Harvest frequency effects on herbage characteristics of ‘Mavuno’ brachiariagrass

Abstract

Mavuno' brachiariagrass (Brachiaria spp.) is a warm-season perennial grass cultivar released in Brazil with potential to be used as forage in subtropical regions. The objective of this study was to evaluate herbage accumulation (HA), nutritive value, and the persistence of Mavuno under different harvest frequencies. The experiment was conducted in Ona, FL, from April to November in 2016 and 2017. Treatments were the factorial arrangement of four grasses: Jiggs bermudagrass [Cynodon dactylon (L.) Pers], 'Tifton 85' bermudagrass (Cynodon spp.), 'Mulato II' brachiariagrass, and Mavuno and two regrowth intervals (3 or 6 wk), distributed in a randomized complete block design with four replicates. Mavuno and Mulato II had similar total annual HA (11.0 Mg ha −1 ), and in vitro digestible organic matter (IVDOM, 644 g kg −1), but greater total annual HA and IVDOM than Jiggs (7.8 Mg ha −1 and 500 g kg −1 ) and Tifton 85 (8.4 Mg ha −1 and 550 g kg −1 ). Mavuno had the least crude protein (CP) among all treatments (111 vs. 124 g kg −1 ), and CP and IVDOM were greater at the 3-wk regrowth interval than at the 6-wk interval (130 vs. 111 g kg −1 and 610 vs 548 g kg −1 , respectively). Root mass was greater at 3 wk than at 6 wk for Tifton 85 (9.4 vs. 5.4 Mg ha −1 ) but was not affected by regrowth interval for Jiggs, Mavuno, and Mulato II (6.5 Mg ha −1 ). Mavuno and Mulato II had superior HA and IVDOM, and Mavuno may be a viable forage source in subtropical regions.

Soil organic carbon sequestration calculated from depth distribution

“…estimated from soil depths of 0–30, 30–60, and 60–90 cm was 3.3 ± 1.7, 0.9 ± 0.5, and 0.9 ± 0.5 Mg ha –1 , respectively (Adams et al., 1966). In other studies, root mass to 20‐cm depth only was 6.7 ± 1.2 Mg ha –1 under a variety of warm‐season grasses in Florida (Siqueira da Silva et al., 2019), 9.4 ± 1.5 Mg ha –1 under bermudagrass with different N fertilizer levels (Liu et al., 2017), and 2.5–5.5 Mg ha –1 under bermudagrass (Alderman et al., 2011). Warm‐moist conditions persist throughout the year in this region and lead to high decomposition rates, contributing to relatively low SOC concentrations.…”

Herbage accumulation, nutritive value, and persistence of new warm‐season perennial grasses

“…There was less variation in IVDOM during the experimental period in Citra than Ona; however, the experimental period started in the summer and did not capture the potential variation from the spring to summer months. The IVDOM was greater in the last autumn harvest at both locations because of limited growth, and a similar response was previously observed in brachiariagrass and bermudagrass at the same location (Siqueira da Silva et al, 2020).…”

“…Therefore, it was promising that Camello and Spain had a similar HA in the spring and autumn to Jiggs (Ona location), because this is a period of shortage of forage for most forage and livestock producers in the southeastern United States. It has been observed that ‘Mulato II’ and ‘Mavuno’ brachiariagrasses had greater HA than Jiggs in the summer at the same location, probably because of the upright architecture of the leaves and their better light interception efficiency (Siqueira da Silva et al., 2020). There are limited reports of guineagrass HA in the southeastern United States, but Silveira et al.…”

Comparison of Nutritive Values of Tropical Pasture Species Grown in Different Environments, and Implications for Livestock Methane Production: A Meta-Analysis

“…The age of the plants at their time of utilisation (by grazing or cutting) is an important aspect to consider in tropical pasture production, as this significantly affects their yield and chemical composition, which consequently affects milk production [ 12 ]. While dry matter (DM) production significantly increases with maturity, the digestibility and the crude protein (CP) content both rapidly decline with advancing plant maturity [ 13 , 14 ]. Although forage maturity reduces its nutritive value, environmental and agronomic management factors can alter the relationship between plant maturity and forage nutritive value [ 13 , 15 ].…”

“…While dry matter (DM) production significantly increases with maturity, the digestibility and the crude protein (CP) content both rapidly decline with advancing plant maturity [ 13 , 14 ]. Although forage maturity reduces its nutritive value, environmental and agronomic management factors can alter the relationship between plant maturity and forage nutritive value [ 13 , 15 ]. Herbage accumulation and the nutritive value of grasses are both strongly affected by management factors, such as defoliation (grazing and cutting) frequency, intensity, and the application of N fertiliser (amount and frequency) [ 16 , 17 ].…”