Fungicidal effect of Azadirachta indica extracts against pathogenic fungi Rhizopus stolonifer and Monilinia fructicola in postharvest peaches
摘要
The study reports the fungicidal effects of Azadirachta indica (neem) flower plus root ethanolic and aqueous extracts. Several parameters were assessed against post-harvest pathogenic fungi (Rhizopus stolonifer and Monilinia fructicola). These parameters include mycelium inhibition, spore germination inhibition, mycelium dry weight, lesion diameter, peach rot incidence, and disease severity. The ethanolic extract of flower showed maximum spore germination inhibition (80 ± 02%) and consequently highest mycelium growth inhibition of 71.25% against Rhizopus stolonifer as compared to aqueous extract. The ethanol flower extracts (500 mg/mL) exhibited lowest mycelium dry weight when the extract was tested against R. stolonifer. The disease incidence after 7 days incubation of peaches treated with flower ethanol extract was 18.52 ± 0.5 and 24.07 ± 0% against R. stolonifer and M. fructicola respectively. The lesion diameter on the surface of treated peach fruits increased with increase in incubation time. A minimum diameter of about 0.6 cm of a lesion was calculated against R. stolonifer in case of ethanolic extract of flower. The peach rot disease severities caused by R. stolonifer and M. fructicola after 7 days treatment with flower ethanol A. indica extract were found to be 25 ± 0 and 39.13 ± 0% respectively. The ethanol and aqueous extracts of the selected plant showed varying levels fungi toxicity that could be effectively used in minimizing crop losses. The results reflect attention of farmers toward A. Indica based extracts to be utilized as bio-fungicide for the prevention of various fungi in fruits during post- harvest conditions.