NON-CHEMICAL APPROACHES FOR THE MANAGEMENT OF ...

6. SUMMARY AND CONCLUSION
Investigations on non-chemical approaches for the management of shoot fly in kharif
sorghum were undertaken in order to tailor a suitable management strategy against shoot fly.
The present investigations were carried out at Main Agricultural Research Station, University
of Agricultural Sciences, Dharwad during 2008. The results obtained from the present studies
are summarized here under:
Effect of seed treatment with organics on oviposition shoot fly revealed that NSKE
(5%), Azagro (5%), neem oil (2%) and plant mixture (5%) offered least egg load per plant in
sorghum and were on par with chemicals. Cow urine (5%), vermiwash (5%), Vitex negundo
leaf extract (5%) and castor leaf extract were inferior treatments similar to untreated check.
However, all the other botanical seed treatments were superior over untreated check.
Evaluation of seed treatments with organics against shoot fly in sorghum revealed
that NSKE (5%), Azagro (5%), neem oil (5%) and plant mixture (5%) were best of all organics
offering least dead heart percentage due to shoot fly. But these were inferior to chemical
seed treatment V. negundo leaf extract (5%), garlic bulb extract (5%) and Annona squamosa
leaf extract (5%) were least effective treatments and cow urine (5%) vermiwash (5%), castor
leaf extract (5%), jatropha leaf extract (5%) and jatropha oil (2%) were ineffective as that of
untreated check. In late sown sorghum, highest protection against shoot fly was offered by
NSKE (5%), Azagro (5%) and neem oil (2%). But those were inferior to chemicals. Garlic
bulb extract (5%) and jatropha leaf extract (5%) were inferior to other botanicals and cow
urine (5%) ad vermiwash (5%) was ineffective as that of untreated check.
Highest grain yield of sorghum was obtained in NSKE (5%), Azagro (5%), neem oil
(2%) and plant mixture (5%). However these treatments were inferior to chemical seed
treatments. Lowest yield was recorded in cow urine (5%), vermiwash (5%), castor leaf extract
(5%), jatropha leaf extract (5%), jatropha oil (2%) and untreated control. Similar trend was
noticed in late sown sorghum where highest yield recorded in NSKE (5%), neem oil (5%) and
plant mixture (5%). But these treatments were inferior to endosulfan and imidacloprid. Lowest
yield was recorded in cow urine (5%), vermiwash (5%), castor leaf extract (5%), jatropha leaf
extract (5%), jatropha oil (2%) and untreated control. Remaining all seed treatments were
superior to untreated control.
Study on effect of organic seed treatments on coccinellid population in timely sown
sorghum revealed no statistical differences in coccinellid population per plant on 14, 21 and
28 DAE. All organic treatments were on par with untreated control in conserving coccinellid
predators. Also, in late sown sorghum, same trend was observed.
Study on evaluation of organic seed treatments on chrysoperla population in timely
and late sown sorghum revealed that on 14, 21 and 28 DAE all organic seed treatments
conserved same chrysoperla population per plant as that of untreated check.
Cost economics for the management of sorghum shoot fly through seed treatments
indicated that highest net returns were obtained in neem oil 2 per cent treatment but
Endosulfan and Imidacloprid remained superior recording highest net returns than organics.
Also among organics, highest IBC ratio was obtained in NSKE 5 per cent seed treatment.
However, chemicals (Endosulfan and Imidacloprid) remained superior recording higher IBC
ratio than all other organics used.
Effect of spraying botanicals at various intervals on shoot fly oviposition on 14 DAE in
normal sown sorghum revealed that the Azagro (5%) and NSKE (5%) were superior over
plant mixture (5%) recording less egg load per plant. But these were inferior to endosulfan
spray. All spraying intervals irrespective of treatments were superior over untreated check
and best results were obtained with spraying at 3, 6, 9, 12 DAE and least with spraying at 3
DAE and 12 DAE.
Interaction effect revealed that spraying Azagro (5%) at 3, 6, 9 DAE, 3, 6, 9, 12 DAE
and 6, 9, 12 DAE, spraying NSKE (5%) at these intervals and spraying plant mixture (5%) at
3, 6, 9, 12 DAE were best treatments as that of spraying endosulfan at these intervals. On 21
DAE also NSKE (5%) and Azagro (5%) were superior to plant mixture inspective of spraying
internvals but were inferior to endosulfan. All spraying intervals irrespective of treatments
were superior to untreated check but best results given by spraying at 3, 6, 9, 12 DAE which