Abstract
ABSTRACT In the period of planting of second-season maize, there is high climatic instability with greater probability of occurrence of water deficit. This is one of the factors that most cause reduction in maize grain yield. In this context, the aim was to identify stable, irrigation-responsive and drought-tolerant maize genotypes. The experiments were conducted in Mococa / SP and Tatuí / SP, at Instituto Agronômico, in two assays, one under full irrigation conditions and the other under water stress. The experimental design was randomized blocks with 3 replicates. Male flowering, female flowering, plant height, ear height, hectoliter weight, one hundred grain weight and grain yield were evaluated. Joint analysis of variance and stability analysis were performed by the GGEBiplot method. Significant genotype and site effects were observed for all traits. Significant effects of genotype x site interaction were found for all traits except ear height and male flowering. The characteristics most affected by water deficit were male flowering, plant and ear heights and grain yield. Genotypes F2 BM709 x PopTol 2, IAC 46 x PopTol 2, F2 30K75 x PopTol 3 and F2 BM709 x PopTol 3 are considered ideotypes because of their high grain yield, phenotypic plasticity and drought tolerance.
Highlights
In Brazil, the planted area of late-season maize surpassed the area of the summer season
The maize planting system during the second season is subject to greater climatic instability with higher probability of occurrence of water deficit periods, since the late-season maize encompasses the end of the rainy season (SCHLICHTING et al, 2014)
The primary consequence of water deficit is the stomatal closure that occurs with the decrease in leaf water potential, which invariably coincides with the reduction of photosynthesis and transpiration
Summary
In Brazil, the planted area of late-season maize surpassed the area of the summer season. It is essential to identify water deficit-tolerant genotypes with a high production potential and that have wide adaptability and stability In this context, the use of methodologies to study the genotypes x environments interaction may result in more accurate selection of genotypes more tolerant to water deficit and more responsive to adequate water conditions. The hybrid from cross between F2 populations may represent an alternative of hybrid seed with affordable prices, good genetic potential and high grain yield, ideal for small and medium producers (GUIMARÃES et al, 2014) Obtaining seeds from these hybrids is simplified because the stages of production and multiplication of strains are eliminated from the process. The objectives were to evaluate intervarietal hybrids of maize from a 13x2 half-diallel, identify genotypes with higher yield and stability, responsive to irrigation and tolerant to water deficit, aiming to obtain new hybrids for the seed market and new sources of tolerance for breeding programs
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
