Estresse hídrico sobre caracteres morfofisiológicos e agronômicos em populações de milho

Abstract

The occurrence of estimation periods has been provoking several activities, increasing corn area cultivated in Brazil is rainfed, and as losses in annual productivity due to drought are around 15% of the total yield potential. The objective of this study was to evaluate the effect of water deficit on agronomic traits and production components on maize (Zea mays L.) genotypes and to distinguish populations with greater tolerance to water stress. The study was carried out during the period 2015/2016, in the experimental area of the Federal University of Goiás - Jatobá Campus, located in the city of Jataí / Goiás. Twenty-four genotypes were studied, 12 of which were pollinated: CC1; CCV; CRE1; CRE2; CRE3; CRE1S; MPA; MPA1; TG2R; TG2RMV; NAPPMHG; CRV-02, 10 genotypes of commercial hybrid F2 generation: HSG1, HSG2, HSG4, HSG4, HSG5, HSG6, HSG7, HSG8, HSG9 and HSG10 and two testers: DKB390 (tolerant) and BRS1030 (sensitive). The experiment was conducted in randomized blocks (DBC), in a 2 x 24 factorial scheme, (2 planting times and 24 genotypes), with 4 reps. The traits are: Male and Female Flowering (FM and FF); Interval between female and male flowering in days (IFMF); Height of plants (APL); Ear Height (AES); Stay green (STG); Prolificity (PRL); Ear length (CES); Ear diameter (DES); Hectoliter weight (PHCL) and Grain yield (PGR). The genotypes CCV, CRE3 and TG2R are potential genotypes for use in breeding programs aiming at greater tolerance to water stress. These genotypes do not differ among themselves for PGR under water deficit, with productivity of 5.76; 6.26; 5.59 and 4.48 t ha-1, respectively. The flowering interval, ear diameter and stay green are good indicative as secondary traits in the selection of water stress tolerant genotypes.