priciples of insecticide use in rice ipm

Insecticides in Rice IPM (DRR)
iii) STEM BORERS
Among the stem borers that infest rice crop in India, yellow stem borer Scirphophaga incertulas is the
most important. This insect is not amenable for artificial rearing in the laboratory. Rearing under greenhouse
conditions on its natural host, rice plant, has limited scope for mass multiplication, owing to requirement
of huge space, long time and big effort even to get very limited insect culture. Hence, the information on
insecticide efficacy against yellow stem borer has been generated under field conditions. However, under
field conditions along with YSB, other stem borers like white stem borer S. innotata, dark headed borer
Chilo suppresalis, and pink stem borer Sesamia inferens are also present. As the symptoms caused by
these different stem borers in vegetative phase (dead hearts) and heading phase (white ear heads) are
similar, the effectiveness of insecticides reported in the literature reflects on the totality of stem borer
complex and not necessarily to yellow stem borer alone. Along with stem borer, other pests like leaf folder
and gall midge are also present in certain situations.
GRANULAR FORMULATIONS
Both granular formulations and spray formulations were extensively evaluated against stem borer.
Subramanian et al., (1981) observed that BPMC granules at 2 kg a.i./ha were at par with standard check
carbofuran (0.75 kg a.i./ha). BPMC was effective in Philippines (Heinrichs et al., 1986). Chlorpyriphos 5G,
carbofuran 3G and diazinon 10 G were effective against over-wintering larvae in Pakistan (Ul-Haq and
Inayatullah 1990). Gubbaiah et al., (1995) reported that cartap 4 G at 0.75 kg a.i./ha was at par with
carbofuran 0.6 kg a.i./ha. Krishnaiah et al., (1996) reported that granules of ethoprophos and isazophos
in addition to cartap (each at 1 kg a.i./ha) were more effective than the check insecticide carbofuran
against stem borer and also leaf folder. Khan and Khaliq (1989) from Pakistan confirmed the effectiveness
of cartap granules. Sontakke and Dash (2000) observed that chlorpyriphos granules (1kg a.i/ha) were
effective against stem borer. Krishnaiah et. al. (2003a) reported that carbosulfan (1 kg a.i./ha) was also
as effective as check insecticide carbofuran (1 kg a.i./ha) against this pest.
SPRAY FORMULATIONS
Among the spray formulations, furathiocarb, pyridaphenthion, BPMC (0.75 kg a.i./ha) and ethofenprox
(0.05 kg a.i./ha) were moderately effective against stem borers while, pyridaphenthion and ethofenprox
exhibited moderate effectiveness against leaf folder and were similar to chlorpyriphos (0.5 kg a.i./ha)
(Krishnaiah et al., 1996). Triazophos and two new formulations of quinalphos (20 AF and 20 CS) at 0.5
kg a.i./ha were found effective against stem borer. Later studies (Krishnaiah et. al. 2003a) indicated that
the combination product viz., acephate 45% + cypermethrin 5% (500 g a.i./ha); beta cyfluthrin 1.25%
+ chlorpyriphos 25% at 393 g a.i./ha; BPMC 23% + chlorpyriphos 33 % at 550 g a.i/ha and BPMC 30%
+ fipronil 1% (at 310 g a.i/ha) were at par with standard check monocrotophos against stem borer and
leaf folder. Dash and Mukherjee (2003) observed that silafluofen at 0.1 kg a.i./ha was at par with check
insecticide chlorpyriphos (0.5 kg a.i./ha) against stem borers. Misra and Parida (2004) screened several
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