Field evaluation of transgenic peanut lines for resistance to Sclerotinia blight and yield

Scope and method of study. Sclerotinia blight is one of the major yield reducing diseases to peanut production in Oklahoma. This study was conducted to evaluate the level of Sclerotinia blight resistance of two transgenic peanut lines. The trial was conducted near Fort Cobb Oklahoma during 2002 and 2003 using a split plot design with fungicide treatments as the main plot and genotypes as the sub plot. Sclerotinia blight incidence and yield were the traits evaluated. The two transgenic lines used were developed at the USDA-ARS laboratory in Stillwater Oklahoma. Both lines were produced by transforming Okrun with a chitinase and glucanase gene construct.; Findings and conclusions. The transgenic lines 654 had significantly less incidence of Sclerotinia blight than Okrun when subjected to high Sclerotinia blight pressure. Line 487 had less Sclerotinia blight than Okrun, but was not significantly different. At the high disease pressure created by a 0 spray treatment, both transgenic lines had higher yields than Okrun. At the 1 spray treatment, line 654 had a higher and significantly different yield to Okrun, while line 487 was not significantly different. The use of a gene construct containing a chitinase and glucanase genes has improved the level of resistance to Sclerotinia blight in two transformed Okrun lines. This gene construct may also be useful for improving the level of resistance in other peanut cultivars.