Author: Wilford M. HessPublisher:
ISBN:
Category : Onions
Languages : en
Pages : 144
Book Description
Pink Root of Onion Caused by Pyrenochaeta Terrestris
Author: Wilford M. HessPublisher:
ISBN:
Category : Onions
Languages : en
Pages : 144
Book Description
A Study of the Pink-root Disease of Onion
Author: August Mark GorenzPublisher:
ISBN:
Category : Onions
Languages : en
Pages : 168
Book Description
Effect of Pyrenochaeta Terrestris on Pink Root Disease Severity and Plant Growth of Short Day Onions
Author: Sam Victor OrnelasPublisher:
ISBN:
Category : Onions
Languages : en
Pages : 128
Book Description
The Effect of Pink Root, Caused by Phoma Terrestris Hansen, on Yield of Onion (Allium Cepa L.)
Author: Pamela Marie ColemanPublisher:
ISBN:
Category : Fungal diseases of plants
Languages : en
Pages : 272
Book Description
Procedures for Evaluation of Onion Varietal Resistance to the Pink Root Fungus Pyrenochaeta Terrestris and Exudate Produced by this Fungus
Author: W. M. HessFactors Influencing the Development of Onion Pink Root Disease Incited by Pyrenochaeta Terrestris (Hansen) Gorenz, Walker, Larson
Author: Paul Eugene PackPublisher:
ISBN:
Category : Onions
Languages : en
Pages : 184
Book Description
A study was conducted of the influence of various climatic and soil factors on the development of onion pink root disease and of the influences of temperature, light, pH, carbon and nitrogen sources, and vitamins on the growth in vitro of an Oregon isolate of the pink root fungus, Pyrenochaeta terrestris (Hansen) Gorenz, Walker, Larson. Eleven onion lines were planted in eastern and western Oregon to determine whether the relative resistance to pink root among them would vary during the growing season and with different climatic conditions. Varietal resistance remained generally stable among the different lines. Ten onion lines were grown in mucky peat and silty clay loam soils in the greenhouse to determine the influence of soil moisture and soil type on severity of pink root. Onions grown in soil held at field capacity had less pink root than those in dryer soils. Pink root ratings were similar among onions grown in both soils. Lanstan, Vorlex, Telone, Pictel, Morton Soil Drench, SD 345, chloropicrin, Mumfume, Phaltan, E.P. 230, and E.P. 201 were tested in the field for their effect on pink root. In some fields Vorlex, chloropicrin, Mumfume, E.P. 230, and E.P. 201 increased onion yields from 30 to 75 percent. None of these fumigants noticeably reduced pink root, however. Telone controlled stubby root nematode infection but did not reduce pink root. On malt extract-yeast extract agar P. terrestris grew fastest at a temperature of 30 C, with the greatest increase in growth rate between 15 and 20 C. There was no growth at 5 C. Continuous light, alternating darkness and light, and brief exposures to germicidal ultraviolet light (2,500 A[superscript °]) did not noticeably affect the growth rate of the fungus. Growth of P. terrestris increased the pH of glucose-asparagine and sucrose-potassium nitrate liquid media. On both media the fungus grew well over a pH range from 6 to above 8 but poorly at a pH of 4 or less. Sorbose inhibited growth of P. terrestris. Maltose, galactose, glucose, fructose, sucrose, lactose, and starch in asparagine liquid and agar media each supported good growth of the fungus, as did glycine, potassium nitrate, and urea in glucose agar. The addition of thiamine, biotin, inositol and pyridoxine to sucrose -asparagine agar did not noticeably affect P. terrestris growth. Higher temperatures coincided with greater pink root infection in the field.
Influence of Different Hosts on Populations of the Onion Pink Root Pathogen, Pyrenochaeta Terrestris
Author: Weili MaoPublisher:
ISBN:
Category : Host plants
Languages : en
Pages : 118
Book Description
Resistance Mechanisms Against Onion Pink Root (Pyrenochaeta Terrestris), Bioassay of Inoculum Potential in Soil and Chemical Control
Author: Sidney R. SiemerPublisher:
ISBN:
Category : Onions
Languages : en
Pages : 272
Book Description
Pink Root Disease of Onions and Its Control in Texas
Author: Jacob Joseph TaubenhausPublisher:
ISBN:
Category : Agriculture
Languages : en
Pages : 58
Book Description
Screening Technique for Onion Pink Root (Pyrenochaeta Terrestris (Hans) Gorenz, Walker and Larson.) Resistance
Author: Jaime Iglesias-OlivasPublisher:
ISBN:
Category : Onions
Languages : en
Pages : 120
Book Description