MORPHOLOGICAL AND PHYSIOLOGICAL STUDIES OF DIFFERENT RICE BLAST ISOLATES FROM DIFFERENT RICE GROWING AREAS IN PUNJAB, PAKISTAN

Rice blast disease is a major threat main rice growing areas due to its devastating nature and causes huge yield losses annually. The morpho-physiological variation studies of all thirty isolates performed at different temperatures, pH, carbon, nitrogen sources and various growing media i.e. oat meal agar, potato dextrose agar ,2% agar + host seed extract, and Richard basal media. Isolate of SK-5 isolate have maximum colony diameter 38.77mm recorded at 25°C and maximum dry mycelial weight 295.45 mg of SK-4 isolate recorded at the same temperature. At hydrogen ion concentration 6 SK-2 isolate have maximum colony diameter 40.97mm recorded and dry mycelial weight 295.46mg of SK-4 recorded at same hydrogen ion concentration. Isolate of SK-1 isolate have highest colony diameter 85.40mm on glucose and mycelial weight 313.35 of SK-4 isolate recorded at same source. Isolate of SK-3 isolate have highest diameter 85.54mm at the L Glycine nitrogen source and dry mycelial weight of SK-2 isolate recorded 313.35mg. On Richard basal media isolate of SK-3 has maximum colony diameter 81.13mm and SK-5 isolate 80.63mm recorded on oatmeal agar media. Isolate SK-3 has a maximum mycelial weight of 306.56mg in Richard basal media followed by SK-3 isolate 271.44 mg recorded in oatmeal media. These variation indicated that isolates collected from different locations have not morphological similar.