The main aim of our work was to study the impact of different sowing dates of sweet maize on harvest time, yield and damage of sweet maize ears caused by the European corn borer. In this study, two hybrids of sweet maize were included, namely the Slovenian hybrid Zarja and the USA hybrid Gold Cup. The field experiment was conducted at the Experimental field of the Biotechnical Faculty at Jable near Ljubljana. Each hybrid was planted on 6 different dates from 8th of May till 24th of June, at 8-10 days intervals. Sowing and harvesting were carried out manually. During the growth period, we recorded the dates of tasseling and silking, and the time of 'milk' maturity. The ears were harvested when they reached the appropriate stage of 'milk' maturity. We determined the length and weight of ears, and the grain rows number. Results showed that with 6 different sowing dates, from 8th May to 24th June, it was possible to provide fresh mature sweet maize ears from 13th August till 1st October. The Slovenian variety Zarja was earlier than Gold Cup. Zarja was characterised by more mature maize ears at earlier harvesting. The Gold Cup had longer, thicker and heavier ears although all recorded properties exhibited higher variability when compared to Zarja. Longest, thickest and heaviest maize ears were harvested during 1st and 2nd terms of harvest, whereas the shortest, thinnest and lightest ears were recorded during last 6th terms. The percentage of damaged ears by the European corn borer was the same in both hybrids. The highest percentage of damaged ears, in both hybrids, were recorded during the 6th term of harvest.
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