July 4, 2001 | By: Laura Skillman

Every spring the University of Kentucky Agronomy Department establishes a series of variety trials around the state. The trials are conducted in an effort to further information on the latest hybrids to farmers.

These test plots, generally corn, soybeans and wheat, are filled with an assortment of seed hybrids and are evaluated primarily on how they yield during that year. Other information to consider is moisture, stand, lodging and test weight. Information is cataloged and many of the varieties are tested over a period of several years.

"UK is a source of unbiased information available to farmers and county agents in the state," said William Pearce, UK agronomist who conducts the corn trials.

The corn hybrids chosen for testing are those likely to be commercially available the following planting season. There are three separate tests done based on maturity - early, mid and late season.

The majority of corn planted by Kentucky farmers are medium maturing hybrids, Pearce said. Therefore, the majority of the hybrids in the trials are also medium maturing. This year there are 68 medium maturing (113-117 days), 44 early maturing (112 days or earlier) and 10 late maturing (118 days or longer) in the trials.

Each corn hybrid is grown in three replications at each of the seven locations. Pearce suggests farmers look at the two-year location tables (4E-2YR, 5M-2YR, 6L-2YR) in the agronomy department's publication PR-434 for any hybrid being considered for a particular farming operation. That represents seven locations with 42 replications.

He also suggests that farmers look at numerous sources of data to garner their information on variety performance such as county agent data and individual company data. Many companies conduct strip trial tests throughout the state that can provide useful information to the farming community.

"One thing about all of it is you have to be consistent and fair to the companies and their products," he said.

For 2001, seven sites are selected for corn and five for soybean variety performance trials with the plots being rotated every fourth year.

An important step in profitable soybean production is selecting good quality seed of the best varieties for your management system, said Eugene Lacefield, UK soybean variety tester. Performance of a variety across a period of years and at several locations in the state is the best indicator of its production potential.

This year there are six soybean tests in five locations with 27 conventional varieties and 124 Roundup Ready varieties in the studies. In addition, there are 19 novel soybean varieties, value-added such as natto, high protein and tofu types and 11 public varieties, ones put out by state soybean breeders.

Soybean varieties have been seeing a half bushel per acre yield increase annually and to keep on the cutting edge every few years a farmer needs to change varieties, he said.

By looking at the performance test information, a farmer can select a variety that may be yielding one bushel more than another and over a 500-acre field, that can amount to substantial economic differences, Lacefield noted.

Yield is the primary factor but not the only measure of a variety, he said. Other factors include maturity, lodging resistance, and disease resistance. The economic management and control of weeds are additional factors to consider with the advent of Roundup Ready soybeans.

The most important thing about the UK test plots is that it is a way to evaluate as accurately as possible different corn hybrids in different conditions and different soil types, said Lincoln Martin, Fulton County extension agent for agriculture and natural resources. Corn variety trials are being conducted in Fulton County this year.

Lacefield said he believes the summary table that outlines how a variety did across the various test sites is the best information for farmers to review. The information from individual sites is more limited and more likely to be impacted by factors such as weather and management.


Eugene Lacefield, (859) 257-1825; William Pearce, (859) 257-1874