EVALUATION OF DIFFERENT BOTANICALS AND BIOLOGICAL AGENTS TO CONTROL CERCOSPORA LEAF SPOT OF INDIAN SPINACH

Abstract

The experiments were conducted at the experimental field and laboratory of Plant Pathology and Seed Science Department, Sylhet Agricultural University, Sylhet to explore the prevalence of seed-borne fungal pathogens and their response to botanicals and biological agents. In laboratory experiment, by using Blotter method, the collected seed sample was treated with five different treatments like T2: Custard apple leaf extract (1:2 w/v), T3: Neem leaf extract (1:2 w/v), T4: Biskatali leaf extract (1:2 w/v), T5: Mahagoni leaf extract (1:2 w/v) and T7: control. Different fungal pathogens were detected from the collected seed sample namely Fusarium oxysporum, Alternaria sp., Rhizopus stolonifer, Curvularia sp., and Cercospora sp. The treatment T4 (Biskatali leaf extract) was found to be most effective in controlling seed borne fungi followed by T3 (Neem leaf extract). In case of field experiment, similar five treatments were used as seed treatment along with another two treatments like T1 (Trichocompost) and T6 (Decomposed cowdung) which were used as soil treatment. The four treatments of leaf extracts were also used with concentration 1:4 (w/v) as spray solution in field condition. The lowest disease incidence (28.9%) and disease severity (14.4%) were found in treatments Tı (Trichocompost) and gave best result in term of yield (8.9 t/ha). Treatment T4 (Biskatali leaf extract) and T6 (decomposed cowdung) also gave satisfactory result in yield and found effective to control Cercospora leaf spot of Indian spinach compared to other treatments. The results of the present studies suggested that, use of biological agents (Trichocompost) and botanical treatments especially Biskatali leaf extract has ability to minimize Cercospora leaf spot disease and increase its yield.