Since maize is still a fairly new crop in Ireland, the Crop Variety Testing Division is testing varieties on a continual basis for their suitability in Ireland. Some varieties are on the List of Recommendation, which is drawn up by the Department of Agriculture and Food. Such varieties have completed a trial for a minimum of three years on farms selected by the Department. They are situated in locations considered to be suitable as well as unsuitable for the production of maize. Counties include: Cork, Waterford, Wicklow, Tipperary, Meath, Louth, Kilkenny, and Kildare. Trials are sown in late April to early March without the use of plastic.
The new varieties are then submitted to the Department to be entered into screening trials. This involves the growth of 20 varieties by the Department at two centres, where they are assessed for at least two years. The varieties are assessed on the basis of dry matter yield, dry matter content, starch content and other characteristics. The 15 most successful varieties are then advanced to the National Recommended List Trials where they are assessed again for three years at six different centres.
After this period, the new varieties, which show a superior performance, are given a positive Value for Cultivation and Use status. These are then included on a National List, which allows them to be considered for a Provisional Recommendation, and if they continue to perform well for approximately three years they are upgraded to Full Recommendation.
The Department of Agriculture and Food takes whole crop samples from each farm that has been selected for the trials and dries them to determine the dry matter content of each sample. The starch content, which is expressed as a percentage of dry matter, is also determined. The tests are carried out by F.B.A. Laboratories Ltd., Fermoy, Co. Cork.
Varieties that are on the Recommended List for growing under plastic have been chosen because of their ability to break through the plastic well, e.g. Algans, Andante, Hudson and Justina.
Varieties that are on the Recommended List for growing on uncovered ground include those listed in the section 'Varieties of Maize'.