Effect of postsymptom application of fungicides on
urediniospore production by Puccinia triticina on wheat and P hemerocallidis on daylily.
Urediniospore and teliospore morphology were consistent with that described for Puccinia emaculata Schw.
The experiment was conducted with two treatments: inoculated (by injecting about 0.2 mL of [10.sup.5]
urediniospore [mL.sup.-1] suspension of isolate 345 of P.
The numbers of
urediniospores of each strain inoculated onto the leaves in each pot were estimated by observing
urediniospore deposition on clear plastic strips in the pots (method described in Inoculation).
6: Scanning electron micrographs of Puccinia sibirica (A)
Urediniospore showing echinulate ornamentation (B) Teliospores showing verrucose ornamentation
Seedlings were screened in the same greenhouse test through two inoculations with stem rust
urediniospores using the conditions,
urediniospore concentrations, and procedures of Welty and Barker (1993).
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).
coronata at the 3 to 4 leaf stage of development (Zadoks growth stage 13-14, Zadoks et al., 1974) by injecting approximately 0.2 mL of a
urediniospore suspension into each stem.
Components of resistance in barley to stem rust: receptivity,
urediniospore production, latent period, and infection response in adult plants.
When the first leaves were fully expanded, the wheat plants were inoculated using a "sweep-dusting" method, sweeping the fully infected leaves of the check Mingxian 169 above the test wheat plants and dusting
urediniospores on them with a very uniform deposit.
UREDINIOSPORES globose to sub-globose, obovoid or ellipsoid or elongated ellipsoid, hyaline to light brown, 20-32.5 x 15-22.5 um, wall 2-2.5 um thick, brown, germ tube hyaline, 4-7 x 3-4.5 um.