Laser irradiation effects on field performance of maize seed genotypes

The paper presents a study on the effects of low intensity laser irradiation on field performance of maize hybrid seeds (Zea mays L.). Pre-sowing laser irradiation treatment on the seeds was done, during 20 s, by using a diode laser with output power of 27.4 mW at 650 nm wavelength. To evaluate the pre-sowing laser irradiation effects on the seed field performance, a randomized complete block experimental design with 5 replications was used for statistical analysis. The maize seed genotypes used in the present study were VC-AZ, VS-AM and MT-1415. Also, by using photoacoustic spectroscopy, the optical absorption coefficient (β) of each maize genotype was obtained. In order to evaluate the effects of laser irradiation on the seed field performance some vigour tests were done and the results are showed. In the case of MT-1415 a negative biostimulation for seedling emergence percentage, seedling emergence rate and chlorophyll a content was observed, compared to the control experiment ie without irradiation. For VC-AZ and VS-AM genotypes no significant effects were obtained for the same vigour tests, as compared to the control experiment. These results show that it is necessary to find the optimal irradiation parameters to induce positive biostimulation in maize seeds, which also depends on the seed genotype.