Genetic resources of maize (Zea mays L.): double purpose hybrids to generate grain and lignocellulosic biomass

Abstract

Maize stover (Zea mays L.) can be converted into fermentable sugars to produce ethanol by fermentation processes, similar to those occurring to forage in the rumen. The efficiency of these processes depends on the stover cell wall structure. Some authors suggested that selection for grain yield and resistance to stalk lodging could reduce forage quality and, as a result, its potential ability to produce ethanol. Therefore, finding sources of maize genetic variability appears to be a good alternative for lignocellulosic bioethanol production without compromising grain yield. During three years, 144 maize genotypes were evaluated to found favorable alleles to generate double purpose hybrids for grain and lignocellulosic biomass. They included native Argentinean populations (landraces), commercial hybrids, maize composites, and experimental silage hybrids, differing in improvement level, cycle length, grain type, and presence of BMR genes. Selection indexes were constructed using a nonparametric rank-sum index to select dual-purpose genotypes. Thus, indexes allowed to identify the superior genotypes for bio-energetic Potential and stability. Two native populations were selected for their good performance to produce grain and lignocellulosic biomass (ARZM03003, ARZM18022).