This study, as a survey of farmer’s fields, was conducted in the north-western region of Bangladesh. This region was chosen as the rice false smut disease had been prevalent in the area in last five years (Unpublished data, B Nessa, SSO, BRRI, Bangladesh). Furthermore, this region has been reported to have much variation and diversification of the disease. Within the region, the Natore district was selected through consultation with the Deputy Directors of the Department of Agricultural Extension (DAE), Ministry of Agriculture, Bangladesh, believing that the district will represent the region in terms of the status of the disease. Ninety fields from four unions were sampled. The unions were: Ramananda Khajura and Hatiandah (in Singra upazila), Bagatipara pourasova (in Bagatipara upazila) and Gopalpur pourasova (in Lalpur upazila). From Ramananda Khajura union, 25 fields were selected of which 11, 7, 3 and 4 belonged to Koyapara, Koigram, Ajurdorgah and Chora- Vogirpukur villages, respectively. From Hatiandah union, 32 fields were selected and all the fields belonged to Shalikha village. From Bagatipara pourasova, 19 fields were selected of which 12, 5 and 2 belonged to Broypara, Baroygram-Masimpur and Sonapatil villages, respectively. From Gopalpur pourasova, 14 fields were selected of which 2, 6, 1, 1, 1, 2 and 1 belonged to Bhuianpara, Bijoypur, Mohishakhola, Kesobpur, Choknazirpur, Kalupara and Shibpur villages, respectively. The disease data were collected from five spots, named as blocks, from each field. For this, each of the fields was roughly divided into five blocks located in the upper left side, upper right side, lower left side, lower right side and the middle. From each block, nine hills were randomly selected in a 3×3 matrix. The field survey was conducted during November 2015. This period was chosen because most of the crops were in mid- to late- flowering stage when the disease was visible. Data on total number of panicles per hill, number of infected panicles per hill and number of smut balls per hill were recorded from each sampling block. In addition, planted variety, date of transplanting, seedling age, date of 50% flowering (anthesis) and status (‘yes’ or ‘no’) of foliar fungicide application were recorded for each surveyed field by interviewing farmers. Measured data from five spots were averaged for representing the field on (i) disease incidence (DI) and (ii) number of smut balls per infected panicle (bp): DI (%) = (Number of infected panicle(s); / Total number of panicles) × 100; bp (number of smut balls per infected panicle) = Total number of smut ball(s); / Total number of infected panicles. The flowering times of the crops in the recorded range of 13 September to 1 November were summarized as 5-day interval and corresponding DIs were averaged for each interval. The status of foliar fungicide application was available for 32 fields - 16 each ‘with’ and ‘without’ foliar fungicide application. The DIs for 16 ‘with’ and 16 ‘without’ foliar fungicide application were averaged. The variations in disease incidence, number of smut balls per infected panicle and yield loss for four unions, varieties, times of flowering and effect of foliar fungicide application were statistically analyzed by 95% confidence interval (CI) using Microsoft Office Excel (Nessa et al., 2015b).