Morphological and Genetic Characterization of Local Maize Accessions from Emilia Romagna Region, Italy

Italian maize germplasm is particularly rich in local materials and each region is characterized\r\nby the presence of peculiar local varieties deriving from centuries of adaptation, selection\r\nand cultivation. While the introduction of hybrids, during the 1950s, led to the disappearing of\r\nmany of these varieties, some have been maintained in cultivation by farmers, frequently in marginal\r\nareas, as a kind of family heritage. Local varieties were identified throughout field surveys carried\r\nout in recent years. The discovery of a traditional popcorn variety over the most common flint and\r\nsemi-flint materials used for production of polenta was interesting. Since these varieties have never\r\nbeen adequately described and reported in scientific literature, this study was aimed to solve this\r\nlack of knowledge on recently discovered local maize populations. Characterization represents the\r\nfirst step of a process focused on the preservation and possible exploitation of important genetic\r\nresources. Traditional materials are a useful reservoir of genes for adaptation to local conditions and\r\nclimate changes. Adequate breeding programs can use such germplasm for developing new and\r\nmore resilient varieties. These local materials have been characterized at the morphological level\r\nhighlighting plant, ear and kernel differences. Genetic characterization, carried out on 455 individuals\r\nby the use of 10 SSR markers, revealed 62 different alleles ranging from four for markers phi127,\r\nphi076 and phi084 to nine for marker p-bnlg176. The landraces are well distinguishable at genetic level\r\nsince 40% of genetic variability is present among accessions. Five landraces are characterized by the\r\npresence of private alleles and heterozygosity levels are generally good. These findings support the\r\npossibility to correctly preserve local materials through in situ conservation. Phylogenetic analysis\r\nevidenced the presence of varietal clusters, the clearest one formed by three red-pigmented accessions.\r\nSTRUCTURE analysis revealed that five landraces have a well-defined genetic attribution while the\r\nremaining two (EMR04-Mais Rosso di Rasora and EMR10-Mais del Principe di Scavolino) are both\r\nconstituted by two different backgrounds.