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Full-Text Articles in Agriculture
The Influence Of Various Soil Factors Upon Potato Scab Caused By Actinomyces Scabies, R. W. Goss
The Influence Of Various Soil Factors Upon Potato Scab Caused By Actinomyces Scabies, R. W. Goss
Historical Research Bulletins of the Nebraska Agricultural Experiment Station
Scab, caused by Actinomyces scabies (Thaxt.) Giiss., is a potato disease of major importance in western Nebraska. Seed treatments are effective in controlling seed-borne scab, but it has been shown that even when healthy or treated seed potatoes are used the disease may be very severe because of infection from the soil. Crop rotation will reduce the incidence of the disease, but the fact that potato scab may cause serious loss in soils never before planted to potatoes indicates that there are numerous factors other than the time interval between potato crops which affect the occurrence of the disease. A …
A Study Of The Environmental Conditions Influencing The Development Of Stem Rust In The Absence Of An Alternate Host. Iii. Further Studies Of The Viability Of Urediniospores Of Puccinia Graminis Tritici, George L. Peltier
Historical Research Bulletins of the Nebraska Agricultural Experiment Station
1. The influence of relative humidity and temperature on the viability of the urediniospores of two Physiologic Forms of Puccinia graminis tritici has been determined. 2. The same general relation between the viability of the urediniospores and the relative humidity and temperature was found, namely, that the lower the temperature the longer the spores retained their viability at all relative humidities, while at any stated temperature the spores were viable the longest at the medium humidities. 3. Urediniospores of Physiologic Form XXI held at 49.0 per cent relative humidity and maintained at a temperature of 5° C. when tested for …
Effect Of Environment On Potato Degeneration Diseases, R. W. Goss
Effect Of Environment On Potato Degeneration Diseases, R. W. Goss
Historical Research Bulletins of the Nebraska Agricultural Experiment Station
During recent years much of the investigational work on the degeneration diseases of the potato has been directed toward the separation and identification of a number of diseases formerly grouped under the general names of mosaic, leaf roll, and "running out". Extensive studies have also been made on methods of transmission, host range, overwintering and the identification of the evasive causal factor. Investigations of this type, however, have progressed slowly because of the necessity of developing new methods of research, because of the complexity of the problem, and because of the lack of knowledge regarding the causal factors. Meanwhile there …
A Study Of The Environmental Conditions Influencing The Development Of Stem Rust In The Absence Of An Alternate Host. Ii. Infection Studies With Puccinia Graminis Tritici Form Iii And Form Ix, George L. Peltier
Historical Research Bulletins of the Nebraska Agricultural Experiment Station
Stakman and Levine have shown that Puccinia graminis tritici (Pers.) Erikss. and Henn. consists of a number of biologic forms, which can be determined by their action on different varieties of Triticum species. To date 37 such biologic forms have been identified by them through the parasitic action on 12 differential hosts chosen from a large number of varieties of Triticum species. To determine whether these biologic forms remain constant in their behavior under various environmental conditions, a detailed study of the host-parasite relation was undertaken with 2 of these forms. At the same time an opportunity was afforded to …
A Study Of The Environmental Conditions Influencing The Development Of Stem Rust In The Absence Of An Alternate Host. I. The Viability Of The Urediniospores Of Puccinia Graminis Tritici Form Iii, George L. Peltier
Historical Research Bulletins of the Nebraska Agricultural Experiment Station
No exact data are at hand regarding the influence of temperature and relative humidity on the viability of the urediniospores of stem rust under controlled conditions. 1. The influence of relative humidity on the viability of the urediniospores of Puccinia graminis tritici Form III is very pronounced and closely associated with temperature. 2. At high relative humidities, depending somewhat on the temperature, the percentage of germination is low and the period over which the spores are viable is very short. 3. The same relation exists at the low relative humidities except that it is not so pronounced and is more …