Susceptibility of virginia- and runner-type peanuts to common diseases of peanut in Virginia, 2008

摘要

The field site was Goldsboro fine sandy loam with a history of moderate to severe crop damage by CBR and northern root-knot nematode. Wheat/soybean and peanut were grown in alternating years at the site since 1995. Main plots were treated with and without Vapam and subplots were planted to cultivars of either virginia- or runner-type peanuts. Treatments were applied in twelve, 35-ft rows spaced 3-ft apart in four randomized complete blocks. Vapam 42% at 7.5 gal/A was applied 8-in. under each row witha coulter and trailing chisel shank on 14 Apr. Disks and a bed shaper produced smooth beds measuring 24-in. wide and 4-in. high over the treated rows. In-furrow treatments of Temik 15G at 7 lb/A wereapplied at planting to the seed furrow on 1 May. Subplots consisted of two-row plots of six virginia-type cultivars and six runner-type cultivars. A broadcast spray of Orthene 97S at 8 oz/A was applied on 19 May and 3 Jun for thrips control, andLorsban 15G at 13 lb/A was applied in a 12-in. band over rows during cultivation on 19 Jun for control of southern corn rootworm. The trial was not irrigated. Recommended management practices were followed for weed control and nutrient management throughout the season. Leaf spot diseases were controlled by sprays of Folicur 3.6F at 7.2 fl oz/A with Induce (0.125% v/v) on 17 Jul, Provost at 9 fl oz/A on 12 Aug, and Headline 250EC at 9 fl oz/A on 9 Sep according to the Virginia Peanut Leaf Spot Advisory Program. Omega 500 was applied at 1 pt/A on 12 Aug with the Provost application for management of Sclerotinia blight. Peanuts were inverted into windrows on 6 Oct and harvested with a two-row combine on14 Oct. Yield was determined after drying and adjusting the weight of whole pods to 7% moisture. A composite sample of pods from four replications of each cultivar was graded by Federal-State Inspection Service methods to determine market value of yield.