Characterizing Root Morphological Traits in 65 Genotypes of Foxtail Millet (Setaria italica L.) from Four Different Ecological Regions in China

As an indispensable grain crop, foxtail millet (Setaria italica L.) is becoming a functional food in China because of its abundant nutrients. However, low rainfall and uneven precipitation limit growth production, especially northwest China. Understanding the root phenotypic characteristics critical for utilizing to breed new varieties with improved resource-use efficiency better adaptation harsh environments. The present study characterized variability morphological traits at seedling stage 65 genotypes selected from four ecological regions across seven provinces plants were assessed after 21 days germination pouches, 48 shoot measured. results showed large variation among traits. Among measured traits, dry mass, maximal length, surface area, tissue density contributed most principal components. Root area ratio volume significantly correlated length ratio, respectively, while weight negatively diameter (p < 0.01). Shoot number, total mass closely each other. 5-cm sections decreased top bottom along system. regions, early maturing had greatest density, those generally largest system, about 2.2 times more than northeast (the shortest system). genotypic correlations form basis breeding cultivars.