Water Use Efficiency in Popcorn (<i>Zea mays</i> L. var. everta): Which Physiological Traits Would Be Useful for Breeding?
Jhean Torres Leite,
Antonio Teixeira do Amaral Junior,
Samuel Henrique Kamphorst,
Valter Jário de Lima,
Divino Rosa dos Santos Junior,
Kátia Fabiane Mereiros Schmitt,
Yure Pequeno de Souza,
Talles de Oliveira Santos,
Rosimeire Barboza Bispo,
Gabrielle Sousa Mafra,
Eliemar Campostrini,
Weverton Pereira Rodrigues
Affiliations
Jhean Torres Leite
Center of Agricultural Science and Technology, Laboratory of Plant Breeding, Darcy Ribeiro State University of Northern Rio de Janeiro, Av. Alberto Lamego, 2000, Campos dos Goytacazes 28013-602, RJ, Brazil
Antonio Teixeira do Amaral Junior
Center of Agricultural Science and Technology, Laboratory of Plant Breeding, Darcy Ribeiro State University of Northern Rio de Janeiro, Av. Alberto Lamego, 2000, Campos dos Goytacazes 28013-602, RJ, Brazil
Samuel Henrique Kamphorst
Center of Agricultural Science and Technology, Laboratory of Plant Breeding, Darcy Ribeiro State University of Northern Rio de Janeiro, Av. Alberto Lamego, 2000, Campos dos Goytacazes 28013-602, RJ, Brazil
Valter Jário de Lima
Center of Agricultural Science and Technology, Laboratory of Plant Breeding, Darcy Ribeiro State University of Northern Rio de Janeiro, Av. Alberto Lamego, 2000, Campos dos Goytacazes 28013-602, RJ, Brazil
Divino Rosa dos Santos Junior
Center of Agricultural Science and Technology, Laboratory of Plant Breeding, Darcy Ribeiro State University of Northern Rio de Janeiro, Av. Alberto Lamego, 2000, Campos dos Goytacazes 28013-602, RJ, Brazil
Kátia Fabiane Mereiros Schmitt
Center of Agricultural Science and Technology, Laboratory of Plant Breeding, Darcy Ribeiro State University of Northern Rio de Janeiro, Av. Alberto Lamego, 2000, Campos dos Goytacazes 28013-602, RJ, Brazil
Yure Pequeno de Souza
Center of Agricultural Science and Technology, Laboratory of Plant Breeding, Darcy Ribeiro State University of Northern Rio de Janeiro, Av. Alberto Lamego, 2000, Campos dos Goytacazes 28013-602, RJ, Brazil
Talles de Oliveira Santos
Center of Agricultural Science and Technology, Laboratory of Plant Breeding, Darcy Ribeiro State University of Northern Rio de Janeiro, Av. Alberto Lamego, 2000, Campos dos Goytacazes 28013-602, RJ, Brazil
Rosimeire Barboza Bispo
Center of Agricultural Science and Technology, Laboratory of Plant Breeding, Darcy Ribeiro State University of Northern Rio de Janeiro, Av. Alberto Lamego, 2000, Campos dos Goytacazes 28013-602, RJ, Brazil
Gabrielle Sousa Mafra
Center of Agricultural Science and Technology, Laboratory of Plant Breeding, Darcy Ribeiro State University of Northern Rio de Janeiro, Av. Alberto Lamego, 2000, Campos dos Goytacazes 28013-602, RJ, Brazil
Eliemar Campostrini
Center of Agricultural Science and Technology, Laboratory of Plant Breeding, Darcy Ribeiro State University of Northern Rio de Janeiro, Av. Alberto Lamego, 2000, Campos dos Goytacazes 28013-602, RJ, Brazil
Weverton Pereira Rodrigues
Centro de Ciências Agrárias, Naturais e Letras, Universidade Estadual da Região Tocantina do Maranhão, Av. Brejo do Pinto, S/N, Estreito 65975-000, MA, Brazil
To ensure genetic gains in popcorn breeding programs carried out under drought conditions knowledge about the response of morphophysiological traits of plants to water stress for the selection of key traits is required. Therefore, the objective was to evaluate popcorn inbred lines with agronomically efficient (P2 and P3) and inefficient (L61 and L63) water use and two hybrids (P2xL61 and P3xL63) derived from these contrasting parents, cultivated under two water regimes (WW watered—WW; and water-stressed—WS) in a greenhouse, replicated five times, where each experimental unit consisted of one plant in a PVC tube. Irrigation was applied until stage V6 and suspended thereafter. Individual and combined analyses of variance were performed and the genotypic correlations and relative heteroses estimated. The water use efficient inbred lines were superior in root length (RL), root dry weight (RDW), and net CO2 assimilation rate (A), which were the characteristics that differentiated the studied genotypes most clearly. High heterosis estimates were observed for RL, SDW, leaf width (LW), leaf midrib length (LL), and agronomic water use efficiency (AWUE). The existence of a synergistic association between root angle and length for the characteristics A, stomatal conductance (gs), and chlorophyll concentration (SPAD index) proved most important for the identification and phenotyping of superior genotypes. Based on the study of these characteristics, the higher AWUE of the previously selected inbred lines could be explained. The results reinforced the importance of root physiological and morphological traits to explain AWUE and the possibility of advances by exploiting heterosis, given the morphophysiological superiority of hybrids in relation to parents.
