However, it was maximum in the isolate AcHl (9.80 [micro]m), followed by AcBl (9.25 [micro]m), AcAn (8.46 [micro]m) and AcJg (8.15 [micro]m); while, in rest of the four isolates (AcPb, AcWs, AcNd and AcOs) the mycelial width was ranged from 7.05 to 7.81 [micro]m.
However, it was highest in the isolate AcHl (16.43 [micro]m), followed by the isolates viz., AcLt (15.24 [micro]m), AcAk(14.65 [micro]m), AcBl (14.34 [micro]m), AcAn (13.45 [micro]m), AcBd (13.03 [micro]m), AcJg (12.96 [micro]m) and AcAb (12.04 [micro]m).
Of the test isolates, AcBl recorded maximum horizontal (4-12) and vertical (1-3) septations, followed by the isolate viz., AcWs and AcLt (each H:4-8 and V:0-2), AcAk (H:3-8 and V:0-1), AcJl (H:3-5 and V:0-1), AcJg (H:2-6 and V:0-2), AcAn and AcNs (each H: 2-5 and V:1-2) and AcYt (H:2-4 and V: 0-1).
Accordingly, in group A the isolates (04) included were AcHl, AcAn, AcBl and AcJg; in group B the isolates (12) included were AcPb, AcNd, AcSt, AcOs, AcAb, AcWs, AcAk, AcLt, AcBd, AcJl, AcYt and AcSl and in group C the isolates (04) included were viz., AcAm, AcNb, AcDl and AcNs.
In group A of highly virulent isolates the leaf spot frequency was ranged from 15.67 (AcNd) to 22.00 (AcHl) per plant; however, it was significantly highest with the isolate AcHl (22.00), followed by AcBl (21.33), AcAn (19.67), AcJg (18.50), AcPb (16.33) andAcNd (15.67).