Millennium Russet: A Dual Purpose Russet Potato Variety

American Journal of Potato Research, May/Jun 2005 by Groza, H I, Bowen, B D, Kichefski, D, Peloquin, S J, Et al

AGRONOMIC PRODUCTION

Under Wisconsin Central Sands conditions, a wider inrow spacing of plants (>30.4 cm) and a rate of 246.6 kg/ha of nitrogen increased the proportion of Millennium Russet tubers >283.5 g (Cornell et al. 2000). Total yield of Millennium Russet remained constant or tended to decrease as the in-row spacing was increased from 30 to 50 cm (Table 8). However, the yield of tubers 170 g increased as in-row spacing was increased from 30 to 50 cm. Russet Burbank and Millennium Russet had similar total yields in cultural practice trials conducted in Hancock, Wisconsin (data not shown). Millennium Russet tended to have a smaller overall tuber size distribution than Russet Burbank, but had a larger response to increases in in-row spacing than Russet Burbank. The biggest differences in size distribution between Russet Burbank and Millennium Russet were seen in tubers 2800 -g size categories.

Millennium Russet was less responsive to increasing nitrogen rates than Russet Burbank, requiring 10% to 20% less nitrogen for maximum yields. On sandy soils, highest yields were consistently obtained when starter fertilizer (9 to 13.6 kg/ha N) was supplemented with 25% to 35% of the nitrogen applied at emergence, 50% to 60% of the nitrogen applied at mid-tuberization, and the remaining 5% to 35% applied 2 to 3 wk later. On medium-textured soils, nitrogen could be applied in one or two applications. The petiole NO^sub 3^-N data showed that at the economic optimum N rate (EONR), Millennium Russet generally contains about the same NO^sub 3^-N level in the fourth petiole as Russet Burbank, but more than Atlantic when sampled 55 days after emergence (DAE). However, by 70 DAE, petiole nitrate levels at the EONR are higher in both Russet Burbank and Atlantic than in Millennium Russet (Kelling and Speth 2004).

Millennium Russet is not sensitive to metribuzin. Metribuzin applied postemergence at 560.4 g/ha and 1120.8 g ai/ha caused no injury 55 days after planting, but 5% injury was recorded 70 days after planting (Larry Binning and Daniel Heider unpubl data).

CHEMISTRY

The glycoalkaloid content of Millennium Russet was acceptable at 10.44 mg/100 g fresh tissue (4.57 mg/100 g solanine and 5.87 mg/100 g chaconine), in comparison with 8.00 mg/100 g for Russet Burbank, 8.00 mg/100 g for Goldrush, and 5.46 mg/100 g for Russet Norkotah (Kenneth Deahl and Frances Ferez unpubl data).

The isozyme pattern of Millennium Russet is Mdh-1 1^sup 1^1^sup 2^1^sup 2^1^sup 2^, Mdh-2 2^sup 2^2^sup 2^2^sup 2^2^sup 2^, Got-2 2^sup 3^2^sup 3^2^sup 5^2^sup 5^, Got-2 2^sup 3^2^sup 3^2^sup 5^2^sup 5^, Pgm-1 1^sup 1^1^sup 3^1^sup 3^1^sup 3^, Pgm-2 2^sup 2^2^sup 2^2^sup 2^2^sup 2^, Pgi-1 1^sup 2^1^sup 2^1^sup 2^1^sup 2^, 6-Pgdh-3 3^sup 1^3^sup 1^3^sup 1^3^sup 2^ Prx-3 3^sup 1^3^sup 1^3^sub 1^3^sup 1^, where the normal script digit represents the locus and the superscript digit represents the allele for the enzymes malate dehydrogenase (MdK), glutamate oxaloacetate transaminase (Got), phosphoglucomutase (Pgm), phosphoglucose isomerase (Pgi), 6-phosphogluconic acid dehydrogenase (6-Pgdh), and peroxidase (Prx), according to the procedure and nomenclature of Douches and Ludlam (1991).