Phenotyping a New Maize Shoot Mutant in Inbred and F1 Hybrid Genetic Backgrounds

• Main Author: McLaughlin, Sean
• Format: Dissertation
• Language: English
• Published: ProQuest Dissertations & Theses 01-01-2023
• Subjects: Genetics; Molecular biology; Plant sciences
• ISBN: 9798379737948

Maize mutants are best characterized by first converging mutant alleles into a uniform, typically inbred genetic background and then phenotyping, to understand specific effects of a mutation independently of other factors that may segregate in a population. Similarly, researchers working with mutants are anecdotally familiar with mutant phenotypes differing between inbred and hybrid genetic backgrounds. On the other hand, in agriculture and thus industry hybrid maize is used for crops and an F1 hybrid displays phenotypes distinct from its inbred parents. Therefore, we are quantifying phenotypic differences for a shoot architecture mutant allele in both inbreds and hybrids by conducting field phenotyping and comparing observed traits. We have addressed this question by studying a novel, recessive mutant initially discovered in a B73/W22 hybrid background given the temporary name leafy* (lfy*) due to some resemblance to mutants of the maize Zea FLORICULA/LEAFY (zfl) genes, homologs of the Arabidopsis LEAFY gene. lfy* mutants have a range of shoot phenotypes making them appropriate for studying this question. The original mutant allele was introgressed into four standard corn belt inbreds (A619, B73, Mo17 and W22) which were then used to also produce wildtype and mutant lfy* progeny within uniform, F1 hybrid backgrounds. Inbred and hybrid populations were phenotyped in the field to identify affected characteristics. From these results we present an overview of the lfy* mutant phenotype and compare it in hybrids versus inbreds.