CalRed

Description
Tuber Shape Round
Eyes Shallow evenly distributed eyes
Skin Red
Flesh White
Plant Medium sized upright vine with red-purple flowers
CalRed was selected in 1981 from a cross between Bison and Sangre at UDSA in Aberdeen, Idaho and formally named A79543-4. It was named and released by the University of Calofornia in 2000. Calred is an early to medium maturing, fresh market red potato. The tubers have a bright red skin color that does not fade in storage. The tuber skin has a pleasing shiny surface. It tends to have a high very evenly sized set of round tubers that have a low suceptibility to internal and external defects. It has shown some tolerance to powdery scab. It can have problems with post harvest tuber decay so care should be taken in the early storage period.

Plant/roots This cultivar is slow emerging with a medium vine and red-purple flowers. CalRed has a determinate growth habit and a moderate to shallow, concentrated root system.

Tubers are white fleshed, round and smooth with a bright red skin color; eyes are shallow and well distributed; medium for reds specific gravity (1.077).

Yields potential 300 to 400 cwt. range.

GROWING SEASON MANAGEMENT

Pre-planting considerations Tubers have a medium dormancy; either single drop or cut seed is acceptable. When using cut seed, be aware of the potential for serious seed piece decay caused by Erwinia bacteria. Adequate warming of seed (at least seven to 10 days at 65 F) prior to planting is useful for better uniform emergence. Relatively close seed spacing may help optimize yield and tuber size. Plant seed 2 to 4 inches deep with a good hill cover.

Fertility (soil test basis; lbs/acre)

Apply total fertilizer in the following range: N(l30-160#), P(l20-200#), K(O-60#). Performance in alkaline soils is good. Pre-plant incorporated N should be from 90 to 100#. Early season N applications do not adversely affect the timing of tuberization. Sprinkler or broadcast applied N should be in the 40 to 60# range at a rate of 20# per application.

Irrigation Irrigation interval at the maximum ET is 2.5 days. Drought tolerance is moderate. Water use drops dramatically during vine maturation, so careful monitoring is essential to prevent late season overwatering and potential tuber decay caused by Pythium and Phytophthora.

Pest control

Weeds: Competition against weeds is good.

Insects: Standard insect control measures generally are effective.

Fungicides: Control of foliar early blight usually requires two to four fungicide applications.

Tuber/bulking: Tuber set is heavy, somewhat shallow and localized in the hill. Tuberization occurs early and tubers bulk at a rapid rate early in the season. Tuber size in this variety tends to be very even. Tubers are resistant to second growth and moderately resistant to hollow heart, growth cracks and blackspot.

Vine kill: Average days from planting to vine kill are 95 to 105. Vine killing is required in most years; can be easily accomplished once mature. Good skin set occurs within 18 to 22 days.

STORAGE MANAGEMENT

CalRed stores well with few problems and sprouting is minimal. CalRed's red color does not tend to fade during long-term storage.

DISEASE REACTION

Overall disease problems are minimal. Bacterial ring rot foliar symptom expression is intense and occur 70 to 80 days after planting. Tuber symptoms often accompany foliage expression. Erwinia caused bacterial soft rot can be a problem in storage if foliage blackleg incidence is high, but this is not a common problem.

This cultivar rarely has problems with viruses in the field because of low aphid preference.
Field Storage
Foliar early blight: Moderate susceptible Tuber early blight Moderate Resistant
Verticillium wilt: Moderately Susceptible Bacterial soft rot Moderate
Blackleg Moderate Fusarium dry rot Moderately susceptible
Seedpiece decay Moderate Leak (Pythium) Moderately Susceptible
Leafroll virus Moderately Resistant Pink rot (Phytophthora) Moderately Susceptible
Leafroll Net necrosis Resistant Silver scurf Moderately Susceptible
PVY, PVX Moderate Rhizoctonia scurf Moderately Susceptible
Bacterial ring rot Susceptible
Common Scab Moderately Resistant

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

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