Influencia de las nanopartículas de óxido de zinc sobre la calidad fisiológica y sanitaria de la semilla de maíz nativo (Zea mays L.)

Abstract

In the present study, the evaluation of zinc oxide nanoparticles (ZnO NPs) on the improvement of the physiological and sanitary quality of a Mexican landrace of red maize was carried out by means of the standard germination tests (SG) and the accelerated aging test (AA). Regarding the physiological quality, a significant increase in seed germination was found in both tests with the use of ZnO NPs, being more noticeable in the AA (90%) in comparison with the Control group (68%). The coating containing only gelatinized starch appeared to maintain seed germination (80%). These results indicate that the starch-coating containing ZnO NPs protected and stimulated germination when seed were subjected to conditions of abiotic stress (40°C and 100% RH). Likewise, it was found that the ZnO NPs protected the seeds against certain pathogenic microorganisms such as fungi and bacteria in both germination tests; consequently, an average contamination of 37% and 8% was observed for the SG and AA, respectively, in comparison with the Control group (70 and 40%, respectively). Additionally, the ZnO NPs significantly improved some seedlings traits such as shot length, shoot diameter, radical length, and number of secondary roots. Fourier transform infrared spectroscopy with attenuated total reflection (FTIR-ATR) confirmed a higher production of biomolecules (carbohydrates, proteins, and lipids) and structural molecules (cellulose, hemicellulose, and lignin) in the seedlings treated with ZnO NPs. From these results, it is concluded that ZnO NPs improved the physiological and sanitary quality of the native maize seed.