| The objective of this study was to develop peanut cultivars with improved levels of resistance to Sclerotinia blight, Oklahoma’s major disease-based cause of reduced peanut yields. The researchers contend that while some varieties, such as Southwest Runner and Tamspan 90, have developed good levels of resistance to Sclerotinia, the bar needed to be raised higher.
During 2001 and 2002, several transgenic lines developed by the USDA for improved Sclerotinia resistance were field tested at Ft. Cobb, Ok., and confirmed to have higher levels of resistance than Okrun, the line on which they were originally based. In this experiment, the backcross breeding procedure was used. The transgenic parents were confirmed to have relatively stable inheritance of higher levels of Sclerotinia resistance, while the recurrent parents were selected for their good agronomic performance and for their high oleic acid trait.
Fifty-six potential F1 seeds were harvested during 2002, but only two of the F1 plants were confirmed to have the gene(s) for Sclerotinia resistance. The F2 seeds were harvested for further testing during 2004. As of the time of this report, additional crosses for potential F1 plants had been made and were being grown in the research facility greenhouse.
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