Diallel mixed-model analyses to select superior maize parental lines for Azospirillum brasilense and nitrogen-use efficiency

Abstract

Breeding new maize varieties that take up more N from the soil and increase N fixation is a crucial source of combined nitrogen in agricultural systems. Thus, this study aimed to select superior maize parental lines efficient in the use of nitrogen and Azospirillum brasilense. Three experiments were conducted in two agricultural seasons aiming to allocate all diallel hybrids in three different nitrogen conditions. The experiments were performed in a RCB design with two replications, and the diallel was analyzed using the mixed model approach. The general combining ability and Azospirillum use efficiency were applied to select the best parental line. The most promising hybrid combinations were "I-08 x II-06", "I-02 x II-04", and "I-01 x II-02". Parents involved were selected for the development of hybrids. Parents I

Maternal inheritance in the efficiency of use of Azospirillum brasilense in maize

“…The experiment by Pereira & Tozoni (2017) indicates favorable results depending on the affinity of the cultivar with the microorganism strain. This corroborates Hungria (2011) and other authors who observed functional nitrogenase activity depending on the bacterial strain and the genetic material of maize (Brusamello-Santos et al, 2017;Pereira-Defilippi et al, 2017;Buzinaro et al, 2018;Revolti et al, 2018).…”

“…In the experiment by Buzinaro et al (2018), the estimates for the effects of GCA for efficiency to Azospirillum in plant height, ear height, and grain yield, as well as for the effects of SCA for efficiency in grain yield, were significant. The authors concluded that additive effects influence the genetic control of the three traits in question, and that nonadditive effects influence the genetic control of the trait grain yield.…”

“…The use of A. brasilense in maize favors the production of phytohormones that stimulate root growth. This improves plant nutrition and photosynthetic activities, increasing chlorophyll content, biomass production, and plant height (Hungria, 2011;Buzinaro et al, 2018;Revolti et al, 2018). brasilense for grain yield.…”

“…However, this assimilation can take place from biological fixation through the action of microorganisms (Montañez et al, 2008). Associative bacteria, such as those of the genus Azospirillum, can benefit maize plants, including providing part of the necessary nitrogen (Hungria, 2011;Buzinaro et al, 2018;Revolti et al, 2018).…”

Accounting for spatial trends in multi-environment diallel analysis in maize breeding

“…The mixed model methodology, or the residual maximum likelihood (REML)/best linear unbiased prediction (BLUP) [ 16 , 17 ] procedure, has been widely adopted for analyzing MET in plant breeding [ 18 – 21 ]. However, diallel analyses are still underused [ 22 ], even being an effective procedure for genetic evaluation [ 23 ].…”