Biopesticides

Introduction of biopesticides, advantages & disadvantages, types, applications and examples of biopesticides

1. Presented by: Mahewashsana A. Pathan

2. Introduction Biopesticides are certain types of pesticides derived from natural materials as animals, plants, bacteria, and certain minerals. The most commonly used biopesticides are living organisms, which are pathogenic for the pest of interest. These include biofungicides ( Trichoderma ), bioherbicides ( Phytopthora ) and bioinsecticides ( Bacillus thuringiensis ). There are few plant products also which can now be used as a major biopesticide source. Biopesticides are mass-produced, biologically based agents used for the control of plant pests. They can be living organisms (nematodes or micro-organisms) or naturally occurring substances, such as plant extracts or insect pheromones.

3. After successful implementation of 'green revolution’ India became self sufficient in food production, production of food grains increased four fold, soil & environment health have been affected adversely. According to one survey, application of 250 times more chemical fertilizers & 400 times pesticides also happened. As harmful effects of chemical fertilizers & pesticides are evident, there is a growing need for Research and it development of biological alternative such as biopesticides and bio fertilizers. Indian government, ministry of agriculture has taken initiative under Dr. M. S. swaminathan from 2004. in 2006 use of biopesticides was only about 12 to 15%. detail framework has been prepared for the application of biotechnology in agriculture for security of food, health, environment and national as well as international trade. large-scale field testing of released transgenic variety and seeds is under consideration as per agronomic requirements.

4. Advantages of biopesticides: These are less harmful to crop plant & human. They are highly specific in action. These are very effective in small quantities also. These are environmental friendly as they decompose quickly. They are only eco-safe alternative & do not have problematic residues. Development of resistance is less common in case of biopesticides.

5. disadvantages of biopesticides: The  disadvantages of biopesticides  include a slower rate of kill compared with conventional chemical pesticides, shorter persistence in the environment and susceptibility to unfavourable environmental conditions. Unintended consequences : Studies have found broad spectrum biopesticides have lethal and nonlethal risks for non-target native pollinators such as  Melipona quadrifasciata  in Brazil. Living organisms evolve and increase their resistance to biological, chemical, physical or any other form of control. If the target population is not exterminated or rendered incapable of reproduction, the surviving population can acquire a tolerance of whatever pressures are brought to bear, resulting in an  evolutionary arms race . Often variable efficacy due to the influences of various biotic and abiotic factors.

6. Types: Biopesticides can be classified into these classes- Microbial  pesticides which consist of bacteria,  entomopathogenic fungi  or viruses (and sometimes includes the metabolites that bacteria or fungi produce).  Entomopathogenic nematodes  are also often classed as microbial pesticides, even though they are multi-cellular. Bio-derived chemicals . Four groups are in commercial use:  pyrethrum ,  rotenone ,  neem oil , and various  essential oils  are naturally occurring substances that control (or monitor in the case of  pheromones ) pests and microbial diseases. Plant-incorporated protectants (PIPs) have genetic material from other species incorporated into their genetic material ( i.e.   GM crops ). Their use is controversial, especially in many European countries. RNAi pesticides , some of which are topical and some of which are absorbed by the crop.

7. Applications of biopesticides Biopesticides are  biological or biologically-derived  agents, that are usually applied in a manner similar to chemical pesticides, but achieve pest management in an  environmentally friendly  way. With all pest management products, but especially microbial agents, effective control requires appropriate  formulation  and  application . Biopesticides for use against crop diseases have already established themselves on a variety of crops. For example, biopesticides already play an important role in controlling downy mildew diseases. Their benefits include: a 0-Day Pre-Harvest Interval, the ability to use under moderate to severe disease pressure, and the ability to use as a tank mix or in a rotational program with other registered fungicides. Because some market studies estimate that as much as 20% of global fungicide sales are directed at  downy mildew  diseases, the integration of bio-fungicides into grape production has substantial benefits in terms of extending the useful life of other fungicides, especially those in the reduced-risk category. A major growth area for biopesticides is in the area of  seed treatments  and  soil amendments .  Fungicidal  and bio-fungicidal seed treatments are used to control soil born fungal pathogens that cause seed rots, damping-off,  root rot  and seedling blights. They can also be used to control internal seed–borne fungal pathogens as well as fungal pathogens that are on the surface of the seed. Many bio-fungicidal products also show capacities to stimulate plant host defence and other physiological processes that can make treated crops more resistant to a variety of  biotic  and  abiotic  stresses.

8. Examples of biopesticides & bioinsecticides : Fungi of Trichoderma app. have approved useful for many pathogens, including Rhizoctonia saloni , Sclerotium rolfsil , Sclerotinia sclerotiorum & Pythium aphanidermatum . Trichoderma harzianum as nematode inhibitor, fungicide & plant growth promoter. An alcoholic extract of plant Albizzia lebbeck along with Bacillus thuriengiensis delta endotoxin acetone powder is used to kill lepidoptera insects. plants containing essential oils like Artemisia anuua , Anethum sowa , Curcuma longa , Lippia alba have potential for fumigant use Compounds like cineole, geraniol , piperidine possess repellant properties towards cockroaches. Limonene is toxic to adult beanweevils . Some strains of B. subtilis inhibit the growth of several fungal pathogens. The seed oil from custard apple is used with neem oil for control of rice green leaf hopper pest Nephotettrix virescens . Shell of cashew, Anacardium occidentals & seed oil of Pongamia pinnata are used as insecticide.

9. SR no. Control of pest Biopesticides used 1 Diamondback moths Bacillus thuriengiensis 2 Mango hoppers, mealy bugs, coffee pod borers Beavueria 3 Helicoverpa on cotton, pigeon pea on tomato Bacillus thuriengiensis 4 White fly on cotton Neem 5 Rota & wilts in various crops Trichoderma based products 6 Sugarcane borers Trichoderma

10. Sr no. Name of biopesticides Average production (Approx) 1 Neem 300 PPM Over 1000000 L 2 Neem 1500 PPM Over 250000 L 3 Bacillus thuriengiensis Over 50000 kg 4 Nuclear polyhedrosis virus (NPV) Over 500000 L.E 5 Beauveria --- 6 Pheromone traps Over 500000 7 Lures Over 2 million 8 Crysoperia & other biocontrol insects ----