Selection for chip quality and specific gravity of potato clones: possibilities for early generation selection

Summary Ten cultivars contrasting in chip quality were grown in the field and in the glasshouse to evaluate three different methods for chip quality assessment. Specific gravity was also measured. The glasshouse culture simulated growth of seedlings and the field culture represented growth of advanced breeding lines. Differences between cultivars for chip quality and specific gravity could be established in both environments. Although ranking of the cultivars in both environments was not identical, both good and bad genotypes could be identified. It seems that mild selection for specific gravity and chip quality among glasshouse-grown seedlings can be exercised. If tubers of glasshouse-grown plants are too small to slice chips, Reflocheck Glucose test strips offer a satisfactory alternative to frying chips. Crip in UK     

Potato chip color,specific gravity and fertilization of potatoes with N−P−K

The effects of fertilizers on potato chip color were studied over a period of 11 years. Yield and specific gravity data also were taken. Single element and compete fertilizers were used in randomized block and split plot experiments. Most of the work was done with the Russet Burbank variety but in some experiments the Kennebec, White Rose, Norgold Russet and Cascade varieties were also included. Specific gravity and chip color data were taken immediately after harvest. Effects of storage and reconditioning on chip color were recorded in some cases. Though statistically significant effects of N?P?K on chip color were found, the differences were small and of no commercial importance. Neither nutrient balance nor total amount of fertilizer used greatly affected chip color whether the tubers were harvested “immature” in July or in October after the vines were dead. The greatest effect of over-fertilization was on the specific gravity of the tubers. As amount of fertilizer applied increased, specific gravity often decreased which would reduce the amount of processed product per unit of fresh produce. Since most manufacturers of processed potatoes prefer high specific gravity tubers perhaps varieties should be grown specifically for the processing industry. Since proper fertilization did not have a commercially important effect on chip color but greatly increased the yield, farmers should fertilize for maximum production when growing potatoes for potato chips.     

Variation in specific gravity of potato tubers

Specific gravity of tubers from the Irish Cobbler, Kennebec, Norgold Russet, Norland, Red Pontiac, Russet Burbank, Snowflake, and Viking varieties grown at 2 locations over 3 years were determined by the brine solution method. The usual differences in specific gravity were noted between varieties and locations. There was a narrow range in specific gravity of individual tubers within lots of Norland and Russet Burbank, and a wide range within lots of Kennebec and Snowflake, with the remaining varieties intermediate. Low variation of tubers within a variety as measured by standard deviation did not indicate low or high specific gravity. Varieties with low variation tended to remain low from one year to the next.     

A simple device for the determination of potato tuber specific gravity

A simple device consisting of a plastic rack with suspended wire basket was developed. This device when used in conjunction with a top loading balance greatly facilitates the determination of the specific gravity of individual tubers.     

The effect of scion and stock autografting and heterografting on specific gravity,sugar content and chip color of potatoes

A potato chipping selection F58050 with high specific gravity and low sugar content and a non-chipping cultivar Sable with low specific gravity and high sugar content were each autografted and cross-heterografted to assess source-sink relationships on specific gravity, sugar content and chip color of potatoes. Heterografting of Sable scions onto F58050 stocks reduced the specific gravity of F58050 tubers compared to autografts of F58050 (P<.05). Grafting of F58050 scions onto Sable stocks did not significantly increase the specific gravity of Sable tubers compared to autografts of Sable. Heterografting of Sable scions onto F58050 stocks resulted in significantly (P<.05) darker chip color but no significant increases in reducing sugar content of potatoes as compared to potatoes from autografts of F58050, both at harvest and after 3 months’ storage at 12 C. On the other hand, potatoes from heterografting of F58050 scion onto Sable stock showed a slight improvement in chip color and significantly (P<.05) lower reducing sugar content than potatoes from autografts of Sable.     

Differences in sugars,chip color,specific gravity and yield of selected potato cultivars grown in michigan

Six cultivars, Atlantic, Eramosa, Kanona, Norchip, Onaway and Saginaw Gold and four selections, MS 700-70, MS 700-83 (Spartan Pearl), MS 716-15 and W-855 (Snowden), were analyzed for sucrose, glucose, chip color, specific gravity and yield at 98 and 138 days in 1988 and 1989, t evaluate their performance to Michigan growing conditions. The average yield of these cultivars at the two harvests for 1988 and 1989 was 46.9 and 54.7 t/ha and 43.1 and 52.3 t/ha, respectively. Eramosa and Onaway were the earliest maturing varieties with low specific gravity, high glucose content and processed into dark colored chips. The glucose and sucrose contents of the remaining eight cultivars at each harvest date were low and produced acceptable chips. The specific gravity of Atlantic, MS 700-70, MS 716-15 and W-855 was in the range of 1.079–1.088 and for Norchip, Kanona and Saginaw Gold the range was 1.071–1.076. The date of harvest, variety and year of production had significant effect (p > 0.01) on yield. The specific gravity, glucose content and chip color were significantly influenced by variety and year of production. The correlation between chip colorvs glucose (r= -0.842, p = 0.000) and harvest datevs yield (r= -0.572, p = 0.000) was also significant.