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THIS is the fourth consecutive year that I have reported the results of our own maize trials that have been conducted throughout the south west region, this year being one month later than usual due to the late harvest in some cases.

April proved to be exceptionally warm and dry and consequently, a lot of maize was drilled up to a fortnight earlier than the norm and we could have been forgiven for thinking that we were in for another really good year - but how wrong we would have been!

May, June, July and August gave us four months of pretty abysmal weather which meant that maize on anything other than the most favourable sites really did struggle, and just to make sure that we knew who was really in charge, nature sent along just a few cases of eyespot to boot!

A two-month Indian summer helped enormously with October proving to be the harvesting month. With drilling being up to two weeks earlier than last year and harvesting being two to three weeks later, you could quite easily argue that there was at least one month's difference between the two years.

Eyespot did prove to be a problem throughout the region - especially on sites that were exposed to the prevailing winds. As the season progressed, it soon became obvious that there were varietal differences, but contrary to a report that appeared in last month's South West Farmer, our findings, along with previous years, seem to suggest that in most cases, it was the late varieties that appeared to suffer the least.

At the Cornwall Farmers Site, Tregony, near Truro, sixteen varieties were drilled on May 2 at 42,500 seeds per acre and harvested on October 19, overall being two weeks later than last year. Ten varieties had been singed with eyespot, Kokum and Karimbo had severe infections, Kullas, Kadenz and Kangaroo were mainly clear with just one variety, Katy, being eyespot-free. Eight varieties recorded dry matters of 30 per cent or more with Destiny the highest at 34.43 per cent, closely followed by Crown at 34.06 per cent, with Kadenz and Huski being the lowest at 20.46per cent and 24.64 per cent respectively. Nine varieties had starch levels in excess of 30 per cent with Revolver being the highest at 38.87per cent followed by Sapphire at 35.73per cent. The two lowest were Kadenz at 21.23 per cent and Huski at 22.67 per cent. Adept really did distinguish itself by recording the highest dry matter and starch yields.

At the Mole Valley Farmers site, Newquay, twenty varieties were drilled on April 14 at 42,500 seeds per acre with fifteen being taken to harvest on October 1, only four of which recorded dry matters in excess of 30 per cent. The highest was Acclaim at 32.73 per cent, followed by Kingdom, Toccata and Revolver. The two lowest were Energystar at 20.33 per cent and Oxaya at 21.06 per cent. Yet again, only four varieties achieved starch levels of 30 per cent or more with Acclaim recording the highest at 36.41 per cent, followed by Kingdom, Toccata and Kroesus - the two lowest being Oxaya at 6.41per cent and Agreement at 19.13 per cent. Toccata recorded the highest DM yield with Acclaim the highest starch yield.

The Cornwall Farmers site at Ilfracombe, north Devon is, at 740ft, an extremely marginal site - and was chosen for that very reason. We wanted a site that would tax even the best material on offer, but even the most sceptical among us never for one moment dreamed how taxing the site and year would prove to be! The whole trial was hit with eyespot, some varieties being more susceptible than others, fresh weights were down as crop height was affected by wind exposure, and full cob maturity was far from being fulfilled.

We did feel that whole plant dry matters had been artificially enhanced by eyespot - the greater the level of infection, the more the dry matter has been affected, so we therefore feel that the starch levels would be a better indicator of how well a particular variety has performed.

Fifteen varieties were drilled on May 19 at 45,000 seeds per acre and harvested on October 23. To give an idea as to how the site and year affected individual varieties, there were only four that yielded in excess of 11 tonnes per acre (Kangaroo, Kullas, Adept and Kadenz) with three varieties (Revolver, Cornstar and MAS 09A) yielding below eight tonnes per acre.

Whole plant DM's, even with the benefit' of eyespot were very low with only 2 varieties (Destiny and Sapphire) being above 20per cent, with Adept, Huski, MAS 09A, Kadenz, Kangaroo and Kullas all being below 15 per cent. Starch levels, in most cases, tended to reflect dry matters - that is, the higher the dry matter, the higher the starch, with Sapphire and Destiny at 16.20 per cent and 14.53 per cent respectively, with only an additional four varieties (Tomahawk, Cornstar, Karimbo and Crescendo) having starch levels of 10 per cent or more. The remaining nine varieties were all in single figures, down to as low as 2.75 per cent.

Sapphire and Destiny recorded the highest DM yields, both being just over two tonnes per acre with Revolver and MAS 09A at just over one tonne per acre.

Sapphire and Destiny also recorded the highest starch yields at 0.34/0.29 tonnes per acre, with only Tomahawk and Karimbo coming close.

It is impossible to argue that anything did well on this site, the only conclusions being that some varieties really struggle on a marginal site in a marginal year, despite the fact that they are perceived as being very early. We are proposing to use the same farm again in 2008 - again with very early material - but because of the severe eyespot infection, we will have to take another field.

At the Mole Valley Farmers site, Bridgwater, 22 varieties were drilled on April 25 with 14 being harvested on October 3. Eight were discarded as being unsuitable. Everything had been singed with eyespot with Revolver being the only variety where all the leaves were dead, with a subsequent influence on dry matter at 37.7 per cent, followed by Challice at 28.61 per cent and Toccata at 27.86 per cent. Kingdom recorded the highest starch levels at 36.42 per cent, with Toccata and Challice at 35.68 per cent and 35.03 per cent respectively. Although Revolver recorded the highest DM percentage, its starch levels came in at 26.23 per cent.

Aurelia and Challice recorded the highest DM yields, with Toccata and Challice the highest starch yields.

This is a most favourable site situated on the Bridgwater levels, but above-average summer rainfall dictated an earlier harvest, otherwise machinery would quite literally sink! Interestingly, although cob maturity was just about right (as seen by starch levels), whole plant dry matters were quite low due to very wet stovers.

Three Pearce Seeds sites in Dorset were used this year - two marginal and one favourable, with all three recording dry matter and starch levels down against 2006 and 2005.

Robert Baker, the maize trials officer with Pearce Seeds, reports that Destiny was the most consistent performer across all three sites, followed closely by Sapphire with the new variety Beacon recording high yields. 1xx's, in addition to being early, also performed well. A lot of material was used in the three trials, some new and some of which were NIAB-recommended, but a significant proportion was adversely affected by the difficult growing conditions.

"An interesting trialling year which has sorted quite a lot of wood from the trees,'' reports Robert.