1. Pesticide Use in Rice IPM
Introduction
Pesticides have of course played a commendable role in increasing our food production and protecting us against disease vectors. However, sole reliance on pesticides has created several problems such as development of resistant pests, pest outbreaks, mortality of useful organisms, adverse effect on human health and environmental degradation. Adverse effects of pesticides prompted scientists to look for environment friendly methods of pest control and consequently IPM was conceptualized.
Pesticide spraying

2. In IPM, different methods of pest control such as resistant varieties, cultural methods, physical methods, natural enemies and pesticides are integrated to suppress pest population without jeopardizing other components of the environment. Pesticides have definite role to play in IPM but their use has to be need-based. Pesticides are important weapons with man against obnoxious pests and their useful life needs to be prolonged through their judicious application.
IPM Concept

3. Judicious pesticide use
If pesticides have to play a significant role in pest management, they need to be used in accordance with IPM principles. These have to be used judiciously as last resort and not as first option. Need for pesticide use should be determined through continuous monitoring of pests on crop. Pesticides should only be used if pest incidence tends to approach economic threshold level. Properly timed one pesticide application may very well substitute for 3-4 ill timed treatments.
Pest monitoring

4. Selective use of pesticides
In case pesticide application is unavoidable, preference should be given selective pesticides. Such pesticides are effective against target pest but pose less hazard to non-target organisms such as natural enemies of pests, pollinators and earthworms.
Some of such pesticides are buprofezin, which is effective against homopterans like planthoppers, neem, Bacillus thuringiensis (Bt), nucleopolyhedrosis virus (NPV) etc.
Earthworms

5. Natural enemies of pests
Pesticides can also be made less hazardous through use of safer formulations such as granules. Pesticide granules like carbofuran 3G or cartap 4G prove effective against rice pests without jeopardizing natural enemies of pests. Pesticide should be strictly used in recommended doses avoiding their overuse and misuse.
Spider
Rove beetle
Stenobracon parasitoid

6. Adverse effects of pesticides can also be reduced by precise placement and proper timing. Foliar application of contact pesticides proves effective against planthoppers only if directed at plant bases and goes waste if carried out on foliage. Likewise, pesticide application against stem borer should coincide with egg hatching. Natural enemies can also be protected through spot application wherein areas with high natural enemy density should not be treated.
Sprayer nozzle directed at plant stems

7. Pesticides recommended against rice pests
Planthoppers
Apply carbofuran 25 kg/ha or
Spray buprofezin 25 ml/ha or imidacloprid ml/ha or chlorpyriphos ml/ha
Stem borer
Apply cartap 25 kg/ha or fipronil 18 kg/ha
Spray cartap 50 g/ha or chlorpyriphos 20 ml/ha or 1250 ml/ha or 100 ml/ha
Planthoppers
Earhead damage due to stem borer

8. Apply endosulfan or carbaryl or malathion dust @ 25-30 kg/ha
Leaf folder
Apply cartap 25 kg/ha or spray cartap g/ha or chlorpyriphos ml/ha or 1250 ml/ha or flubendiamide 100 ml/ha.
Gundhi bug
Spray endosulfan 35 EC or malathion 50 EC or quinalphos ml/ha or
Apply endosulfan or carbaryl or malathion kg/ha
Leaf folder
Gundhi bug

9. Hispa Spray chlorpyriphos 20EC or quinalphos 25 EC or monocrophos ml/ha or Apply carbaryl kg/ha Armyworm Spray chlorpyriphos 20EC or quinalphos ml/ha Apply carbaryl or malathion kg/ha
Hispa beetle
Armyworm larva

10. Economic threshold levels (ETL) of rice insect pests
Brown planthopper (BPH)
6-8 hoppers/hill
Whitebacked planthopper (WBPH)
8-10 hoppers/hill
Stem borer
5% dead hearts or 2% white-ears
or 1 moth/m2 or 1 egg mass/m2
Leaf folder
4% folded leaves
Hispa
4% damaged leaves/hill or 2 adults/hill
Gundhi bug
1 bug/hill
Army worm
1 larva/hill

11. Let’s Sum Up
Sole reliance on pesticides for pest control has created several problems.
Pesticides are important weapons with man against obnoxious pests and
their useful life needs to be prolonged through their judicious application.
Need for pesticide use should be determined through continuous pest
monitoring on crops and should only be used if pest incidence tends to
approach economic threshold level.
Properly timed single pesticide application may very well substitute for
3-4 ill-timed treatments.
Preference should be given selective pesticides that are effective against
target pest but pose less hazard to non-target organisms like neem, Bt etc.
Pesticides can also be made less hazardous through use of safer
formulations such as granules.
Adverse effects of pesticides can also be reduced by their precise
placement.
Natural enemies can also be protected through spot application
wherein areas with high natural enemy density should not be treated.