As an effect of climate change caused by global warming, optimum sowing date of some arable plants requiring high temperature can change in the future. Optimum sowing date is crucial from the aspect of adaptation to rapidly changing conditions in the case of maize yield, especially in dry years. With the decrease of fossil fuels, usage of maize as bioethanol is becoming an increasingly important topic. Therefore, the analysis of the nutritional parameters of maize is strongly reasonable and this factor is also affected by sowing date.

During our experiment, we were interested in the effect of sowing date on new modern hybrids appearing on a yearly basis in terms of yield results and nutritional parameters. The experiments took place in the Demonstration Garden of the Institute of Crop Sciences in 2012 and 2013. In this article we examined the specific reaction of three hybrids (DKC 4590, DA Sonka, Szegedi 386) to sowing date.

As an effect of the conditions in the two similarly extreme crop years, sowing dates caused significant differences both in yield and crop quality of the examined hybrids.

The crop year of 2012 was extreme from the climate point of view, and the weather can be also considered extremely antinomic with regards to maize production. The prevailing dry conditions during the winter and spring months affected germination and the initial development of plants adversely. The favorable weather in May and June provided ideal conditions for the intensive growing and generative processes, while the lack of rain in August and September had a harmful effect on grain filling.

Based on the experiment results of 2012, it can be concluded that in the dry crop year the hybrid DKC 4590 with shorter growing season can be more safely sown even at the late sowing date, while in the case of hybrids DA Sonka and Szegedi 386 with longer growing season, application of late sowing date can cause a yield loss of 2–3 t ha-1.

Results prove that among the analyzed hybrids, DKC 4590 is the hybrid with the highest yield potential and starch content, and hybrid Szegedi 386 is outstanding in terms of oil and protein content.

In 2013, the yield of all three hybrids considerably decreased compared to yield results with the first sowing date, due to the strong cold period following the second sowing date. Due to inland inundation in early spring, sowing dates needed to be significantly postponed, which affected yield results, although the tendency of sowing dates was similar to the previous year.

Analyses of nutritional parameters also confirm that higher yield potential occurs with higher starch content. Averaged over the different sowing dates, the hybrid DA Sonka produced the highest yield (10.1 t ha-1) with the highest starch content (73.69%). Hybrid Szegedi 386 had the highest oil content, while hybrid DKC 4590 was outstanding in terms of protein content.

Keywords: maize, sowing date, grain moisture content, nutritional value parameters