Agronomic and Economic Comparisons of Row Spacing and Row Patterns for Peanut.

Peanuts (Arachis hypogaea L.) are traditionally grown in 91 cm row spacing, but with increases in corn (Zea mays L.) and soybean (Glycine max [L.] Merr.) acreage in primary peanut producing areas, there is growing interest in converting to 76 cm rows for uniform equipment settings.  The objectives of this research were to compare 76 cm single row pattern to 91 cm single and 91 cm twin row pattern plantings of peanut for yield, grade, tomato spotted wilt (Tospovirus) (TSW) incidence, and economic impact.  Two peanut cultivars (‘Georgia Green’ and ‘C-99R’) were used in conjunction with the row spacing treatments, making a 3 x 2 factorial experiment with treatments arranged in a randomized complete block design, and six replications.  Yields were higher on a per area basis using the 76 cm single rows (6840 kg ha^-1) than either the 91 cm single (6043 kg ha^-1) or 91 cm twin rows (6079 kg ha^-1).  There was no difference in TSW or grade among the row spacing treatments, although C-99R (4.0 %; 76.3%) had lower TSW incidence and grade respectively than Georgia Green (10.7 %; 78.2%).  The yield advantage for the 76 cm single rows is a result of having area to plant additional rows in a given field as opposed to an increase in plant performance at the reduced spacing.  It was also noted that there was quicker lapping of row middles in the 76 cm single row pattern than the 91 cm single rows, which should be an advantage in suppressing mid-season weed competition.  Net returns to management and land averaged highest for 76 cm rows ($635 ha^-1 – Georgia Green; $472 ha^-1 – C-99R).  These results show reduced row spacings can provide an advantage over traditional row spacings in peanut production.