Abstract:
Effect of seed treatment with Bien (Benzothiadiazole), Amistar (azoxystrobin) and
Vitavax-200 (Carboxin) on germination, prevalence of seed borne fungi, seedling
mortality, tikka disease of peanut var. Dhaka 1 and Jhinga badam were investigated in the
laboratory and field laboratory, Department of Plant Pathology, Bangladesh Agricultural
University, Mymensingh during the period of July 2002 to May 2003. Seed health test by
blotter method revealed that the seeds of peanut var. Dhaka I yielded Aspergillus niger
(19.0%), A. flavus (18%), Sclerotium 1"0[(sii(2.33%), Fusarium spp. (5.0%), Rhizoctonia
solani (2%), Macrophomina phase a/ina (3.0%) and Penicillium spp. (1.67%) and seeds of
Jhinga badam yielded Aspergillus niger(19.3%) A. flavus (12.33%), S. rofsii (0.67%),
Fusarium spp. (2.67%), R. solani (2.33%), M. phaseolina (3.33%) and Penicillium spp.
(2.0%). Seed treatment with Bion (0.005% and 0.01 %), Amistar (0.05% and 0.1 %) and
Vitavax-200 (0.3% of seed weight) reduced prevalence of seed borne fungi on blotter.
Amistar and Vitavax-200 showed best performance in controlling seed borne fungi. Bion
(0.01%), Amistar (0.05%) and Vitavax-200 (0.3% of seed weight) completely inhibited
the prevalence of seed borne Sclerotium and Fusarium of peanut var. Dhaka 1 and Jhinga
badam. Moreover, Amistar (0.1%) and Vitavax-200 (0.3% of seed weight) strongly
inhibited the prevalence of seed borne Rhizoctonia solani, Macrophomina phaseolina and
Penicillium spp. Challenge test with Aspergillus niger showed that none of the tested
chemicals had the ability to protect crown rot (Aspergillus niger) of peanut, whereas
Vitavax-200 exerted best performance to control Sclerotium rolfsii and increased
germination and decreased post emergence seedling mortality. Amistar showed better
performance to control Fusarium oxysporum and increased germination and decreased
post emergence death of seedlings. Vitavax-200 gave better performance and increased
germination and decreased post emergence mortality in both the peanut varieties under
field condition. Bion showed better performance regarding tikka disease (Cercospora
arachidicola and Cercosporidium personatum) in reducing number of diseased leaflets
/plant and incidence of leaf infection at first counting (110 days after sowing). Amistar
were found to be effective to reduce number of diseased leaflets/ plant, percent leaf
infection and percent leaf area diseased. Bion increased pod yield/plant and kernal
yield/plant of peanut var. Dhaka ] and Jhinga badam by upto 27.06% and 32.33%,
whereas Amistar 69.1% and 90.41% and Vitavax- 200, 39.47% and 52.36% over control,
respectively.