Annual Progress Report on Malting Barley Research March, 2002

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3. Screen breeders lines for resistance to net blotch. 400 breeder’s lines were
screened for net blotch (Pyrenophora teres f. teres) resistance in the greenhouse
last year. Ninety eight out of 219 tested 2-rowed lines were found to have good to
high levels of resistance (with infection types 4. 3, 2, or lower). Among the 6rowed
lines, half of them only exhibited a moderate level of resistance to net
blotch, only lines ND19711, ND 19742, and ND19289 exhibited low infection
phenotypes to isolate 89-19 of P. teres f. teres. These results confirmed previous
screening which clearly showed that in lines originating from the the breeding
programs at NDSU, 2 row barley has greater resistance than 6 row.
4. Screen barley for resistance to crown rust. A further study was conducted for
the genetics of resistance to barley crown rust (Puccinia coronata var. hordei) in
wheat.. F2 populations, derived from Chris monosomic wheat lines crossed to a
spring type susceptible selection of PI350005, were inoculated with crown rust
isolate 91-36sp1. The disease reactions of the F2 progenies fit closely to the
expected single gene ratio and the phenotype data was provided for the on-going
molecular mapping of the resistance gene in wheat.
Several barley lines were evaluated for their resistance to crown rust in the field.
Logan, PC249a, and Hor2596 were found resistant to crown rust with reaction
types of MR or R. Aim and Azure are susceptible to crown rust in the field.
5. Molecular mapping of the barley stem rust resistance gene rpg4. In a
collaborative effort on physical mapping of the barley stem rust resistance gene
rpg4 , barley pathology project of NDSU has screened 100 OS6 x Harrington F2
families and SQ501 derivatives to pathotype QCC-2 of Puccinia graminis f. sp.
tritici at both low and high temperatures. In addition, 102 recombinant barley
families for rpg4 resistance were also tested against pathotype QCC-2. Analysis
is ongoing.
6. Verifying the existence of new spot blotch races. With Dr J Frankowiak we
have screened 46 diverse genetic barely lines in the glasshouse against 3 putative
new races of Cochliobolus sativus that caused much higher levels of disease in the
field in 2001. Preliminary results indicate that these are new races that are able to
cause increased disease.
OTHER FUNDS AND FUTURE DIRECTIONS
As one of the principal investigators on the SBARE Malting Barley for Western North
Dakota project I have developed collaborations with Dr Marcia McMullen and Mr Roger
Ashley to substantially increase the numbers of barley fields sampled for leaf, stem head
and root diseases in Western North Dakota. Currently about 190 barley fields are
sampled annually with patchy distributions in some parts of the state. We aim to increase
the sampling to 500 fields. This sampling will not only provide spatial data that will be
available to farmers and researchers about actual problems in the field but will provide
the project with a bank of isolates that can be used to monitor pathotype distributions.
The money allocated from SBARE does not fully cover the anticipated project
expenditure.