H. O. Werner

Relative response of several varieties of potatoes to progressively changing temperatures and photoperiods controlled to simulate “northern” and “southern” conditions

SummaryFor the purpose of determining adaptability and nature of response of varieties when grown in widely differing latitudes, two strains of Triumph potatoes and five other varieties were grown in the greenhouse under day length and temperature conditions simulating those that occur in the gulf coast (“southern”) and those occurring in northwestern Nebraska (“northern”). Potatoes were harvested at intervals to determine the morphological development throughout the life period.With all potato varieties tested under “northern conditions” in contrast with “southern conditions” maximum vegetative growth was greater and continued later into the season, stolon growth was much more extensive, tubers developed later and in greater numbers with greater total weight, but ratios of weight of tubers to that of the tops were lower.The early varieties were able to develop larger vines and more tuber weight early in the season under northern conditions while days were still hot and long than could the late varieties which responded better to the cool short days late in the season.The “northern” type of environment permits the manifestation of more varietal differences than does the “southern” type.When judging tuberization efficiency by ratios of green weights of tubers to tops, the early varieties appeared more efficient than the late ones under both conditions.Stolon growth and numbers of tubers set were increased to a very much greater extent under northern than under southern conditions with the Triumph than with any other variety.

Performance of clonal strains of triumph potatoes

ConclusionEven though differences in strains vary a great deal from year to year, there seem to be a few important consistent differences.Under the conditions at Alliance with dry land culture, yields have been greatest with the later strains in all years except the very dry or drought years. Early types have produced the smoothest best type tubers that generally cracked slightly less at harvest time. Early strains almost always yielded more No. 2 size tubers, but the late strains generally produced the greatest number No. 3 size tubers.Apparently the earliest and latest are not the most desirable strains. The midseason strains seemed the most suitable for tuber production under the range of conditions that occurred. During the ten years of these tests climatic conditions varied from one extreme to another as much as they have varied during the last 50 years.

Effect on berry production of varied day length during the life of two triumph potato strains

SummaryWith an intermediate strain of Triumph potatoes (Triumph 22), the continual use of long photoperiods until pollination time resulted in the most berries.When long photoperiods were used during relatively short intervals in the life of the plants, they appeared to be most useful when the flowers were making their final development.Long photoperiods very early in the life of the plant were very useful for berry production, but were not indispensable and unless the long photoperiods were continued for 60 or 70 days they brought about the production of relatively few’ berries.Berry production occurred with an 18-hour photoperiod, but production was only one-third as great as with a 24-hour photoperiod.No berries were developed by the very early strain (Triumph 12) with an 18-hour photoperiod and with this strain berries were produced with only four of the 24-hour photoperiod treatments.Our evidence indicates that induction of flowering in Triumph potatoes by using long photoperiods for short intervals of time is not feasible and except under very favorable conditions of high light intensity it is not possible.

Flower and berry production by potatoes as influenced by two light intensities and two midwinter planting dates

ConclusionsWith an eighteen-hour day, flower and berry production were improved in midwinter by increasing the intensity of the light. This was accomplished by either increasing the intensity of the supplemental light or by planting later so that the plants obtained the benefit of the brighter, longer days. An increase in the average daily radiation from 226 to 254 gm. cal. per sq. cm. seemed as effective in stimulating flowering and berry production with some varieties as increasing supplemental light from about 35 to about 115-foot candles. With some varieties increased daylight intensity was more beneficial than increasing the supplemental light.Nine varieties which bloomed in April, 1937, were not induced to bloom by any of the treatments used in this experiment.

Performance of clonal strains of triumph potatoes II. Comparison of strains under irrigation conditions in Western Nebraska

and a smaller yield of tubers than Seedlings 2135, 47053, and 2134, but much less vine injury than Rural New Yorker, Triumph and Earlaine. In previous tests at Greeley, Katahdin, Rural New Yorker and Triumph gav e results similar to those for the years 1938 and I939 . Of the hundreds of seedlings that have been tested for fusarium resistance, some have been more susceptible than the Rural New Yorker and Triumph, whereas many others have shown some tolerance. Although Seedling 2135 has shown only slight vine symptoms of fusarium and produced good yields of tubers, this seedling cannot be introduced for commercial p!antings because the flesh is tinged with red, a very objectionable feature in a commercial variety. Seedling IiO, which may soon be introduced, has a record similar to that of Katahdin. Figure I shows a photograph of one plot of this seedling taken on the 25th of August, 1939 . The vines show considerable vigor, whereas the vines of some of the more susceptible seedlings have been killed. These tests indicate that it may be possible to develop commercial varieties of potatoes with a high degree of resistance to fusarium in the field.

The significance of pre-emergence soil moisture to yield of potatoes on dry land in the western high plains area

ConclusionsIn the high plains area in western Nebraska precipitation, occurring prior to planting time, or at least prior to emergence, of main season plantings of potatoes has been a more significant factor in the production of satisfactory yields than the rainfall during the crop season. Very satisfactory yields of potatoes have been produced with only the moisture stored in the soil prior to the emergence of the potato plants. In years of low rainfall the potato crops have practically been failures when planted after small grain, because of the serious depletion of soil moisture as deep as the fifth foot. Potato yields following corn have been fairly good since this crop removed very little mois ture below the third foot. The best potato yields have been obtained following summer fallow. During summers of little rainfall, the potatoes removed practically all available moisture from the upper five feet of soil.

Is there any difference in the productivity of dry land and irrigated seed potatoes

ConclusionThese trials and others made throughout the last fifteen years as well as extensive observation of a number of lots of seed under a variety of conditions seem to warrant the conclusion that production under irrigation does not impair the seed value of seed stocks that are free from virous diseases.

Cultivating potatoes under western conditions

Considering tubers of marketable size (above 50 grams), the dry matter percentage in the tubers grown at p H 5.64-6.05, is higher, in most cases, than in tubers grown at the higher or lower soil reactions. The starch percentage, on the fresh basis, of the marketable tubers when grown in soil p H 7.16-7.45 was lower than that of tubers grown in the more acid soils. In general, the starch percentage of tubers grown at a.soil reaction of p i t 5.64-6.05 is higher than that of tubers grown at either the higher or lower pI-I range. Any differences in starch and d ry mat ter content of potato tubers may also affect their cooking quality. Mealiness of potatoes, when cooked, is due par t ly to the content of stareh and moisture or the ratio between the two. Excessive mealiness often is undesirable in potatoes cooked by boiling because of the sloughing off of the outer layers resulting in the potato falling apart. Pre l iminary boiling tests indicate that immature tubers and tubers grown at a reaction of p i t 7.167.45 are less objectionable on this point than mature tubers or those grown at a reaction of pH 5.64-6.05. In these experiments a relationship is indicated between better table quali ty of potatoes for boiling and a somewhat lower percentage of starch as: brought about by immature harvesting or growth at soil reactions of ra ther high pH.

Platte and Hi-Plains, two new scab resistant processing potato varieties

SummaryPlatte is a high yielding, medium to late maturing variety, with round white tubers of medium to high specific gravity. Good chips may be made from this variety before storage and from reconstituted potatoes after 38 to 40 F storage. It is resistant to common scab and Fusarium wilt and tolerant to Verticillium wilt.Hi Plains is a medium to medium-late maturing variety producing moderately high yields of long, white tubers of intermediate specific gravity. Its tubers boil, bake, chip and french fry well. Hi Plains is moderately resistant to common scab and tolerant to Fusarium wilt but susceptible to Verticillium wilt.Under conditions of high temperatures or stress for soil moisture, Platte produces small tubers in chains, and Hi Plains produces rough and irregularly shaped tubers. In trials in the North Central States, Hi Plains was comparable to Irish Cobbler in yield of U.S. ‡1 potatoes and dry matter content. Platte produced high yields of U.S. ‡1 potatoes of intermediate dry matter content. Platte was adapted to the northern fall-crop states, whereas Hi Plains was more widely adapted.Sumario En EspañolPlatte es una variedad de papa de alto rendimiento, mediana o tardiá maduración, con tubérculo de forma redondeado, blanco y de mediano a alto peso específico. Con es ta variedad se hacen buenas papas a la inglesa antes de estar almacenadas y después de reconstituitarse en sequida de almacenaje a 38–40 F. Resistente a loStreptomyces scabies, marchitezFusarium sp. y tolerante aVerticillium albo-atrum.Hi Plains es una variedad de papa de mediana o tardiá maduración con rendimiento moderamente alto de tubérculo grande, blanco de mediano peso especifico. Los tubérculos, se cuecen, hornean, don buenas papas a la inglesa y frien bien. Hi Plains es moderadamente resistente a la Streptomyces scabies, tolerante a marchitezFusarium sp. pero susceptible aVerticillium albo-atrum.En condiciones de elevada temperatura o déficit de humedad en el suelo, Platte produce tubérculos pequeños en cadena y Hi Plains produce tubérculos rugosos e irregulares en forma. En experimentos relizados en los estados del centro norte. Hi Plains fué comparable a Irish Cobbler en producción de papas grado U.S. ‡1 y contenido de materia seca. Platte produjo alto rendimiento en papas grado U.S. ‡1 con contenido intermedio de materia seca. La variedead Platte se adaptó mejor, a los estados del norte con producción de otoño, en tanto que Hi Plains presentó una adaptación más amplia.

Potato planting rates with dryland culture in Western Nebraska

Summary1.Three varieties of potatoes were grown on dryland in Western Nebraska for 3 and 7 years with three planting rates using combinations of two seed piece sizes at two planting distance.2.An intermediate planting rate (approximately 12 bushels per acre) appeared the most practical because of the highest yields, especially the highest net yields of marketable potatoes. This appears to be the most practical rate for most dryland production.3.With the intermediate planting rate, close planting of small seed pieces was much more desirable than twice the distance with seed pieces weighing twice as much.4.With planting rates of 23.5 bushels per acre total yields were only slightly greater than with the intermediate rate attained by close planting of small seed pieces, but tubers were usually smaller.5.The heaviest planting rate (23.5 bushels per acre) was found to be desirable for producing greatest total yields and greatest yields of seed-size potatoes (U. S. #1-small and B size tubers), but least efficient in production per bushel of seed planted. Increased returns for the additional bushels planted (beyond those required for the intermediate rate) were relatively small, indicating that the heavy rates are not likely to be economical except when seed potatoes are very cheap.6.The lowest planting rate (approximately 6 bushels per acre) produced the greatest yield per bushel of seed planted and the largest tubers, but yields per acre were too low to merit consideration of this rate except when very high-priced seed potatoes or stocks of new or superior strains or varieties are to be increased as rapidly as possible.