Hugh J. Murphy

Atlantic: A new potato variety with high solids, good processing quality, and resistance to pests

Atlantic is a medium late maturing var. which has been shown to have the following characteristics: tolerance to scab and Verticillium wilt; high yields of attractive tubers; resistance to the bacterial disease pink eye; high solids content; excellent chip and French fry quality and acceptable fresh market quality. It is low in total glycoalkaloids. It was evaluated for yield, sp. gr., and chipping quality from 1973 through 1975 in replicated trials with locally adapted var. Compared with locally adapted var. grown in Florida, Virginia, New Jersey and Maine, Atlantic excelled in TS content. It contained 24.4% more TS than Sebago in Florida, 14.8% more than Pungo in Virginia, 14.9% more than Superior in New Jersey and 18.1% more than Superior and Katahdin in Maine. Mean chip colour scores were better for Atlantic than for locally adapted var. grown in Florida, New Jersey, and Maine. It produced excellent chips when either processed within 2 wk of harvest and then held at ambient air temp. for 6 wk or held in 4°C temp. storage and then reconditioned at 21°C for 14 days. The baking quality of Atlantic was rated acceptable.

Effects of differential rates of nitrogen and phosphorus on early blight in potatoes

The Kennebec variety of potato was exposed toAlternana solani inoculum during the 1970 and 1971 seasons to determine the effects of differential rates of nitrogen and phosphorus on the incidence of early blight. Both high nitrogen and low phosphorus treatments significantly reduced the incidence of early blight and the combination of high nitrogen and low phosphorus consistently gave the lowest incidence of the disease during both years. The data suggest that this combination of nutrients may be related to early blight resistance in the plant by extending the period of meristematic activity permitting the plant to wall off infection. Yield data indicated that there was too great a yield difference between fertilization for optimum early blight control and fertilization for optimum yield. Therefore, in Maine, potatoes should be fertilized for optimum yield with a reasonable specific gravity, and early blight should be controlled by the application of fungicides and sanitation measures.

The effect of crop rotations on Rhizoctonia disease of potatoes

Since 1964, replicated rotation plots in Presque Isle, Maine have continually been planted and evaluated to determine the effect of various rotation crops on tuber appearance, quality, and yield. In 1974 and 1975, the saprophytic activity ofRhizoctonia solani in the soils of each rotation combination was determined, and the tubers harvested were scored forRhizoctonia damage. Soils with a two-year rotation of oat-potato had the lowest amount of saprophytic activity byRhizoctonia and provided the lowest incidence of disease on the stems, roots, and tubers of the cultivars Kennebec and Katahdin. With the cultivar Russet Burbank, the three-year rotations generally provided the lowest incidence of disease; however, this cultivar is more susceptible to the pathogen. The plots of potatoes that were not rotated had the highest pathogen activity and the greatest disease incidence.ResumenDesde 1964 parcelas replicadas de rotación en Isla Presque, Maine, han sido continuamente sembradas y evaluadas para determinar el efecto de varias rotaciones de cultivo en la apariencia, calidad y rendimiento de papas. En 1974 y 1975, la actividad saprofítica deRhizoctonia solani en los suelos de cada combinación fue determinada, y los tubérculos cosechados fueron evaluados para dano porRhizoctonia. Suelos con dos anos de rotación de cebada-papa tuvieron la más baja cantidad de actividad saprofítica deRhizoctonia y dieron la más baja incidencia de la enfermedad en los tallos, raíces y tubérculos de los cultivares Katahdin y Kennebec. Con el cultivar Russet Burbank, la rotación de tres años generalmente dió la incidencia más baja de la enfermedad; sin embargo, este cultivar es más susceptible al patógeno. Las parcelas sin rotación tuvieron la actividad más alta del patógeno y la mayor incidencia de la enfermedad.

Abnaki: A new high-yielding potato variety resistant to verticillium wilt and leaf roll

Abnaki, a new potato variety, was released February 18, 1971, by the Plant Science Research Division of the United States Department of Agriculture, the Maine Agricultural Experiment Station, and the New York Agricultural Experiment Station. Abnaki, tested under the pedigree number B5415-6, was selected from a crose between U S D A seedling X1276-185 and B4116-2. Approximately 380 seedlings from this cross were grown from true seed in the greenhouse at Beltsville, Maryland in 1961. Abnaki was one of 20 saved from single-hill selections from the 1962 increase in Maine.

Chemical composition of potatoes. III. Relationships between specific gravity and the nitrogenous constituents

SummaryKatahdin potatoes from Maine (1960 crop) were separated into high, intermediate, and low specific gravity levels immediately after harvest, then stored in the cold. Samples were withdrawn periodically for analysis. Concurrently, New York grown Katahdms were placed in cold storage and samples, when withdrawn for analysis, were separated into three specific gravity levels. The pre-separated Maine potatoes permitted more refined analytical data to be compiled. There was a progressive loss of weight during storage which was greatest in potatoes with the lowest solids content. Specific gravity changed very little during storage. The shrinkage therefore is due to a loss of solids and moisture in the ratio of the original composition. With only minor differences in the 1959 and 1960 growing seasons in Maine, there were marked differences in the composition of potatoes grown during these two seasons.

Effect of tetrachloronitrobenzene (fusarex) on emergence and yield of potatoes. Part III. — Northeast

SummarySeed potatoes of the Katahdin, Kennebec, and Pungo varieties were treated with Fusarex dust containing 6% tetrachloronitrobenzene at three dates in Maine during 1961–62 storage season. In 1962, these chemically treated seed potatoes were planted in uniform tests and compared with seed stocks that had been desprouted once and also with untreated seed tubers. Cooperators in Maine, Long Island, and New Jersey, Pennsylvania, and New Brunswick, Canada recorded plant emergence and yield data at each location.Treatment of seed potatoes with Fusarex delayed initial plant emergence of all varieties at all locations except in Maine and Canada where Fusarex treatment increased emergence of the Pungo variety as compared to untreated seed. Total emergence varied by variety and location.Date of seed treatment with Fusarex did not affect emergence significantly. Emergence of desprouted seed tubers was not significantly lower than untreated or chemically treated seed at most locations.Treatment of seed with Fusarex decreased yields of tubers in Pennsylvania and on Long Island. At all other locations yields were slightly better when seed had been treated with Fusarex. No significant statistical differences in yields occurred between treatments at any of the five test locations when varieties and locations were aceraged.ResumenSemillas de papas de las variedades Katahdin, Kennebec y Pungo fueron tratadas en tres diferentes fechas con polvo “Fusarex” al 6% del producto ativo, tetraclorobenceno, durante la estación de almacenamiento. (1961–62) en Maine.En 1962, las semillas fueron plantadas en pruebas uniformes y comparadas e ntre las que recebieron tratamiento quimico. Las que no recebieron y entre semillas almacenadas que tenian sido deshijadas una vez. Cooperativistas en Maine, Long Island, New Jersey, Pennsylvania y New Brunswick, Canada, reuniron dados sobre la germinación y rendimiento de las plantas en cada localidad.El tratamiento de las semillas con “Fusarex” retardó la germinación de todas las variedades, y en todas las localidades, excepto en Maine y en Canada. En donde el tratamiento con “Fusarex” estimuló de germinación de la variedad Pungo, cuando esta fué comparada con semillas no tratadas. Las fechas de los tratamientos de las semillas con “Fusarex” no afectaron significativamente la germinación.En la mayoria de las localidades la germinación de las semillas deshijadas no fué significativamente más baja que la de las semillas no tratadas, o en las tratadas quimicamente.El tratamiento quimico de las semillas con “Fusarex” reducció la cosecha en Pennsylvania y en Long Island.En todas las otras localidades las cosechas fueron ligeramente superiores, cuando las semillas habian sido tratadas con “Fusarex.” En minguna de las localidades, las cosechas obtenidas en los diferentes tratamientos estudiados, fueroo estadisticamente siguificativos, cuando variedades y localidades fueron comparadas.

Effect of physiological maturity and storage temperature on emergence and yield of potatoes

SummaryA three-year study was conducted at Presque Isle, Maine to determine the effects of maturity and storage temperature on the yield and emergence of Katahdin seed potatoes. Virus X, place-effect, and variations in cultural practices were not confounding factors in these studies.Variations in maturity of the seed stocks compared did not show any significant differences in plant emergence or yielding ability of progeny produced. When the variables of virus X, place-effect, storage temperature, and growing practices were eliminated as confounding factors, there was no effect on productiveness of progeny produced from seed stocks varying in maturity.Storage temperatures affected emergence rate of seed potatoes and their yielding ability. From the results of this study, seed stored at 38F was more productive than seed stored at 32F or 45F.ResumenEn Presque Isle, Maine, se llevó a cabo un estudio de tres años para determinar los efectos causados por temperaturas de almacenaje y madurez en el rendimiento y emergencia de semillas de papa Katahdin. Virus x, efecto de colocación, y diferencias en practicas de cultivo fueron factores que no interfirieron con el estudio.Con variaciones en la madurez de las semillas comparadas, no se observó ninguna diferencia significativa en la emergencia de las plantas o en la capacidad de rendimiento de la progenie producida. Cuando las variantes de virus x, efecto de colocación, temperatura de almacenaje, y prácticas de cultivo fueron eliminadas como factores interfirientes, la madurez de la semilla tampoco afectó la productividad de la progenia producida.La habilidad de rendimiento y la emergencia inicial de las semillas de papa fueron afectadas por las temperaturas de almacenaje. De los resultados obtenidos en este estudio, las semillas almacenadas a 38F fueron más productivas que las almacenadas a 32F o a 45F.

Delta Gold: a new potato variety with yellow flesh, high solids and high quality for baking and processing.

Delta Gold is a medium-late maturing, round, yellowish-skinned, yellow-fleshed variety which is excellent for baking and processing. Its yields have been lower than Kennebec; however, specific gravities have been higher. It is moderately resistant to scab and early blight and immune to net necrosis and virus A.ResumenDelta Gold es una variedad de maduración semi tardía, con tubérculos redondos, de piel amarillenta y de carne amarilla, excelentes para horneado y procesamiento.A pesar que sus rendimientos han sido menores que los de Kennebec, su gravedad específica ha sido mayor. Es moderadamente resistente a la sarna y al tizón temprano e inmune a la necrosis en red y al virus A.

Campbell 14: A verticillium resistant round white potato variety

The Campbell 14 potato variety is a medium-late maturing variety with round to oblong, smooth, shallow-eyed, white tubers. This variety is intended primarily for fresh market; however, under some conditions chip color will be acceptable. Campbell 14 is resistant to verticillium wilt and to the net necrosis caused by the potato leafroll virus.ResumenLa variedad de papa Campbell 14 es una variedad de maduración medianamente tardia, con tubérculos blancos, entre redondos y oblongos, lisos y de ojos superficiales. Esta variedad es fundamentalmente destinada a ser comercializada sin procesar; sin embargo, bajo ciertas condiciones, el color que toma en la forma de hojuelas es normalmente aceptable. Campbell 14 es resistente a la marchitez por Verticillium y a la necrosis reticular causada por el virus del enrollamiento de las hojas de papa.

Abstracts of papers presented at the Fifty-Second Annual Meeting of The Potato Association of America

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