This bulletin summar-izes the results of 1994-1997 yield performance tests of alfalfa variety entries in Indiana. This information, protected by copyright by the Purdue Research Foundation, is presented under authority granted the Indiana Agricultural Research Programs to conduct performance trials, including interpretation of the data to the public, and does not imply endorsement or recommendation by Purdue University. Permission is granted to reproduce the tables only in their entirety provided the source is referenced and the data are not rearranged, manipulated, or reinterpreted. A conspicuous disclaimer which states "endorsement or recommendation by Purdue University is not implied" must accompany any information reproduced. Additional copies of this and other informative publications are available to Indiana residents from their local Purdue Cooperative Extension Service Office or by writing:

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Between 1994 and 1997, Purdue University successfully established twelve alfalfa performance trials at five locations across Indiana. Test plots were seeded into conventionally prepared seedbeds. Benefin (Balan) herbicide was incorporated into the soil prior to seeding. Seed was inoculated with Rhizobium bacteria and treated with metalaxyl (Apron) fungicide. Plots were seeded with a five-row press-wheel seeder with 6-inch row spacings.

Best management practices were administered to all studies. Optimum pH and fertility were provided and maintained. Alfalfa weevil and potato leafhopper were controlled with the systemic insecticides carbofuran (Furadan), Bathyorid, and dimethoate (Cygon), respectively. When necessary, control of broadleaf or grass weeds was accomplished with application of 2,4D-B (Butyrac), sethoxydim (Poast) and/or imazethapyr (Pursuit) herbicides, respectively. Winter-annual weeds were controlled on new and established stands with an application of pronamide (Kerb) and metribuzin (Sencor) herbicides, respectively. A flail-type forage harvester was used to harvest plots, generally in late-bud to early-flower stage. Hand samples were utilized for dry matter determination.

(Refer to precipitation charts and average daily temperature deviation table for more information.)
West Lafayette
Wanatah
Bedford
Buttlerville
Columbia City

The winter of 1993-1994 was especially hard on alfalfa stands in the southern part of the state. Stands were reduced by half due to heaving and winter injury. Drought stress worsened yields throughout the summer at Butlerville. Pockets of drought plagued much of the state throughout the season, and lowered Indiana hay supplies. First harvest was taken at a mid-bud stage during a week of exceptionally good harvest weather.

Early season rain in 1995 resulted in higher yields for the first harvest across the state. Butlerville maintained an adequate amount of soil moisture for the entire growing season. Lack of mid-summer moisture and excessive heat limited growth at West Lafayette, while Wanatah and Columbia City were less affected. Late-summer moisture fell statewide, permitting alfalfa to enter the winter in good shape.

Early season rain in 1996 made it difficult to establish alfalfa stands as well as delaying most of the first cutting across the state. Due to this delay, the two northern sites only reported three harvests for the year. Lack of moisture at West Lafayette caused a decrease in yield toward the end of the season.

The 1997 growing season started out positive with the plots timely planted, giving the seedlings a good start. This year progressed with the central and southern sites going from very wet to dry; and the southern sites becoming very dry. Along with the variation in moisture in the state, the temperatures remained unusually cool causing the growing degree day totals to be two weeks behind normal. This reduced the growth and lengthened the time between harvests. Due to these factors, the reseeded plots at Bedford and the new seeding at Wanatah could only be harvested one time. With timely rains this fall the studies entered the winter in good condition.

Yields are reported as dry matter yield in tons per acre (T/A). Tables (1-12) summarize results of 1994-1997 alfalfa variety yield trials conducted in Indiana.

In each table, varieties are listed in order of total yield to date. Within a column, varieties differing from each other by less than the respective LSD (least significant difference) were not significantly (probability > 0.05) different. Yields followed by an asterisk (*) are not significantly different from the highest value in the column.

The CV (coefficient of variability) is the ratio of the standard deviation to the grand mean. It is used as a measure of the precision of the experiment. Lower CV's indicate lower experimental error in the trial.

Number of harvests within a year is listed at the bottom of each yield column.

Yield as percent of check is listed in the rightmost columns of Tables (1-12). The check variety used was Vernal. Additionally, Tables (1-6) show percent of check in the first two years and in the final two years of production. This can be used as a measure of persistence. Percentages that increase with time or are relatively high in the final years may be an indication of better persistence.

In 1994, the North American Alfalfa Improvement Conference recommended new guidelines to separate entries allocated from commercial and experimental seed sources. In the presentation of the 1994-1997 seeded studies, names of entries are preceded by "x" if tested using experimental seed provided by the entrant; remaining entries were obtained from commercial seed lots. Research has shown yield tends to decrease in some breeding lines as seed progresses from a more heterozygous state in experimental generations to the commercially available generation.

Information presented in the bulletin should be useful in selecting alfalfa seed for forage production in Indiana. Here are some suggestions for using this information.

1. Select the test location (Figure 1) that best represents your production area.

2. Within a location, yield tables with the greatest number of years are probably the best predictors of performance.

3. Utilize the percent of check columns in Tables 1 thru 6 to evaluate persistence.

4. If a particular disease problem is known in your area, check Appendix Table 3 for resistance ratings. Fall dormancy ratings of 2-4 are generally appropriate for northern Indiana and can be as high as 5 in the southern part of the state.

5. Once your list is narrowed down, call or write seed dealers listed in Appendix Table 4 for seed availability and price.

Appendix Table 3 contains a listing of commercially available entries, reference number of their marketer(s)(in correspondence with Appendix Table 4), tables where data is found, and characterization information including fall dormancy rating and resistance rating to bacterial wilt, verticillium wilt, fusarium wilt, anthracnose, phytophthora root rot, stem nematode, and root-knot nematode.

Appendix Table 4 lists marketer, address, phone number, and contact person as provided by the entrant company and referenced in Appendix Table 3.