Influence of planting date, row spacing, and reduced herbicide inputs on peanut canopy and sicklepod growth

Abstract

Sicklepod [Senna obtusifolia (L.)] is one of the most problematic weed species for peanut production in the southeastern USA. A two‐year study was conducted to evaluate the influence of peanut planting date and row spacing on sicklepod growth. Planting date was the main plot factor with early (early May), mid‐ (mid‐May), or late (early June) timings. Row spacing was the subplot factor with single row and twin rows at 13, 18, or 23 cm. For minimal herbicide use, pendimethalin was applied at peanut planting and 2,4‐DB was applied at 6 wk after planting. Peanut on twin rows at 18 and 23 cm achieved canopy closure 2 wk earlier than the single or the 13‐cm twin‐row. In 2019, sicklepod height was similar across all planting dates, while in 2020 height decreased in the order of late > mid > early planting. Sicklepod biomass in early planting was greater compared with mid and late planting in 2019, whereas biomass was greater in late planting compared with early and mid‐planting in 2020. Peanut yield was 50% greater in early and mid‐planting compared with late planting in 2019, while yield was 18% lower in the single row compared with the twin rows in 2020. The differences between the two years were attributed to greater humidity and heavy rainfall during 2020 (137 cm) compared with the 2019 (77 cm) season. We conclude that peanut planted on 18‐ or 23‐cm twin rows during the mid‐planting date has the potential to maintain yield and suppress sicklepod.

Competing with the competitors in an endless competition: a systematic review of nonchemical weed management research in peanut (Arachis hypogea) in the United States

“…Numerous studies have reported the superior weed suppressive ability of peanut using twin rows as a weed-preventive measure compared with single rows (Brecke and Stephenson 2006; Colvin et al 1985; Grichar et al 1994; Kharel et al 2022; Wehtje et al 1984). The benefits of twin-row spacing are attributed mainly to rapid canopy cover and more efficient use of light and water that give peanut a competitive advantage against weeds (Brecke and Stephenson 2006; Johnson et al 2005; Kharel et al 2022; Place et al 2010).…”

“…Numerous studies have reported the superior weed suppressive ability of peanut using twin rows as a weed-preventive measure compared with single rows (Brecke and Stephenson 2006; Colvin et al 1985; Grichar et al 1994; Kharel et al 2022; Wehtje et al 1984). The benefits of twin-row spacing are attributed mainly to rapid canopy cover and more efficient use of light and water that give peanut a competitive advantage against weeds (Brecke and Stephenson 2006; Johnson et al 2005; Kharel et al 2022; Place et al 2010). In a recent study, Kharel et al (2022) reported that twin rows spaced 18 or 23 cm apart on 91-cm centers achieved canopy closure 2 wk earlier, resulting in greater S. obtusifolia suppression and an 18% increase in yield compared with single rows spaced 76 cm apart.…”

“…The benefits of twin-row spacing are attributed mainly to rapid canopy cover and more efficient use of light and water that give peanut a competitive advantage against weeds (Brecke and Stephenson 2006; Johnson et al 2005; Kharel et al 2022; Place et al 2010). In a recent study, Kharel et al (2022) reported that twin rows spaced 18 or 23 cm apart on 91-cm centers achieved canopy closure 2 wk earlier, resulting in greater S. obtusifolia suppression and an 18% increase in yield compared with single rows spaced 76 cm apart. Similarly, S. obtusifolia control was 9% higher and yield 10% to 43% higher when peanut was seeded in the twin-row planting pattern (rows spaced 18 cm apart on 91-cm centers) compared with peanut planted in the single-row planting pattern (single rows on 91-cm centers) under different herbicide treatments (Lanier et al 2004).…”

“…Planting date can have a huge impact on weed management in peanut by affecting weed seed germination, weed growth rate, and crop vegetative growth (Linker and Coble 1990). Peanut planting dates in the United States range between mid-April and late June (Linker and Coble 1990; Kharel et al 2022). During this period, weeds have a well-defined period of emergence determined by soil moisture content and soil temperature (Egley and Paul 1986; Stoller and Wax 1973).…”

“…Therefore, peanut planting date can be manipulated as a weed-preventive measure in such a way that the ecological conditions for weed seed germination are not met during the planting timing. The peak of weed emergence and prolonged competition can also be avoided through a well-planned planting date (Kharel et al 2022). Furthermore, the planting date can be adjusted to facilitate faster growth, which can result in rapid canopy closure, increased crop competitiveness, and greater weed suppression (Kharel et al 2022).…”