Genetic responses of traits relationship to components of nitrogen and phosphorus use efficiency in maize

Abstract

ABSTRACT. This study had three objectives: i) to observe maize inbred lines response to nitrogen (N) and phosphorus (P) acquisition as well as their utilization efficiencies and traits of root morphology in contrasting levels of these nutrients, ii) to study the relationship between root morphology and nutrient use efficiencies for both nutrients, and iii) to identify contrasting parents with components N and P use efficiency for an inheritance study. We evaluated 15 inbred lines in two experiments conducted in contrasting conditions of N and P. We evaluated the shoot, root traits and nutritional efficiencies and observed the genetic variability for most traits. Selection can be practiced for most of these traits in specific environments. Under conditions of nutritional stress, average and heritability estimates were of lesser magnitude. In this study, the shoot and root morphology traits were shown to be associated with the acquisition efficiency of both N and P in all of the environments that were evaluated.Keywords: Zea mays, acquisition and utilization efficiencies, root morphology, abiotic stress, REML/BLUP.Respostas genéticas de caracteres relacionados aos componentes da eficiência no uso de nitrogênio e fósforo em milho RESUMO. Esse estudo teve três objetivos: i) observar a resposta de linhagens de milho quanto às eficiências de absorção e de utilização de N e P e de caracteres de morfologia de raiz em níveis contrastantes destes nutrientes; ii) estudar as relações entre caracteres de morfologia de raiz e as eficiências nutricionais para ambos os nutrientes e iii) identificar genitores contrastantes quanto aos componentes da eficiencia no uso de N e P para estudo de herança. Foram avaliadas 15 linhagens de milho em dois experimentos conduzidos em condições contrastantes de N e P. Avaliou-se parte aérea, caracteres de raiz e eficiências nutricionais e Observou-se variabilidade genética para a maioria dos caracteres avaliados. A seleção pode ser praticada para a maioria destes caracteres em ambientes específicos. Em condições de estresse nutricional, as médias e herdabilidades apresentaram estimativas de menor magnitude. Nesse estudo, os caracteres parte aérea e morfologia de raiz apresentaram elevada associação com a eficiência de absorção, tanto para N como para P, em todos os ambientes avaliados.Palavras-chave: Zea mays, eficiências de absorção e de utilização, morfologia radicular, estresse abiótico, REML/BLUP.

Inheritance of Nitrogen Use Efficiency in Inbred Progenies of Tropical Maize Based on Multivariate Diallel Analysis

“…This indicates that the quantity of favorable alleles donated by the parents changes among the environments. This corroborates results found by DoVale et al [2] and DoVale et al [27]. Thus, parents that promote an increase in the mean values of their hybrids evaluated in a certain environment and level of N might not contribute in a similar way when the hybrids are evaluated in another environment and level of N. This implies that there is low precision in the prediction of the behavior of the hybrids under different environments.…”

Comparative Analysis of Root Traits and the Associated QTLs for Maize Seedlings Grown in Paper Roll, Hydroponics and Vermiculite Culture System

“…In the sand and vermiculite mixed system, maize lateral root length and axial root length had significant positive correlations with NupE in both high and low N treatment. Additional significant positive correlations were found between axial root length and PupE in high and low P treatment (DoVale et al, 2013). In the hydroponics system, seminal root number (SRN) showed significant correlations with NupE in a N deficient condition (Li et al, 2015).…”

Accuracy and simultaneous selection gains for N-stress tolerance and N-use efficiency in maize tropical lines

“…We used sixty four (64) tropical maize lines, obtained from the germplasm from Viçosa, MG, Brazil, to generate a population with high genetic variability to assess N-use efficiency and N-stress tolerance (Dovale et al, 2013). The population structure analysis revealed three tropical heterotic pools, which have been used worldwide and by Brazilian maize seed companies.…”