Screening tuber-bearingSolanum species for resistance toHelminthosporium solani

Silver scurf, caused byHelminthosporium solani, is an important disease of table stock and processing potatoes, for which few management strategies exist. Two hundred-twelve accessions of tuber-bearingSolarium species were screened for their response toH. solani. Tubers were inoculated in the laboratory with a spore suspension, incubated for 1 mo, and evaluated for infection using the number of conidiophore groups per square millimeter of sporulating tuber surface. Tubers with relatively low sporulation in the laboratory were retested using natural inoculum present in potato storages and assessed for infection. There were significant differences (P < 0.05) between accessions with both methods of inoculation. Some accessions ofSolanum demissum, S. chacoense, S. acaule, S. stoloniferum, S. oxycarpum, andS. hondelmannii consistently demonstrated low sporulation in laboratory and storage, suggesting partial resistance. Both methods of inoculation, laboratory and storage, were found to be correlated (ranging from r = 0.582,P= 0.006; to r = 0.925,P < 0.003).     

Dakchip: A white-skinned chipping cultivar

North Dakota State University announces the name of a new potato to be called Dakchip. Dakchip is a medium maturing cultivar with chip quality quite comparable to Norchip but better than Kennebec. This new cultivar has round to oblong white skinned tubers and has an excellent plant type and growth. Dakchip is comparable to Kennebec in yield but higher than Norchip. Dakchip has moderate resistance to late blight but is susceptible to most potato viruses and some races of scab.     

Differential Rotation and Dynamics of the Solar Interior

Splitting of the sun's global oscillation frequencies by large-scale flows can be used to investigate how rotation varies with radius and latitude within the solar interior. The nearly uninterrupted observations by the Global Oscillation Network Group (GONG) yield oscillation power spectra with high duty cycles and high signal-to-noise ratios. Frequency splittings derived from GONG observations confirm that the variation of rotation rate with latitude seen at the surface carries through much of the convection zone, at the base of which is an adjustment layer leading to latitudinally independent rotation at greater depths. A distinctive shear layer just below the surface is discernible at low to mid-latitudes.     

Goldrush: A new high quality russet-skinned potato cultivar

On March 1, 1992, the North Dakota Agricultural Experiment Station announced the release of a new russet potato cultivar named Goldrush. Goldrush is an oblong, smooth, russet-skinned potato cultivar that has very white flesh, good culinary quality, resistance to hollow heart and is adapted for both the fresh and processing market.     

AC Peregrine Red: A High-yielding Red-skinned Fresh Market Cultivar

AC Peregrine Red is a maincrop cultivar that produces very uniform attractive tubers with a deep red skin color. Marketable yields and skin color retention in storage are superior to Norland in Canadian and some U.S.A. locations. The cultivar provides the fresh market industry with a high-yielding red-skinned potato, with good storage capacity and resistance to fusarium dry rot.     

Russet Norkotah: A new russet-skinned potato cultivar with wide adaptation

Russet Norkotah is a long, smooth, shallow-eyed, russet-skinned potato cultivar with wide adaptation. It has a smooth golden russet-skin and produces a high percent of medium sized U.S. No. 1 tubers that are good count-carton size.