Improving Grade Attributes in Disease Resistant Texas Peanut Breeding Lines using a Typical Pedigree Selection Technique.

The Texas A&M peanut breeding program has been developing peanut breeding lines and cultivars with resistance to Tomato spotted wilt virus, Sclerotinia blight caused by Sclerotinia minor Jagger, and other peanut diseases for three decades. The program has released four runner cultivars, ‘Tamrun 96’, ‘Tamrun OL 01’, ‘Tamrun OL 02’, and ‘Tamrun OL07’ with disease resistance over the past twelve years.  Release data on each of these cultivars typically reveal no statistical difference between the grades of these releases and commercial cultivars such as Flavor Runner 458 which have no disease resistance packages.  However, numerically our disease resistant cultivars grade 1% to 2% lower than Flavor Runner 458 in our field trials.  Crosses were made in 2003 between our multiple disease resistant breeding lines and ‘Tamrun 98’ a previous Texas release that has grade potential equal to that of the highest grading commercial cultivars in an attempt to improve the grade attributes of our multiple disease resistant breeding lines.  A pedigree selection was applied in the F₃ generation and individual selections were increased and then shelled out and measured for grade characteristics.  Initially, a single yield test was conducted in 2006 from which yields and grades were analyzed to determine final selections.  These selections were evaluated in replicated yield tests at five locations during the 2007 growing season.  Preliminary data from 2007 indicates that several selections from these crosses are equal to Flavor Runner 458 for grades (p≤ 0.05) and four of these lines Tx055305, Tx055306, Tx055307, and Tx055308 had higher grades than the disease resistant checks Tamrun OL 01, Tamrun OL 02, and Tamrun OL07 (p≤ 0.05).