Too long incubation may lead to poor expression of resistance to rust fungi in barley

Table 1. Infection density (average number of mature pustules per leaf or per cm2) of Puccinia triticina isolate Flamingo on seedling leaves of seven barley lines, and on the host wheat line 8860, observed ten days after inoculation, and incubation under three regimes.

 

 

Barley line

Treatment

Dew chamber

 

Compartment

17.5 h incubation

9.5 h incubation

 

9.5 h incubation

Volla

9.3 per leaf

0 per leaf

 

0 per leaf

Varunda

5.3 per leaf

0.3 per leaf

 

0 per leaf

Freegold

8.7 per leaf

0 per leaf

 

0 per leaf

Valeta

4.3 per leaf

0 per leaf

 

0 per leaf

L100

 

157.3 per leaf

38.0 per leaf

 

34.0 per leaf

L92

37.4 per cm2

3.4 per cm2

 

7.0 per cm2

L94

29.2 per cm2

1.8 per cm2

 

2.3 per cm2

 

8860 (wheat)

 

76.6 per cm2

 

63.5 per cm2

 

 

77.1 per cm2