MORPHOLOGICAL CHARACTERIZATION OF ENDOPHYTIC BACTERIAL STRAINS ISOLATED FROM DISCOLORED RICE GRAIN

Abstract

Various bacterial species were isolated from different rice varieties: Kainat, Basmati-385, Super basmati, Basmati-386, KSK-133, Basmati-198, Basmati-2000x1053-2-2, Kasur, Stg 567989 and Basmati-2000x33797-1 collected from all agro ecological zones of Pakistan. When plated infected grain samples gave various bacterial colonies on Luria Bertani (L.B) agar medium. The isolates were identified on the basis of various morphological and biochemical features. Out of 22 isolates, five showed rod cell shape in microscope. Sixteen biochemical tests were conducted to characterize 22 isolates of bacteria. Gram stain demonstrated that three isolates were gram positive and rod shaped. All other isolates were gram negative. The presence of bacteria was also estimated in ten different varieties of rice. The highest presence of bacteria was observed in KSK-133, Kainat and Stg 567989. Burkholderia species and Enterobacter species have high frequency almost in all tested rice varieties. The overall objective of this study was to screen, classify and associate the bacterial species present on the basis of various morphological characteristics isolated from diverse rice genotype. The results demonstrated that collected and investigated rice varieties have a diverse range of bacterial species, some of which are considered as severe pathogens for plants.