ASSESSMENT OF SEEDBORNE MYCOFLORA OF SUNFLOWER (Helianthus annuus L.)

Abstract

An experiment was conducted in Dr. M. A Wazed Miah Central laboratory, Department of Plant Pathology, Faculty of Agriculture, Sher-e-Bangla Agricultural University, Sher-e-Bangla Nagar, Dhaka-1207 during the period from June’ 2020 to December’ 2020 to detect, identify and isolating associated mycoflora in three varieties of sunflower for fullfilling the objectives with five methods viz., Blotter paper pethod, Deep freezing method, Washing test, PDA media method and Water agar plate method were used. The experiment was laid out in Completely Randomized Design (CRD) with three replications for all methods. The species composition, percentage of seed infection and seeds germination percentage differed among cultivars as well as method. A total of 9 different fungal species belonging to six genera were detected from sunflower seed through five different methods. Among them BARI Sunflower 3 showed the highest infection in washing test compared to other methods. A number of fungi isolated in the present study specially those in the genera viz. Alternaria sp, Curvularia sp, Aspergillus sp, Fusarium sp, Rhizopus sp, and Stemphyllum sp are known to be potent mycoflora producers. Among the fungi detected, frequency of Alternaria alternata was found significantly the highest in the all methods. The highest percentage of germination was found in BARI Sunflower 3 (86.67%) by Blotter paper method. The highest percentage of infection was found in BARI Sunflower 3 (73.33%) in both Blotter and Washing test and the percentage of dead seed after incubation was least in BARI Sunflower 3 (13.33%) by Blotter paper method. Of the five methods tested for detection of seedborne mycoflora, Blotter paper, PDA media, and Washing test were highly effective for mycoflora study.