The Effect of Three Digging Dates on Oil Quality, Yield, and Grade of Five Peanut Genotypes Grown Without Leafspot Control1

Abstract

Abstract Five peanut (Arachis hypogaea L.) genotypes, Southern Runner, Dixie Runner, Florunner, UF82206, and UF714021, were grown for three years, 1982–1984, near Gainesville, Florida without fungicide applications. Three digging dates, averaging 105 days after planting (DAP), 118 DAP, and 132 DAP, were used each year to determine the effects of early harvest as a management practice for peanut production under leafspot pressure. The different digging dates had no effect on fatty acid composition of the five genotypes, and had only minimal effect on the oil content and iodine value. The largest oil quality differences in this study were due to differences among genotypes and year-to-year variation. The earliest digging date tended to reduce market grade characters, but major pod yield differences were the result of genotype × digging date interactions. Genotypes with little or no resistance to leafspot diseases, such as Florunner and UF 714021, produced nearly 3000 kg/ha without leafspot control up to 118 DAP and then had sharp yield decreases, while resistant genotypes such as Southern Runner and UF 82206 continued to produce pod yields of 3000 kg/ha or higher up to 132 DAP.