Importance of the stover and ear of corn populations in the genetic improvement of forage quality

Abstract

tropical and subtropical germplasm, F1 hybrids and F2 hybrid generations. The experimental material was evaluated in Aguascalientes, Mexico, in a split plot experiment with three replications, in which plots were Groups and subplots populations within Groups. The earliest group of highland populations had the highest whole plant and stover forage quality (P<0.05). in vitro digestibility (IVD) for this group was 75.4 % for the whole plant and 72.0 % for stover, compared to an average of 71.2 % whole plant and 64.8 % stover digestibility for all other groups. Three of the groups had significant differences between populations (P<0.05) for neutral detergent fiber (NDF), acid detergent fiber (ADF), lignin (LIG), and IVD. The largest differences were recorded in the stover, with almost no variation observed in the ear. Stover IVD differences ranged from 9.4 to 14.6 %, while ear IVD differences ranged from 2.9 to 6.1 %. High correlation coefficients (P<0.01) were determined between whole plant IVD and all stover forage quality characteristics (-0.85, -0.84, -0.84 and 0.93 for NDF, ADF, LIG, and IVD, respectively), but none were present for ear forage quality characteristics. The results suggest that selection for stover nutritional quality is a more effective way of improving whole plant nutritional value than selection for grain nutritional quality.