Forage Quality Variation among Maize Inbreds: In Vitro Digestibility and Cell‐Wall Components

Abstract

Forage maize (Zea mays L.) hybrids with improved feeding value might be produced if breeders had better information about inbred variation in maize for stover quality. This study was conducted to determine variation for in vitro digestible dry matter (IVDDM) and cell‐wail componenct oncentrations amonge lite maize inbred lines and to determine the relationship between IVDDM and cell‐wail components. Leaf blades and elongated basal stem internodes of 45 maize inbred lines grown near Ames, IA, were sampled at an early harvest near silking, and stem internodes were sampled again at a late harvest near physiological maturity. Significant variation existed among the inbreds for IVDDM and cell‐wall components. Variation was greatest in late‐harvest stems and least in leaf blades. The IVDDM ranged from 262 to 650 g kg−1 dry matter (DM) in late‐harvest stems, from 465 to 727 g kg−1 DM in early‐harvest stems, and from 580 to 676 g kg−1 DM in leaf blades. Stem IVDDM was most closely associated with stem neutral detergent fiber concentration both at the early harvest (r = −0.74) and at the late harvest (r = −0.82), whereas leaf IVDDM was most closely associated with leaf lignin concentration (r = −0.61). Early‐harvest stem IVDDM was not closely associated with leaf IVDDM (r = 0.31) or late‐harvest stem IVDDM (r = 0.40). Hence, effective selection for improved IVDDM of maize stover may require total stover sampling near physiological maturity.