Table 1.   Field responses of durum wheat (DW) and bread wheat (BW) lines to stem rust 

Crop season

Wheat species

 (Total lines)

       Percentage of total lines

Resistant

%

lines

MS

  Percent of total lines

Susceptible

F            R          MR        X

<5S       5S - 30S       >30S

1999-2000

  DW (211)

  0.5

  0.9

  6.6

0.0

15.2

5.7

46.1

25.1

  BW (1151)

18.5

30.1

45.4

0.1

  2.7

0.7

  1.8

  0.6

1998-99

  DW  (232)

  0.0

  0.0

  2.1

0.4

  6.9

8.6

52.7

29.3

  BW  (1138)

39.4

  5.6

39.2

0.0

  5.0

5.3

  4.5

  1.0

1997-98

  DW  (216)

  1.8

  3.2

13.9

0.0

10.6

9.7

41.7

19.1

  BW  (1001)

  6.2

  8.9

68.9

0.1

  7.2

3.0

  3.7

  2.0

1996-97

  DW  (185)

  0.0

  0.0

  4.3

0.0

15.1

1.6

21.6

57.4

  BW  (1139)

  1.0

19.3

62.0

0.0

  5.8

0.9

  3.9

  7.1

(Total No. of  lines)  

Means of four crop seasons

  DW  (844)

  0.6

  1.0

  6.7

0.1

11.9

6.4

40.5

32.7

  BW  (4429)

16.3

16.0

53.9

0.05

  5.2

2.5

  3.5

  2.7

Reaction Classes: F- freedom from infection (no uredia),  R- resistant (minute uredia with necrosis),  MR- moderately resistant (small uredia with necrosis / chlorosis),  MS- moderately susceptible (medium sized uredia with or without necrosis / chlorosis),  Susceptible- large uredia without any necrosis / chlorosis,  X- mesothetic response (all kinds of uredia present together)

Susceptible Reaction Class further sub-classified:   <5S – low level of susceptibility (terminal rust severity affecting less than 5% of the host tissue),  5S-30S – intermediate level of susceptibility (terminal rust severity affecting 5-30% of the host tissue),    >30S – high level of susceptibility (terminal rust severity affecting more than 30% of the host tissue)