Variety Trials of Selected Farm Crops
Successful crop production depends to a considerable extent on selecting the best varieties for a particular farm. For that reason, varieties are compared in trial plots on Minnesota Agricultural Experiment Station fields at St. Paul, Rosemount, Waseca, Lamberton, Morris, Crookston, Grand Rapids and Becker, and on farmers' fields for some crops. Important old varieties and new varieties are grown in replicated plots at each location. These plots are handled so that the factors affecting yield and other characteristics are as nearly the same for all varieties at each location as is possible.
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Variety Classifications
Interpreting Variety Trial Tables
United States Plant Variety Protection Act
Minnesota Agricultural Experiment Station scientists do not conduct performance trials for every crop every year. The data presented at this "Varietal Trials" web site represents the most recent performance evaluation trials, which for some crops may have been several years ago.
There can be varied reasons for performance evaluations not being conducted in the current year for any specific crop. For some crops there may simply be too few acres growing it in Minnesota to make such trials an appropriate investment of limited fund or staff time. For other crops, there may not be any new varieties being released to be tested. Or, there may simply be no support from any appropriate industry group for conducting current trials. The year of the trial attached to the link on the "Variety Trials" contents page indicates the most recent crop production year for which that crop's trials were conducted.
Variety Classification Definitions
Many crops have their varieties classed into subgroups under the headings such as "recommended public varieties," "special purpose variety," "other varieties," etc. Variety descriptions are arranged alphabetically or by some important growing characteristic, such as maturity date, within groups.
When noted, classifications of varieties as "recommended," "other," etc., are determined each year by the Experiment Station Crop Variety Review Committee. A variety is usually not eligible for the "recommended" group unless it has been better than other varieties in important characteristics in three years of testing.
New varieties from other public experiment stations and private plant breeders, but not sufficiently evaluated by Minnesota's Agricultural Experiment Station scientists, are listed as "varieties not adequately tested." Available information is presented for these varieties, but no conclusions are drawn regarding their suitability for Minnesota conditions.
Listings in an "other varieties" category are usually inferior in one or more characteristics, as demonstrated in comparative tests. Varieties in the "private" category are good performing varieties, on which the MAES does not make recommendations.
Seed of varieties in many crops may be eligible for certification, and the use of certified seed is suggested, wehn available. However, certification does not imply recommendation. Registered and certified seed of varieties described in this report can be purchased from seed dealers or from growers listed in the Minnesota Registered and Certified Seed Directory for 1997 Planting. This annual publication can be obtained without charge from the Minnesota Crop Improvement Association, 1900 Hendon Avenue, St. Paul, MN 55108, or from county extension agents' offices. The information is also available on-line at http://www.rrtrade.org/mcia/.
The LSD (Least Significant Difference) figures listed under the yield columns in the "Variety Trials" tables are statistical measures of variability within the trials. This statistic is used to determine whether the difference between two yields is due to an actual genetic difference in the varieties or to other causes such as soil variability.
If the yield difference between two varieties equals or exceeds the LSD value listed at the bottom of a yield column, then you can reasonably conclude that the higher yielding variety was superior in yield. If the difference is smaller, then the yield difference was probably due to environmental rather than varietal differences. The notation "NS" in a column indicates no significant difference exists for that characteristic.
The Minnesota Agricultural Experiment Station performance trials are not designed for crop (species) comparisons, because the various crops are grown on different fields or with different management. The data should only be used to compare varieties within a table.
The relative maturities of varieties are variously indicated in the tables as date of maturity, heading, or blooming; days to maturity, heading, or blooming; or moisture percentage at harvest.
United States Plant Variety Protection Act
Changes have been recently made to the U.S. Plant Variety Protection Act. As a result, beginning in 1995 varieties receiving their registration have been identified by the code "PVP(94)" in the text descriptions of their characteristics. These varieties may not be sold by a producer, not even to a relative or neighbor, without the express permission of the variety's developer/owner.