Review on Genetic and Breeding for Low -N tolerance in Maize

Low soil nitrogen (Low N) is one of the major abiotic stresses causing maize yield reduction in tropics of Africa. However, genetic variation observed under low N and crossing among adaptive/NUE elite lines should be targeted for different secondary traits, economic disease and inheritance studies breeding for Low N in maize. In addition, breeding for Low N and drought have common traits indicating that common adaptive mechanism and thus, appear to develop maize genotypes that tolerance to stress and such maize genotypes exhibited high yield performance under low and high N condition across environments, is likely good for subsistence farmers in Africa for maize production. Multiple QTLs detected under Low N and high-nitrogen conditions for grain yield per plant, secondary and physiological traits. However, a direct use of these detected QTLs has been less achieved breeding for Low N tolerance in maize program, because of eQTLs. Thus, stable QTLs should be validated and fine mapping or GWAS method should detect the candidate genes for controlling NUE for low soil nitrogen in maize. Keywords: Low N, secondary traits, genotypes, NUE, QTLs DOI: 10.7176/JBAH/12-11-03 Publication date:June 30th 202