Yield, Nutritional Composition, and In Vitro Ruminal Digestibility of Conventional and Brown Midrib (BMR) Corn for Silage as Affected by Planting Population and Harvest Maturity

Abstract

The objective of this study was to evaluate the effects of corn-planting population, using two conventional (Conv) and two brown-midrib (BMR) hybrids, and maturity stage at harvest on forage dry-matter (DM) yield, silage quality, and in-vitro fiber digestibility. The study was conducted in two fields with contrasting production potential, where both corn hybrids were planted at a theoretical planting population of 59,000, 79,000, and 99,000 seeds/ha. Corn was harvested at the early-dent (early) or 2/3 milk-line (late) maturity stage. An interaction between planting population and field existed for biomass yield. We observed a consistent increase in forage yield with increased planting population only in the field of higher production potential. Corn hybrids that contained the BMR trait did not penalize yield but had a consistently higher digestibility of neutral detergent fiber (aNDFom) compared to conventional hybrids. Except for starch concentration, no interaction existed between planting population and maturity for forage yield, fiber digestibility, and nutritional composition. A response to increasing planting population on starch concentration was observed only when corn was harvested at the L = late maturity stage. In conclusion, increasing corn-planting population may increase forage yield, but such an effect may depend on the soil’s growing potential. In addition, planting population had a negligible effect on the nutritional composition and fiber digestibility of corn silage and was minimally affected by the maturity stage at harvest.

Moisture relationships among conventional and brown‐midrib corn hybrids for silage

“…The regressions of ear DM per plant on whole plant moisture did differ between BMR and CONV, based on lack of 95% confidence interval overlap across the entire range. Total dry matter yield per plant at the 68% whole plant harvest moisture stage did not differ between BMR and CONV, agreeing with results from Peña et al., 2023, but ear DM yield per plant was 7.5% greater for CONV compared to BMR hybrids.…”

“…Although BMR corn hybrids have been consistently criticized in the past for reduced yields (yield drag), reduced starch content, lodging, and lack of disease resistance (Rankin, 2016), BMR hybrids are constantly being improved, and a recent study concluded there was no yield penalty for two BMR hybrids compared to two CONV hybrids (Peña et al., 2023). Even though BMR corn hybrids are often visually dryer than CONV hybrids, BMR hybrids are often considered to retain moisture longer than CONV hybrids in the same relative maturity (RM) group (Cherney & Cox, 2020), particularly in cool weather.…”

Environmental Life Cycle Assessment of Silage Maize in Relation to Regenerative Agriculture

“…Maize is not only an important staple crop for millions of people worldwide but also an important crop now emerging as a type of high-energy silage crop [21], used to produce animal feed due to its high feeding value [22]. The corn crop provides an excellent combination of high dry-matter yield per hectare and the quality of the biomass produced [23]. Silage corn is an important crop for the Czech Republic also as a crop for energy use in biogas stations.…”