DURANGO RED

Characteristics Shape: Round Skin: Dark Red Flesh: White Market Use: Fresh Market Medium Maturing

Prepared by Susie Thompson, Ph.D., and Robert D. Davidson, Ph.D., Department of Horticulture & Landscape Architecture, San Luis Valley Research Center, Colorado State University

This profile was developed for production in the San Luis Valley. While some guidelines may be appropriate regardless of growing area, fine-tuning for specific production locales is recommended.

Durango Red is a medium maturing potato cultivar. Release is pending by the Colorado Agricultural Experiment Station. Durango Red is an attractive dark red-skinned cultivar, suitable for the fresh market. It was tested as CO86218-2. Parentage of Durango is Sangre x NDTX9-1068-11R. It has low to medium specific gravity and attractive tuber type. Plant Variety Protection will be applied for.

Plants/roots Durango Red emerges rapidly and has a small to medium and upright vine. Foliage is heavily pigmented and Durango has red-purple flowers. It has a determinate growth habit and a moderate to shallow and concentrated root system.

Tubers are round to slightly oval, with very dark red skin, which is smooth, but not waxy. Flesh is white. Eyes are shallow and more prevalent on the apical end. Specific gravity is low to medium (1.076 average).

Yield potential is medium to high, exceeding 400 cwt./acre.

GROWING SEASON MANAGEMENT

Pre-planting considerations Tubers have medium dormancy. Single drop or cut seed is acceptable. When using cut seed, utilize practices that enhance suberization and prevent decay by pathogens. A 9-inch spacing may optimize total yield, while maintaining a small tuber size profile, although grade components have had similar percentages at a 12-inch spacing. Plant seed about 4 inches deep with a good cover.

Fertility Apply total fertilizer in the range: N(140-160#), P(100-200#), K(0-60#). Pre-plant incorporated N should be from 70 to 90#. Side-dress and sprinkler applied N should be in the 60 to 90# range at a rate of not more than 20# per application. Pear shaped tubers may result if Durango is over-fertilized and adequate or excessive water available. Stolon detachment problems may result if plants are immature due to excessive or late-season nitrogen applications.

Irrigation Interval at the maximum ET is 2.5 days. Drought tolerance is moderate. Water usage will decline as vines mature, so monitor fields to prevent over watering late in the season and potential decay by pathogens such as Pythium or Phytophthora. Enlarged lenticels have frequently been observed when over watered.

Pest control

Weeds Due to small vine size, weed competition may be a problem for some producers. Durango Red has shown sensitivity to metribuzin. Adverse reactions to other commonly utilized herbicides for potato production have not been noted in grower experiences.

Insects Standard insect control measures generally are effective. Use of Di-Syston may result in some foliar phytotoxicity symptoms.

Fungicides Control of foliar early blight usually requires 3 to 4 applications.

Tuber/bulking Durango Red consistently sets about 9 tubers per plant on about 2.8 stems. Tubers are set mid hill. Tuber initiation and bulking rate are medium. Few internal and external defects have been noted. Tubers have moderate resistance to hollow heart and blackspot bruise.

Vine kill Average days from planting to vine kill are 105-110. Sulfuric acid use for vine kill may be warranted to aid stolon breakdown, particularly if plants are immature due to excessive or late-season nitrogen applications or if maturity is delayed due to warm conditions. Adequate skin set occurs at about 18 days.

STORAGE MANAGEMENT

Durango Red stores well and maintains color in storage.

DISEASE REACTION*

Overall disease problems are minimal. Bacterial ring rot foliar symptom expression is adequate and occurs within 90 days after planting. Bacterial soft rot, caused by Erwinia, may be a problem in storage, and in the field as seed piece decay and blackleg. Major potato viruses usually do not present a problem; Durango is similar to Sangre in this regard.

*Disease reaction ratings = susceptible, moderately susceptible, moderate, moderately resistant and resistant.

February 2001

Note: This information should only be used as a guide. Adjustments for local conditions must always be made.