Polyethylene glicol 8000 to identify corn tolerant to water stress during germination

Introduction. The availability of water for agricultural production is essential. The production of corn, subject to the rainy season, in Mexico exceeds 70%. In the agricultural regions of the Yucatan, productions are reported in conditions of low rainfall or very erratic precipitation, which can cause total losses. A critical condition for the establishment of a crop is to have the necessary humidity that allows germination. Objective. The aim of the present work was to evaluate maize materials under simulated water stress conditions through osmotic solutions in order to identify those that can tolerate these conditions. Materials and methods. The study was carried out in the Campo Experimental Mococha of the Instituto Nacional de Investigaciones Forestales, Agrícolas y Pecuarias, during 2017; including the germination and establishment phase. Twenty-five maize materials were used under a completely random design with a factorial arrangement. A germination test was performed under simulated two stress conditions by means of the PEG 8000 (-0.50 and -0,75 MPa), also a control (0 MPa) was used. Four replicates of twenty-five seeds were done. The seeds were exposed for 24 h to the PEG 8000, subsequent, irrigations were done with distilled water. The seeds were exposed for 24 h to PEG 8000, later, the seeds were irrigated with distilled water. The germinated seeds were counted on the seventh day and reported as germination percentage. In a sample, of ten seedlings of each repetition, length and weight were measured, separately, from the aerial part and the root. Results. From the evaluated materials, the hybrids H-563, H-565 and H-568 endured a stress of -0.5 MPa, and the H-520, H-567 and HEV3B hybrids presented germination with -0.75 MPa and stood out in all the variables evaluated. Conclusion. It is possible to identify materials that will tolerate stress conditions during the germination stage.