Charles A. Mullins, N. B. Shamiyeh, and Renee Follum

Potato yields and quality were generally low, and somewhat typical of potato production in Tennessee. ‘Kennebec’ and ‘LaRouge’ were the more productive cultivars in yield of No. 1 grade tubers.

Potatoes are grown across Tennessee, but acreages are small, and most production is for local fresh market utilization. Extensive trials with potatoes have been conducted at University of Tennessee experiment stations in recent years The potential for potato production appeared to be favorable at the initiation of the trials, but yields were found to be relatively low for economic production for the shipping market. Limited local production for direct marketing appears to be the only potential for potato production. An experiment was conducted at the Plateau Experiment Station at Crossville, TN in 2000 to evaluate performance of seven of the most promising potato cultivars from previous trials.

The site was prepared for planting by conventional tillage methods. Fertilizer was broadcast at 1000 lb/A of 15-15-15 and incorporated with a disk on May 1. Seed stock from Maine was treated with mancozeb (Polyram) before planting on May 1. Imadiclopralid (Admire) was applied in furrow at 1 quart of product per acre. Metolachlor (Dual) at 2.5 lb ai/A and metribuzin (Sencor) at 0.75 lb ai/A were applied on May 1 for weed control Plot size was one row, 20 ft long with 3 ft between rows. Each row contained 40 seed pieces. Experimental plot design was a randomized complete block with four replications. Seven applications of fungicides were applied to the planting. Fungicides used were chlorothalonil (Bravo) at 1.5 lb ai/A plus mancozeb (Dithane DF) at 1.6 lb ai/A alternated with azoxystrobin (Quadris) at 0.1 lb ai/A. One application of esfenvalerate (Asana) at 0.05 lb ai/A was made on June 23.

Harvest was on August 30. Potatoes were graded into No.1, utility, and cull grade; and number and weight of each grade were recorded. All data were analyzed by analysis of variance methods, and means were separated by Duncan’s multiple range tests at the 0.05 level of probability.

Potato yields were relatively low for most cultivars (Table 1). ‘Kennebec’ and ‘LaRouge’ were among the most productive cultivars in yield of No.1 grade fruit tubers as in previous trials. The yield of utility grade tubers was not very high in this trial. ’Superior Newleaf’ produced more culls than all cultivars except ‘Superior’, and ‘Goldrush’. Tubers of ‘Superior’ and ‘Superior Newleaf’ tended to be smaller than most other cultivars, and small size accounted for most of the cull yield of these cultivars. Tubers of ‘Russet Norkotah’ were smoother than tubers of ‘Kennebec’ and ‘LaRouge’.

The trial was not very successful in terms of yield and tuber quality. Wet soil in the early spring delayed planting by two or three weeks past the desired planting date. This trial substainted the general low yield of potatoes in Tennessee compared to major production areas.

Table 1. Yield in tons per acre of No.1, utility, and cull grade fruit; average fruit weight of No. 1 grade and potato cultivars at The University of Tennessee Plateau Experiment Station at Crossville, 2000.