CRESTONE RUSSET

Crestone is an early-maturing fresh market potato released in 1993 by Colorado State University (contact the San Luis Valley Research Center for additional information).



Plant/roots Medium, semi-prostrate vine and purple flowers; determinate growth habit; moderate, spreading root system.



Tubers are white fleshed, oblong to long, somewhat flat with a light russet skin. Eyes are shallow, numerous and well distributed; tubers have low specific gravity (1.074).



Yield potential 400 to 450 cwt. range with a high percentage of No. l's.



GROWING SEASON MANAGEMENT



Pre-planting considerations Tubers have medium dormancy; whole or cut seed is acceptable; eyes near the stem end may sprout later than those near the bud end. Erratic emergence can result if inadequate warming of seed takes place. Seed piece decay can be a problem if poor quality seed is used. Plant this cultivar 2 to 4 inches deep. Crestones have had problems with seed piece decay and taking some preventative steps can greatly reduce this problem. Pre-cut seed and suberize it well. It's better to plant into moist soil and not cover the seed too deeply, then don't irrigate after planting. Drag Crestones off sooner to help them emerge.



Fertility (soil test basis; lbs/acre)

Apply total fertilizer in the following range: N(l20-160#), P(l20-200#), K(060#). Performance in alkali soils is excellent. Pre-plant incorporated N: should be 90 to 100#. Early season N applications do not adversely affect the timing of tuberization. Sprinkler applied N should be in the 60 to 90# range at a rate of 20# per application, no later than one month prior to vine kill to assure proper tuber maturation.



Irrigation

Irrigation interval at the maximum ET is three days. Drought tolerance is moderate. Water stress can severely affect quality.



Pest control

Weeds Competes well against weeds and is not sensitive to any major herbicide. Insects Standard insect control measures generally are effective.

Fungicides Two to four fungicide applications are necessary for the control of foliar early blight.



Tuber/bulking Tuber set is moderate, medium in the hill. Tuber bulking is rapid by mid-season; resistant to blackspot, second growth, hollow heart and shatter bruise; susceptibility to growth cracks that may be associated with uneven emergence and related fertility/water stress problems.



Vine kill Average days from planting to vine kill are 1 00 to 1 1 0. Vine killing usually is required; skin set requires 1 2 to 21 days.



STORAGE MANAGEMENT



Crestone is considered a good long-term storage potato.



DISEASE REACTION



Overall disease problems are minimal. Bacterial ring rot symptom expression is intense and will occur within 90 days after planting. Potato leafroll virus symptoms usually are quite mild during the early part of the season with little or no plant color change evident. However, by mid-season symptoms are readily detected. PVY expression is mild. Virus spread is somewhat limited because of medium aphid preference.



Field

Foliar early blight Moderately Susceptible

Verticillium wilt Unknown

Blackleg Susceptible

Seedpiece decay Susceptible

Leafroll virus Susceptible

Leafroll Net necrosis Resistant

PVY Moderately Susceptible

PVX Susceptible

Common Scab Resistant

Bacterial ring rot Susceptible



Storage

Tuber early blight Moderate

Bacterial soft rot Susceptible

Fusarium dry rot Susceptible

Leak (Pythium) Unknown

Pink rot (Phytophthora) Unknown

Silver scurf Unknown

Rhizoctonia scurf Moderately Susceptible



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.