Disease symptoms often have diagnostic value. They are used also to determine the nature of the alterations in the physiology of the diseased plant, and to estimate the severity or extent of the damage caused. The search for diagnostic features is usually performed in white light. Descriptions of symptoms and conclusions as to the nature and extent of damage reflected by symptoms are usually based on the appearance of symptoms in that light. [...]

After-cooking darkening (ACD), a gray-black discoloration, is one of the key quality defects of the potato. Previous work using a diploid population 13610 identified 14 single nucleotide polymorphism (SNP) markers, located on eight chromosomes, which have the strongest association with ACD. Seven of these markers are located in four major quantitative trait loci (QTL) on chromosomes 2, 4, 6, and 10. It is hypothesized that these 14 markers would also have significant relationship to ACD in other breeding populations. Therefore, their effects in another diploid population 14946 were analyzed by amplicon genotyping using high-resolution DNA melting (HRM). Eleven of the 14 SNP markers were confirmed to be significantly associated with ACD. Six of the 11 markers were located in the four major QTL regions. In addition, unlabelled probe assays using HRM were performed on a group of clones in the tetraploid population 14945. Five from the 14 markers were analyzed, and three showed significant relationship to ACD. The methodology established and the markers identified in this study could benefit breeding programs for developing lower ACD varieties.

No description available.

The potential of different spectroscopic techniques for evaluating potato (Solanum tuberosum L.) quality was investigated. Spectral data in the wavelength range of 400-1750 nm were used to develop quality prediction models. The Partial Least Squares (PLS) regression was used for predicting the water content in potato samples. Water content was predicted with R2 ≥ 0.938. / A further study was conducted to find the best wavelengths for predicting water content using two methods, PLS and multiple linear regression. Wavelength ranges of 910-1020, 1129-1211, 1363-1403 nm were selected for samples without skin, while 700-900, 930-1050, 1100-1300, 1400-1550 nm were selected for samples with-skin. Weight prediction models were established using the predicted water content. / Visible spectroscopy was used for classifying shriveled and non-shriveled potatoes. The wavelength ranges best suited to such a classification were those of 442-452, 456-466, 641-651, and 684-694 nm, with accuracies as high as 94.28% and as low as 80%.

Graduation date: 1930

Graduation date: 1956

Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1994. / Vita. Abstract. Includes bibliographical references (leaves 73-81). Also available via the Internet.

Thesis (M.S.) in Plant, Soil and Environmental Sciences--University of Maine, 2003. / Includes vita. Includes bibliographical references (leaves 79-84).

Thesis (Ph. D.)--University of Wisconsin--Madison, 1940. / Typescript. Includes abstract and vita. eContent provider-neutral record in process. Description based on print version record. Bibliography: leaves 67-69.

Thesis (Ph. D.)--Clark University, 1987. / Typewritten manuscript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 351-370).