HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Miller, J. F. Articles by Gulya, T. J. Search for Related Content PubMed Articles by Miller, J. F. Articles by Gulya, T. J. Agricola Articles by Miller, J. F. Articles by Gulya, T. J.

Inheritance of Resistance to Race 4 of Downy Mildew Derived from Interspecific Crosses in Sunflower

USDA-ARS Oilseeds Res. Unit, Dep. Crop and Weed Sciences

T. J. Gulya

USDA-ARS, Dep. Plant Pathology, North Dakota State Univ., Fargo ND 58105

*Corresponding author.

Race 4 of downy mildew, incited by Plasmopara halstedii (Farl.) Berl. & de Toni, was first reported in sunflower (Helianthus annuus L.) in the USA during 1985. Resistance to this race was found in lines derived from interspecific crosses of cultivated sunflower with three species of wild sunflower. The objectives of this investigation were to determine the genetic control of resistance found in the interspecific crosses and to determine if this resistance was conditioned by the same or different genes. Ratios tested utilizing a chisquare analysis for goodness of fit for F₂ and BC₁F₁ generations indicated that resistance to Race 4 was conditioned by a single, dominant gene in all sources. Four lines (HA 335, HA 336, Charata R4, and Wild Ornamental) were determined to have the same resistance gene PI⁶. HA 335 and HA 336 were derived from wild H. annuus 423 and H. annuus 432, respectively. The resistance gene in HA 339, derived from H. praecox Engelm. & Gray ssp. runyonii, proved to be different and was designated PI⁷. The resistance gene in RHA 340, distinct from PI⁶ and PI⁷ and derived from H. argophyllus Torrey & Gray, was designated PI⁸. Using divergent resistance genes in sunflower commercial hybrids should decrease genetic vulnerability to changes in pathogenicity of downy mildew. However, additional wild species of sunflower should be collected and tested to identify new sources of resistance to downy mildew.

Received for publication January 31, 1990.

This article has been cited by other articles:

				S. Bouterige, R. Robert, J. P. Bouchara, A. Marot-Leblond, V. Molinero, and J. M. Senet Production and Characterization of Two Monoclonal Antibodies Specific for Plasmopara halstedii Appl. Envir. Microbiol., August 1, 2000; 66(8): 3277 - 3282. [Abstract] [Full Text]