Drought Tolerance in Intervarietal Maize Hybrids

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.

Analysis of Principal Components for the Assessment of Silage Corn Hybrid Performance under Water Deficit

“…An alternative that would allow the isolated analysis of variables would be the use of genotypes with previously known behavior in the face of water deficit as instruments for comparison [9,32]. However, seeds of these genotypes are not always available, and if water productivity is to be used as a selection criterion, the grain or biomass yield for silage may be lower than achieved by modern hybrids, even under full supply of water for the plants [19].…”

“…Agriculture 2023, 13, x FOR PEER REVIEW 2 of 14 use of corn hybrids that make better use of water during development [8], which decreases the water footprint and contributes to the sustainability of agricultural systems [5]. Various methodologies and data analyses have been carried out to select corn genotypes resistant to water stress, indicating promising lines for genetic improvement programs [9]. However, this goal is challenging due to variations in the results depending on when morphological assessments were performed and given the existence of plants with low productivity and others that, by employing mechanisms to avoid dehydration, present the detriment of the yield grains and biomass [10,11].…”

“…Based on the hypothesis that water deficit has strong negative influences on productivity and on important morphological, physiological, and biochemical characteristics of maize plants [6][7][8][9][10][11]13], different plant cultivars can have different responses to water deficit, which can lead to variations in productivity and quality of harvested products. Furthermore, different ways of analyzing the results should be tested in order to better detect differences in and groupings of materials that are more tolerant to water deficits.…”

Importância de bioprotetores na mitigação do déficit hídrico em culturas de safrinha

“…Em torno de 45% das áreas agrícolas são afetadas pelo déficit hídrico, interferindo diretamente no rendimento final de várias culturas no período de safrinha, tornando-se um grande problema (ROCHA et al, 2021). Em virtude disso, ocorre a redução da área foliar, consequentemente, a menor interceptação de radiação solar na folha.…”