Understanding the influence of environment and correlation/relationships among
traits is necessary in selection for crop quality improvement. Therefore, correlations
among antioxidant activity (AOA), total phenolics (TP), phenolic composition, and
specific gravity (SPG) in four potato (Solanum tuberosum, L.) cultivars (Atlantic, Red
La Soda, Russet Norkotah, and Yukon Gold) grown in nine states (California, Idaho,
Michigan, Minnesota, New Jersey, North Carolina, Oregon, Texas, and Wisconsin) for
three years, and in 15 advanced selections grown in Texas were investigated. Cultivars
within and between locations were significantly different in AOA, TP, and SPG.
Significant effects of cultivar, year, location and their interactions on AOA, TP, and SPG
were observed. There were significant positive correlations among the four cultivars
between AOA and TP, and negative correlations between AOA and SPG, and between
TP and SPG. However, correlations between AOA and SPG, and between TP and SPG,
in the advanced selections were not significant.
Some tuber-bearing wild potato species were higher in AOA and TP than the
commercial cultivars; therefore, they could be used as parental material in breeding for high AOA and TP. However, use of wild species that might be higher in total
glycoalkaloids (TGA) than cultivars could result in progenies with high TGA if the traits
are positively correlated. To elucidate the relationships among AOA, TP and TGA,
accessions of Solanum jamesii and S. microdontum from the US Potato Genebank were
screened for these traits and their correlations determined. Also, anti-proliferative and
cytotoxic effects of 15 S. jamesii tuber extracts (5 and 10 μg/ml) on human prostate
(LNCaP) and colon (HT-29) cancer cells was determined in vitro.
Alpha-solanine and α-chaconine were found in both species, while tomatine and
dehydrotomatine were quantified in some S. microdontum accessions. Both species were
higher in all above traits than the Atlantic, Red La Soda, and Yukon Gold cultivars.
More than 90% of S. jamesii accessions had TGA levels < 20 mg/100g fresh weight,
while only two accessions of S. microdontum, P1 500041 and PI 473171, exhibited TGA
< 20 mg/100g. Neither AOA nor TP was significantly correlated with TGA in both
species. Also, individual phenolics were not correlated with TGA. Solanum jamesii
accessions significantly reduced proliferation of HT-29 (5 and 10μg/ml) and LNCaP
(10μg/ml) cells and were not cytotoxic compared to the control (DMSO). Therefore,
since AOA and TP were not found to be correlated with TGA, using wild accessions in
breeding for increased health promoting compounds would not necessarily increase
glycoalkaloids in newly developed potato cultivars.
| Identifer | oai:union.ndltd.org:tamu.edu/oai:repository.tamu.edu:1969.1/ETD-TAMU-3229 |
| Date | 15 May 2009 |
| Creators | Nzaramba, Magnifique Ndambe |
| Contributors | Miller Jr., J. Creighton |
| Source Sets | Texas A and M University |
| Language | en_US |
| Detected Language | English |
| Type | Book, Thesis, Electronic Dissertation, text |
| Format | electronic, application/pdf, born digital |
Page generated in 0.0705 seconds