
TY  - JOUR
A1  - Adhikari, K. N. 
A1  - McIntosh, R. A. 
A1  - Oates, J. D. 
T1  - Distribution and temperature sensitivities of genes for stem rust resistance in Australian oat cultivars and selected germplasm
JF  - Australian Journal of Agricultural Research
JO  - Aust. J.  Agric. Res.
Y1  - 1999
VL  - 51
IS  - 1
SP  - 75
EP  - 84
KW  - Avena sativa, Avena strigosa, Puccinia graminis f. sp. avenae, oat stem rust.
UR  - https://doi.org/10.1071/AR99039 
N2  - Seedlings of 40 Australian oat cultivars and 154 elite oat lines were tested with various pathotypes of P. graminis avenae. Fourteen cultivars carried Pg-2 and/or Pg-4. One cultivar carried Pg-13 and 4 carried Pg-a. Several cultivars possessed different combinations of Pg-1, Pg-2, Pg-3, and/or Pg-4, but none possessed Pg-8 or Pg-9. Since most elite lines were resistant to all cultures collected from the pathogenicity survey in 1993 and gave similar low infection types, it was postulated that they all carried a common gene, Pg-a. All isolates from the 1993 survey, except one from northern New South Wales, were avirulent for Pg-a. Studies of the effect of temperature on reaction to stem rust showed that resistances in lines possessing Pg-8 and Pg-16 became ineffective at 21.5&#176;C, but were effective at 17&#176;C. Similarly, resistances in lines possessing Pg-4, Pg-12, and Pg-a were effective at 21.5&#176;C, but became ineffective at or above 26&#176;C. Resistances conferred by Pg-1, Pg-2, Pg-13, and Pg-Sa were not affected by temperature. Although resistance conferred by Pg-a was temperature-sensitive, the retardation of fungal growth with decrease in temperature suggested that increasing day temperatures would not cause the breakdown of this resistance provided night temperatures remain cool. 
ER  -

