Cattle Grazing Affects Peanut Root Characteristics in a Bahiagrass-Based Crop Rotation System

Abstract

The critical aspect of production agriculture in the southeastern US with increasing associated costs is to improve economic and agronomic sustainability. A four yr sod-based rotation system consisting of two yr of bahiagrass (Paspalum notatum Fluegg´e) (grazed or nongrazed) followed by a yr of peanut (Arachis hypogaea L.) and a yr of cotton (Gossypium hirsutum L.), each with winter cover crop (grazed or non-grazed) was established in Marianna, FL. The effect of grazing on root parameters (length, volume, surface area, and diameter) of peanut was observed using a mini-rhizotron. There were differences in several root parameters between grazed and non-grazed plots including: peanut root length (307 mm in grazed vs 167 mm in nongrazed), volume (50 mm 3 in grazed vs. 23 mm 3 in non-grazed), surface area (399 mm 2 in grazed vs. 197 mm 2 in non-grazed), and diameter (2.4 mm in grazed vs. 1.7 mm in non-grazed). Roots at the 45-60 cm and 60-75 cm depths had significantly greater length in the grazed than the non-grazed plots. Likewise, surface area was significantly greater in the grazed plots at the 30-45 cm, 45-60 cm and 60-75 cm depths. Grazed plots at the 40-65 cm depths showed significant increase in root diameter. No significant difference in peanut yield was observed for the grazed or non-grazed treatments. A more developed root system associated with cattle grazing in the sod-based rotation system may enable peanuts to be more resilient in adverse environmental conditions such as drought stress, enhance nutrient cycling without affecting yield, thereby improving longterm sustainability.

Nitrogen calibration strip: An on‐farm tool to further reduce N requirements in cotton on an integrated crop‐livestock rotation system

“…The high lint yields attained with the moderate N rates may be attributed to cattle grazing. Grazing winter crops has shown to increase peanut and cotton yields with increased root development in terms of root length, surface and root volume (Loison et al, 2012; Marois et al., 2002; Sidhu et al., 2018) along with enhanced microbial and enzyme activity and nutrient recycling (Anguelov et al., 2011; George et al., 2013; D. L. Wright et al, unpublished data, 2010).…”

“…Every year each quadrant changed crop to the following phase based on the rotation. The management of rotation system in Greenwood, FL, is detailed in Sidhu et al (2018).…”

Long‐term integration of bahiagrass into a cover‐cropped and strip‐tilled peanut–cotton rotation has a limited effect on soil carbon and other soil properties

“…The limited reactivity of coarse‐textured soils in the Southeast could also result in the saturation of the soil's sorption capacity for C and/or nutrients (Castellano et al., 2015; Six et al., 2002), which could result in C and/or nutrient movement and accumulation deeper in the soil profile. Furthermore, growing a perennial grass for half of the rotation should result in greater and deeper root biomass in the SBR system (Katsvairo et al., 2007b; Sidhu et al., 2018), with potential impacts on nutrient and C cycling and stratification, through uptake, biological uplift, and/or deposition (Katsvairo et al., 2006). Bahiagrass could also impact nutrient cycling via differences in inputs (e.g., lower fertilizer inputs) and/or outputs (e.g., multiple cuttings removing more biomass and nutrients than peanut and cotton harvest), which would affect nutrient balances and soil nutrient concentrations in the SBR system.…”