When I was young, I regularly came across news articles that advocated the use of bio pesticides and avoid the usage of chemical pesticides. However, I didn’t bother much about it much until I read a news article about a chemical pesticide used for cashew-nut cultivation to control insects. Endosulfan is commonly used by farmers in Kerala and it was also introduced in Tamilnadu. Since cashew nut is grown in a large area, the chemical is typically aerially sprayed, which affected the soil, water and humans living there. This pesticide has led to the birth of genetically deformed children and caused permanent disabilities among people.
My district in Tamilnadu is famous for cashews, so I checked with my relatives in my village about the pesticide they use at our field. I was shocked to find that they were also using the same Endosulfan! Then I realized that to make them avoid using chemical pesticides, we should find new alternatives that eliminate pests and enable farmers to grow crops.
Bio pesticides – A better alternative
“Biological pesticides”, or ‘Biopesticides’ as the name suggests, are naturally occurring substances that biologically control harmful pests, especially among field crops. These are naturally produced bio-chemical materials basically non-toxic to the environment that can be employed in pest control. Bio-pesticides could mean living organisms (bacteria, virus, and algae), their products (bio-chemicals produced by them) and also plant byproducts. Biopesticides offer an ecologically effective solution to the harmful effects of synthetic pesticides.
Advantages of bio pesticides are eco friendly, affect only target pest groups, biodegradable and minimal quantity is enough. Unlike biopesticides, chemical pesticides are not target specific which not only kill harmful pests, but also end up destroying plant friendly organisms such as earth worms, nitrogen fixing bacteria and algae that help plants to suck nutrients from soil, water and air. Although they help the farmers with increased output they also result in polluting the environment. However, biopesticides are harmless, target specific and biodegradable.
Types of Biopesticides
Biopesticides are an important ingredient of Integrated Pest Management (IPM) packages due to their capability in maintaining the natural diversity without the use of any artificial or synthetic residues. The origin of Biopesticides can be microbial (bacteria, fungi or virus), herbal (plant extracts) or genetically modified plants (GM). Beauveria spp., Trichoderma spp., and Bacillus spp., are some of the microbial biopesticides. Products made out of garlic and neem is used extensively as herbal biopesticides. Traditionally, GM varieties resistant to particular pests are used in crops (e.g. Bt Brinjal) and cotton (Bt Cotton). There are mainly three categories in Biopesticides:
- Microbial pesticides: These pesticides originate from micro-organisms such as bacteria, fungi or other protozoan groups. These are mostly target-specific organisms that are aimed at killing one or a group of pests.
- Biochemical pesticides: These herbal-based substances are naturally produced by a plant or an organism. They are non-toxic and biodegradable. They help the plant in counter-attacking its pests or producing chemicals that would prevent pest attack on the plant. Examples are fatty acids, pheromones.
- Plant incorporated protectants: These are genetically modified materials produced by scientists by modifying a protein and introduced into the plant so that it produces its own pesticide.
Biopesticides Technology
The Biopesticide segment occupies a small portion of the large pesticide market in India. In 2005, it accounted for just 2.89%, which was expected to increase to 5%. Until 2011, there were 12 different types of biopesticides registered in India. Last decade, has witnessed a rapid growth in this segment, especially on standardization of production techniques of Trichoderma, Gliocladium, Paecilomyces, Pseudomonas, Trichogramma, NPV and Bacillus to use them against many insect pests and diseases. Today, these biological control agents have been successfully employed in India.
Trichogramma, which is a stingless wasp that feeds on the eggs of sugarcane borers, has been used against borers in the states of Tamil Nadu, Rajasthan, UP, Bihar and Haryana. Similarly Trichogramma, Bracon, Chelonus and Chrysopaspp are being used for the control of cotton bollworms. Trichogramma has also been used against rice stem borer and leaf folder. The sugarcane scale insect has been controlled with the help of predatory Coccinellid beetles in UP, West Bengal, Gujarat and Karnataka. Here is a compilation of different technologies used in producing bio pesticides with few examples:
| Bio Agent | Manufacturing process | Utilization |
|---|---|---|
| Trichogramma spp. (egg parasite) | Mass multiplied by using stored grain pest as a host. Production involves the multiplication of host insect on sorghum grains, which is allowed to be parasitized by Trichogramma. Then eggs are clued in cards as ‘tricho cards’ | Used for control of sugarcane early shoot borer, cotton bollworms, sorghum stem borer |
| Crysoperla carnea (Chrysopid predetor) | Mass multiplied in the laboratory on the eggs of stored grain pest | To control larval pest in pulses, vegetables and fruits |
| Cryptolaemus montrouzieri(Ladybird beetle) | Mass multiplied on mealy bugs with the help of pumpkin as under laboratory conditions | To control mealy bugs especially on fruits |
| NP Virus of Helocoverpa armigera & Spodoptera litura | Production starts with rising of pod borer and tobacco caterpillar larvae (host culture) on semi-synthetic diet. NP Virus is smeared on cultured larvae. Then the diseased larvae are collected to obtain virus suspension by blending, filtration and centrifuging | Used against bollworms in cotton and pod borers |
| Trichoderma Fungal spp | Multiplied in labs and formulated in a powder form with the help of carrier material (talc powder) | To control root rot and wilt diseases especially on pulses |
| Pheromone lures for Helicoverpa armigera & Spodoptera litura | Sex pheromones are filled into plastic traps at required concentration with the help of micro-pipettes and placed into rubber septa. The septa is fixed to the trap | To trap productive male of gram pod borer and tobacco caterpillar |
Biopesticides Neem
Neem oil is most commonly used as biopesticide by most of the villagers. With growing awareness about benefits of neem as a natural pesticide, the estimated INR100 crore neem-based pesticide markets in the country is growing by 7-9% annually, says a report by Export Import Bank of India. The report also verifies that the U.S. was the largest importer of neem extracts from India with $2.62 million imports in FY2011-12. Institutes like Centre for Indian Knowledge Systems, National Innovation Foundation and Neem Foundation are involved in R&D for biopesticides in India.
Bio pesticide Research in India
Research work in biopesticides is mainly funded by the Government Department of Bio Technology. The Indian Council of Agricultural Research, Bangalore Indian Institute of Horticulture Research, Hesaragatta, Bangalore Central Integrated Pest Management Centre (CIPMC), TNAU Agritech, Bangalore Central Institute for Cotton Research (CICR), Nagpur Bio pesticides companies in India:
Biopesticides registered in India:
1. Bacillus thuringiensis var. israelensis 2. Bacillus thuringiensis var. kurstaki 3. Bacillus thuringiensis var. galleriae 4. Bacillus sphaericus 5. Trichoderma viride 6. Trichoderma harzianum 7. Pseudomonas fluoresens 
I have presented all the information available about biopesticides, their types, comparison with synthetic pesticides, their advantages and the latest research work, technology involved, etc. Now, it is up to the farming community to get benefitted by the usage of biopesticides, saving the soil properties and also considering the effects on future generations.
