An Investigation on Disease Incidence, Grain Yield and Quality of BRRI Dhan29 in Bangladesh

Ismail Hossain,Md Mahbubul Alam,Muhammad Abdus Sobahan,Nasima Akter

doi:10.3126/ijasbt.v4i3.15151

Abstract

Rice crops are susceptible to disease, which causes large yield losses in many Asian countries. The influence of disease incidence and severity on grain yield and quality of the rice (Oryza sativa L., cv. BRRI dhan29) was investigated in three different locations of Chief Farm Superintendent’s (CFS) farm viz. Near Weather Yard (location-1), Near Agronomy Farm (location-2) and Near CFS farm office (location-3), Bangladesh Agricultural University (BAU), mymensingh, Bangladesh during boro season. In location-1, both brown spot and sheath blight were recorded whereas in location-2 and in location-3 only brown spot was recorded. Severity of brown spot was lowest at the location-1 and the highest at the location-3. Combined incidence of brown spot and sheath blight decreased the yield considerably whereas brown spot did not alone. Maximum severity of sheath blight was observed both in flowering and soft dough stage and minimum at maximum tillering stage. The lowest infection index of brown spot was obtained at maximum tillering stage and the highest infection index was obtained at soft dough stage whereas maximum and minimum infection index of sheath blight of rice were recorded at soft dough stage and maximum tillering stage, respectively. Aparently healthy seeds, spotted seeds, discoloured seeds, deformed seeds and chaffy grains were found among the three locations. Germination percentage was highest in healthy seeds compared to other category seeds. Alternaria padwickii, Alternaria tenuis, Bipolaris oryzae, Curvularia lunata and Fusarium semitectum were found to be associated with the seed. The highest and lowest occurrence of A. padwickii, A. tenuis, B. oryzae, C. lunata were recorded from chaffy grains and from healthy seeds, respectively. It is suggest that disease incidence and severity was gradually increased with the age of the plant and reduced yield and quality of BRRI dhan29. Int J Appl Sci Biotechnol, Vol 4(3): 311-317

Highlights

Rice (Oryza sativa L.) is the most important cereal crop in Asia producing about 90% of the world production (IRRI, 2008)
Health quality of rice seed is quite poor in the country. Considering these views, in this study, we investigated the disease incidence and severity of rice and their impact on yield, intensity of different seed-borne fungi and germination of BRRI dhan29
Disease incidence and severity of BRRI dhan29 were recorded in three locations at different growth stages viz. maximum tillering, booting, panicle initiation, flowering and soft dough (Table 1)

Summary

Introduction

Rice (Oryza sativa L.) is the most important cereal crop in Asia producing about 90% of the world production (IRRI, 2008). Considering these views, in this study, we investigated the disease incidence and severity of rice and their impact on yield, intensity of different seed-borne fungi and germination of BRRI dhan29. The severity of two diseases viz., brown spot and sheath blight were recorded following IRRI recommended grading scale (Standard Evaluation System for Rice).

Results

Conclusion