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

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.

Mechanical Properties and Chemical Composition of Peanuts as Affected by Harvest Date and Maturity

“…Peanuts harvested at 155 DAP had slightly lower oil content (48.2%) than those harvested at 125 DAP (50.8%). Rnauft et al (1986) reported that oil contents of Florunner peanuts harvested at 105 and 132 d were 48.9 and 46.7%, respectively (dry basis), comparable to the results of this study. Carbohydrates content decreased from 27.4% at 110 DAP to 25.1% at 115 DAP.…”

The Influence of Planting and Digging Dates on Yield, Value, and Grade of Four Virginia-type Peanut Cultivars1

“…Knauft et al (2), also using one planting date and five genotypes harvested at three dates (105,118, and 132 days after planting), found that earlier digging dates tended to reduce market grade characters. In their study without leafspot control, major yield differences were the result ofgenotype x digging date interactions.…”

Relations Between Leaf Area Index and Growth Characteristics of Florunner, Southern Runner, and Sunrunner Peanut1

“…Many pods remained in the soil when plant were dug and inverted at this time, so the decline may be due to pod loss. This corresponds with the observation by Knauft et al (16) where Florunner lost more than halfits pod yield when harvested at 132 versus 118 DAP. In their study, however, fungicides were not used to control the leafpot epidemics.…”

“…Many studies on peanut culture focus only on the endproducts ofyield and grade (7,16,17). Other researchers have examined growth characteristics of peanut to better understand energypartitioning (10) and provide information suitable for plant modeling efforts (5,33).…”