mainly hypophyllous with spots surrounded by light green rings, mostly in groups, confluent, rounded, dark brown, erumpent.
abaxial, yellowish, pulverulent, scattered, minute.
For each leaf on which uredinia
and urediniospore production were to be determined, leaf length and width (each in centimeters) were measured the day of inoculation.
amphigenous, scattered, cinnamon brown, covered by ruptured epidermis, naked, 0.07-0.1 x 0.09-0.2 mm.
more than 800 [micro]m in diameter were found on the unifoliolate leaves of all plants of Nebr.#1 sel.27, indicating that Nebr.#1 sel.27 was susceptible to race 51.
KS00WGRC44 had a lower infection type of 1 (flecks with small necrotic uredinia
) when inoculated with leaf rust race PNM-10,18 at the seedling stage than that observed on the lines TA 4186 (Lr39; IT = 4) and KS90WGRC10 (Lr41; IT = 3C, moderate size uredinia
Compared with Thatcher, which was rated at 90 S (large uredinia
), the Thatcher lines with Lr2a, Lr9, and Lr26 had leaf rust ratings of 20 M, 10 MR (moderate size uredinia
with necrosis), and 30 MR, respectively, in plots at Kinston (Table 1).
Disease infection type was scored by pustule type on each plant with 0 = no macroscopic sign of infection and 4 = large uredinia
and abundant sporulation.
Pustule type (PT) was visually determined by means of a scale from 0 to 4 where 0 = no uredinia
, 1 = chlorotic flecks, 2 = small uredinia
surrounded by necrosis with limited urediniospore production, 3 = medium size uredinia
with moderate sporulation, and 4 = large uredinia
and abundant sporulation (Welty and Barker, 1993).
JB-178 has partial resistance (smaller and fewer uredinia
) to rust [caused by Uromyces appendiculatus (Pets.: Pers.)Unger] in the field in the DR but was susceptible to eight out of nine DR rust pathotypes in a greenhouse test.