Julie Hansen, Don Viands, Department of Plant Breeding and Genetics, Cornell University
October 23, 2012
Each spring, over 100 varieties of forages are planted in replicated plot trials in New York State. One alfalfa trial is planted in Ithaca (Cornell University Agricultural Experiment Station, South Central) and one trial is planted in a rotation at either Western New York, Eastern New York (SUNY Cobleskill), or Northern New York (William H. Miner Agricultural Research Institute, Chazy). Other forages (red clover, birdsfoot trefoil and grasses) are planted at Ithaca. Each trial has from about 5 to 50 varieties in it and the trials are managed for four years. Variety yield (tons / acre) and plant survival (%) are available on the web: http://plbrgen.cals.cornell.edu/cals/pbg/programs/departmental/forage/
Results for 2012 growing season will be available at this website in early November, so before selecting forage varieties to plant in 2013, check the trial results.
Alfalfa varieties differ in characteristics such as fall dormancy, disease resistance, resistance to potato leafhopper, enhanced forage quality, hybrid genetics, roundup ready, and other characteristics. Generally, yield is a main selection criterion for alfalfa varieties. For the six production-year trials harvested in 2011, the average difference between the highest yielding variety in a trial and the lowest yielding variety in a trial was 1.25 tons per acre dry matter.
Alfalfa varieties with high yields in the trials are generally well adapted to New York and are resistant to at least three diseases: Bacterial Wilt, Verticillium Wilt and Phytophthora root rot. From the results of a trial, several high yielding varieties are identified, not just one variety. Also, look for varieties that yield well in several trials over years, not just one trial. In 2011, for the varieties that were in the top 50% of one or more of the six trials in New York, 5 varieties had a fall dormancy rating of 3 (dormant), 20 varieties had a fall dormancy rating of 4 (moderately dormant), and 3 varieties had a fall dormancy rating of 5. Fall dormancy is a rating of variety’s response to shorter days and lower temperatures, and a higher number means that the plants will grow more into the fall. Varieties that are less fall dormant (have a fall dormancy rating that is a higher number) may not be able to withstand winters over multiple years.
The 2012 report will contain yields of many forage varieties and their performance over several years and trials in New York. Be sure to look over the trial results prior to purchasing seed for 2013.
