Nine varieties come recommended on the 2018 department forage maize list. And, as was the case last year, two of these are new and provisionally recommended for the first time. These are P8201 and Spyci CS. Galbi CS and Justina have been discontinued.

The list of recommended varieties for planting under plastic in 2018 is shown in Table 1. The recommended list is compiled from information from a number of sites in the three most recent years.

While there will still be some maize sown in the open in highly favourable areas, most will be sown under plastic. Plastic helps make crops mature earlier but later varieties tend to be sown and the plastic itself adds to the cost.

Growers should be conscious that plastic is not a guarantee of performance and is not an insurance against poor husbandry. The recommended varieties have had to perform consistently well for at least three years to earn this status and that provides a badge of reliability to growers.

However, a late-maturing variety sown late in a late region is unlikely to deliver quality maize silage in some years. Variety choice must always be a compromise between yield potential and the suitability of your site to deliver the required quality.

Relative variety ratings and actual yield data for the mean of the control varieties are shown in Table 1. This also gives the relative ratings of all varieties for a range of characteristics relative to the controls, which were different in different years.

The DM rating in the right-hand column gives growers a clear indication of the suitability of a variety for different sites. The lower the DM value, the more important it is to have early planting on a favourable site. High dry matter is a good indicator of how much the crop has matured prior to harvest.

Details of the 2018 list

There are now recommended varieties to meet the requirements of all maize growers. The Maize Growers Guide published last year recommends that: “Growers should only select the varieties listed because these varieties have been independently and robustly tested by DAFM over a minimum of three years under Irish conditions and have been proven to perform in these conditions.”

Characteristics of the varieties

Ambition (R): Remains the lowest-yielding variety on the list but it has the highest starch content. It has extremely high dry matter content and is very early maturing. It is suitable for late sowing and/or early harvest, particularly on less favourable sites. Bred by Limagrain Verneuil Holding in France and handled here by Goldcrop Ltd.

Award (R): Good yield potential with good starch and dry matter content. It is an early-medium maturing variety. Might be described as a safe variety that has been recommended since 2011. Bred by Limagrain Advanta Nederland BV in The Netherlands and handled here by Goldcrop.

Grosso (R): Good yield potential with good starch content. It has moderate dry matter content and is medium-late maturing. More suited for early sowing in favourable sites than in unfavourable sites. It was bred by KWS Saat in Germany and is handled here by DLF Seeds.

LG30211 (R): Another good-yielding variety with high starch content. Dry matter content is good and is medium maturing. Suited to sowing in most situations. Bred by Limagrain Verneuil Holding in France and handled here by DLF Seeds.

P7905 (R): A high-yielding variety with good starch content. It has moderate dry matter content and is medium-late maturing. More suited to early sowing in favourable sites. Bred and handled by DuPont Pioneer.

P8200 (R): Fully recommended this year. It is very high-yielding but low in starch. It has moderate dry matter content and is a medium-late maturing variety. More suited to early sowing in favourable sites. Bred and handled by DuPont Pioneer.

P8201 (PR-1): New with a provisional recommendation in 2018. It is the highest yielding variety on the list and couples high yield with high starch content. Dry matter content is moderate so it is medium-late maturing. More suited for early sowing in favourable sites. Bred and handled by DuPont Pioneer.

Spyci CS (PR-1): New on the list for 2018 with a provisional recommendation. It combines good yield and high starch content. Dry matter content is good and it is rated early-medium maturing. It was bred by Caussade Semences and is handled here by Goldcrop Ltd.

SY Feeditop (R): Good yield potential with very high starch content. It has high dry matter content and is early-medium maturing. Bred by Syngenta and handled here by Goldcrop Ltd.

Varieties tested in 2017

Many other varieties are being tested. A list of these is shown in Appendix 1 of the recommended list and includes some that have not yet been recommended and may never be but they are being evaluated. Some of these varieties are already recommended while others were only tested for the first time in 2017. Some varieties tested in 2016 were not continued in 2017 and others came in for testing.

Uncovered performance list

Testing of varieties for planting in the open discontinued in 2015 so there is no longer a recommended list for this use. While details of the 2015 list are shown in Appendix 2 of the recommended list, growers considering planting in the open should consult with their seed agent as they still do some limited testing of newer varieties for this system.