PERFORMANCE OF ALFALFA IN INDIANA, 1993-1996

BULLETIN NO. B739, Department of Agronomy
Purdue University, W. Lafayette, IN 47907-1150
Authors: Miles E. Kuhn and Keith D. Johnson

Introduction

This bulletin summarizes the results of 1993-1996 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:

Additional copies of this publication are available to Indiana residents from their local Purdue Cooperative Extension Offices or by writing:

Media Distribution Center
301 South 2nd Street
Lafayette, IN 47905-1092

This document can also be accessed electronically by sending email to almanac@ecn.purdue.edu and in the body of the message type:
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Acknowledgements

We appreciate the help of the personnel of the regional Purdue Agricultural Centers, the Agronomy Research Center, and the many student and temporary workers that have assisted in these studies. We would like to thank the National Weather Service for the data used in Appendix Figure 1 and Appendix Table 2. We would also like to thank the Indiana Agricultural Statistics Service for the information included in Appendix Table 1 of this bulletin. A special thanks goes to Lou Jones, our departmental artist. Much of the artwork that brightens our bulletin is from her pen.

The 1993-1996 Growing Season

Rain fell frequently in 1993 as the state's first harvest approached, delaying harvest at Columbia City until June 10. In order to maintain a reasonable harvest schedule, watching for breaks in the weather became a high priority. While moisture and forage growth were plentiful in 1993, hay drying conditions were poor for most of the year. Quality of much hay suffered from rain damage as time frames of more than a few days of sunshine were rare.

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 study seeded in 1993 at Butlerville had to be abandoned this spring due to heaving in excess of six inches. Plentiful rainfall at Butlerville provided for above average yields on the 1995 seeded study.

Experimental Methods

Participating seed companies selected entries to be tested. Seed was sent to Purdue University for planting and evaluation. Beginning in 1994, commercial entries were obtained through a seed procurement program initiated by recommendation of the North American Alfalfa Improvement Conference. Experimental entries (i.e. experimental generations) from companies sent to Purdue were accepted into yield tests, with data to be clearly marked as from a non-commercial entry.

Between 1993 and 1996, Purdue University successfully established ten alfalfa performance trials at four 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) and dimethoate (Cygon), respectively. When necessary, control of broadleaf or grass weeds was accomplished with application of 2,4D-B (Butyrac), sethoxydim (Poast) and 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.

Presentation and Interpretation of Results

Yields are reported as dry matter yield in tons per acre (T/A). Tables 1-9 summarize results of 1993 - 1996 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 1-9. The check variety used was Vernal. Additionally, Tables 1 and 5 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 1994-1996 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.

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.

Location of Performance Trials

The following is information about each location.

The Pinney Purdue Agricultural Center is located near Wanatah in Porter and LaPorte Counties (Jon D. Leuck, superintendent). Studies seeded in 1994 and 1995 (Tables 2 and 3) are on a Sebawa loam soil on a 0-2% slope, formed in loamy glacial outwash. The 1993 seeded study (Table 1) is on a Tracy sandy loam on a 0-2% slope and was irrigated when needed.

The Northeast Purdue Agricultural Center is located near Columbia City in Whitley County (Philip C. Walker, superintendent). The 1994 (Table 4) wes conducted on a Rawson sandy loam on a 2-6% slope.

The Purdue Agronomy Research Center is located near West Lafayette in Tippecanoe County (James J. Beaty III, superintendent). The 1993 study (Table 5) was conducted on a Chalmers silt loam (0-2 % slope). A Drummer silt loam with a 0-2% slope and a 4-5% organic matter content is the site of the 1994 and 1995 seeded trials (Tables 6 and 7). Both are highly-productive, prairie-derived soils. The 1996 seeded study (Table 8) was conducted on a Xenia silt loam soil with a 0-2% slope.

The Southeast Purdue Agricultural Center is located near Butlerville in Jennings County (Donald J. Biehle, superintendent). The 1995 seeded study (Table 9) is on an Avonburg silt loam soil with a 0-2% slope.

Hay statistics for Indiana and the United States

¹ December 1996 estimates
² Does not include yield harvested by grazing or removed as silage.