Abstract:
The experiment was conducted at the experimental field of Bangladesh Agricultural
Research Institute (BARI), Gazipur during the period from November 2007 to April
2008 to find out the effect of fungicide and salicylic acid for controlling leaf spot and
rust diseases of groundnut. The variety Dhaka-l was selected for this study as a test
crop. Consequently three experiments were conducted. Experiment-It Evaluation of
fungicides in controlling leaf spot and rust diseases of groundnut. The experiment
comprised treatments- T,: Predator (propiconazole, 0.5 ml/L); T2: Blezole
(hexaconazole, 1 mIlL); T3: Magnate (mancozeb, 500-625 glha); T4: Cluster
(mancozeb+carbendazim, 2g1L); r; Ezeb (rnancozeb, I gIL); T6: Detail
(hexaconazole, 0.5mIIL); T7: Tan (propiconazole, O.SmllL); Tg: Contaf (hexaconazole,
1mIIL) and T9: Control. Experiment-2: Minimum spray of fungicides in controlling
leaf spot and rust diseases of groundnut. The experiment comprised treatments- T1:
One spray at 105 DAS (Blezole); T2: One spray at 105 DAS (Contaf); T3: Two spray
at 105 and 120 DAS (Blezole); T4: Two spray at 105 and 120 DAS (Contaf); Ts:
Three spray at 90, 105 and 120 DAS (Blezole); T6: Three spray at 90, lOS and 120
DAS (Contat) and T7: Control. Experiment-3: Effect of Salicylic Acid in controlling
leaf spot and rust diseases of groundnut. The experiment comprised treatments- Tt:
Control; T2: 0.5 mM salicylic acid foliar spray; T3: 1.0 mM salicylic acid foliar spray
and T4: 1.5 mM salicylic acid foliar sprays. Disease data, yield contributing characters
and yield showed significant variation for different fungicides. In case of leaf spot
disease, at 90, 105 and 120 DAS the minimum disease severity (1.00%, 2.10% and
2.47%) was recorded from Tg and the maximum disease severity «4.60%, 6.15% and
7.60%) was found from T9. In case of rust, at 90, lOS and 120 DAS the minimum
disease severity (1.85%,4.05% and 3.00%) was recorded from Tj again, the maximum
(5.40%, 8.25% and 9.60%) was found from T9. The highest yield (2.38 t/ha) was
found from Tg, and the lowest (1.40 t/ha) was recorded from T9. Disease data, yield
contributing 'characters and yield showed significant variation for different number of
spraying of fungicides. In case of leaf spot disease, at 90, 105 and 120 DAS the
minimum disease severity (1.14%, 1.21% and 1.90%) was recorded from T6, whereas
the maximum (3.30%, 4.51% and 7.93%) was recorded from T7• In case of rust, at 90,
105 and 120 DAS the minimum disease severity (2.36%, 3.22 % and 1.90%) was
recorded from T6, whereas the maximum (4.49%, 6.15% and 9.73%) was recorded
from T7. The highest pod yield (2.44 t/ha) was recorded from T6, while the lowest
yield (1.11 t/ha) was found from T7. Disease data, yield contributing characters and
yield showed significant variation for different concentration of salicylic acid. In case
of leaf spot disease, at 90, 105 and 120 DAS the minimum disease severity (0.63%,
1:25% and 1.84%) was recorded from T4 and the maximum (2.06%, 3.59% and
4.19%) was recorded from I). In case of rust, at 90, 105 and 120 DAS the minimum
disease severity (1.46%, 2.07% and 2.29%) was recorded from T4 and, the maximum
(3.04%, 5.30% and 6.39%) was recorded from T,. The highest pods yield (2.47 t/ha)
was obtained from T4, while the lowest (1.86 t/ha) was recorded from T,.