priciples of insecticide use in rice ipm

Insecticides in Rice IPM (DRR)
recommended insecticides like cartap, monocrotophos, chlorpyriphos etc. are applied during a crop
season. Under these circumstances, there must be slow development of insecticide resistance in this
species. There is no baseline data of insecticides effectiveness against yellow stem borer to judge the
level of insecticide resistance. Even the methodology for detection and quantification of resistance
level to most commonly used insecticides is lacking. Therefore, this should also form a part of research
agenda of insecticide resistance monitoring team of scientists.
l Leaf folder, C. medinalis is another important insect pest from insecticide resistance point of view.
This is becoming serious in traditional areas and also spreading to new areas. Here also insecticides
are the major means of managing the pest. Further very effective insecticides like cartap,
monocrotophos are being widely used. Hence the chances of leaf folder becoming resistant to these
insecticides are high. Therefore, leaf folder should also be monitored for insecticide resistance
development after evolving suitable methodology for detection and determination of base line data.
This can be easily done in institutes where glasshouse facilities are available.
l Basic studies on one or more of these pests regarding the fastness of resistance development,
mechanism of resistance and strategies for management of insecticide resistance have to be conducted,
when there is evidence of resistance development.
l In view of high degree of effectiveness of neonicotinoids and lower cost involved per unit area, these
insecticides are likely to be overused and abused by rice farmers in BPH endemic areas. This will
further hasten the process of resistance development.
l The information available on the practical methods for detecting and monitoring neonicotinoid resistance
in rice planthoppers is inadequate and a lot of research efforts need to go into this aspect.
l The biochemical mechanisms involved and cross-resistance patterns are very poorly understood and
hence emphasis should also be laid on this aspect of neonicotinoid resistance.
l The meager evidence indicates mainly the role of m.f.o. in degrading neonicotinoids in resistant
strains of planthoppers. As m.f.o. are general degrading enzymes for all xenobiotics, it is likely that
there will be cross resistance to other groups of insecticides in neonicotinoid resistant populations of
planthoppers. Hence, this aspect also needs emphasis as a future thrust area of research.
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