several things may happen. It may be taken up by plants and/or ingested by animals, insects, worms, or microorganisms in the soil

It may move downward in the soil and adhere to soil particles, or it may dissolve

It may volatilize

It may be broken down into less toxic compounds

It may be leached or moved out of the plants root zone by rain or irrigation water or

It may be carried away by runoff water or erosion

Factors Affecting Fate Of Pesticides There are four major factors which affect the fate of pesticides. They are as follows:1. Properties of the pesticide2. Properties of the soil

3. Conditions of the site

4. Management practices

ConclusionBiopesticides are typically microbial biological pest control that are applied in a manner similar to chemical pesticides. Available in different formulations

Also used to control soil borne and seed borne fungal pathogens

Disadvantages of them are, high specificity, slow speed of action and their requirement of suitable condition for their survival.

Even though, biopesticides are best for controlling the pests of agriculture then the chemicals

Therefore there should be more works on production on biopesticides and encourage people to use biopesticides to control the pests.

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