Missouri corn variety test yields spotty

COLUMBIA, Mo. – Timely planting played a large part in corn yields listed in the 2015 University of Missouri Variety Testing Program report released at the end of October.

“This was a year of highs and lows,” said Howard Mason, MU Extension research associate.

Too much rain plagued farmers during planting season, delaying or preventing planting and application of weed control chemicals. Then drought occurred during critical growing times, Mason said.

Most test fields were planted timely, but three central Missouri fields, two fields in southwestern Missouri and one in northern Missouri were abandoned due to sparse and uneven stands.

Planting date, more than irrigation, affected yields in the state’s four corn-growing regions, Mason noted. “Even with irrigation, planting date made a difference of almost 60 bushels per acre,” he said.

A six-year research project by MU Extension agronomist Bill Wiebold shows that corn planted on or after June 1 in central Missouri yields 22 percent less than corn planted on the optimum date. Wiebold’s research also shows temperature and precipitation in July and August affect yield more than planting date.

Grand mean yields in northern Missouri, where fields are not irrigated, topped 202.9 bushels per acre this year. Fields there were planted April 22-29. Yields in 2014 were 200 bushels per acre.

Mean yields topped the 223.5 bushel per acre mark at test plots in southeastern Missouri. Last year’s grand mean was 279.2 bushels per acre. Loam fields were planted at month’s end in April while one clay field was not planted until June 4.

Irrigated fields in the southwestern region grew a grand mean of 169.4 bushels per acre. Nonirrigated fields showed 140.6 bushels per acre. Irrigated loam soil fields in Garden City were planted May 1 and saw yields some 60 bushels per acre higher than fields in Adrian, which weren’t planted until June 9.

Nonirrigated fields in the central region showed 202.6 bushels per acre while irrigated fields registered 176.4 bushels per acre.

The Division of Plant Sciences in the MU College of Agriculture, Food and Natural Resources has conducted the variety-testing program for more than 75 years. Since 1973, seed companies and groups have chosen several of their best hybrid varieties for evaluation at farmer-owned fields and MU test plots throughout the state. MU researchers publish unbiased results online and in a booklet.

More than 195 hybrid varieties were tested this year.

Wiebold said the United States Department of Agriculture reported on Oct. 28 that the Missouri corn harvest, at 94 percent complete, is 27 percentage points ahead of last year at this time. USDA reported corn prices at $3.67 per bushel, slightly higher than this time last year, when prices were $3.46 per bushel.

Wiebold said hybrid performance might seem inconsistent from location to location each year. Producers should consider annual differences, including rainfall, diseases, insects and other factors. There are other considerations besides yield when selecting a corn hybrid. Carefully consider stalk strength, maturity and resistance to insects and disease, he said.

For updated information, go to http://varietytesting.missouri.edu/corn/.