Developing a Standard test for Lodging Resistance in Alfalfa for North America
Developing a Standard test for Lodging Resistance in Alfalfa for North America
Debra Sharpee, Gary Hoard, Mark Smith, Dave Miller
Pioneer Hi-Bred International Inc.
Introduction
• Lodging resistance (LR) or standability is an important trait in many crops.
• Improved LR often results in increased harvestable yield and crop quality.
Introduction
• Alfalfa has been improved for LR primarily in germplasm adapted to France.
• French varieties must meet minimum standards for LR to be eligible for inscription.
• Testing for LR in France is based on observations prior to cutting, and on stubble after cutting.
Introduction
• Varieties with improved LR are beginning to be marketed in North America.
• There is a need to describe LR in North American adapted varieties for purposes of variety description.
Objectives
• Examine the relationship between LR in solid-seeded plots vs. spaced planted alfalfa.
• Develop criteria for evaluating individual plants for lodging resistance.
• Take the first step in developing a standard test for LR in North America.
Experimental Procedure
• Establish solid seeded yield plots (~1m x 4m) with LR varieties and commercial varieties in spring 2001.
• Transplant 100 plants (4 reps, 25 plants/rep) of same varieties in spring 2001.
• Allow both trials to grow until commercial varieties are obviously lodged and score in Johnston, IA and Arlington, WI in spring 2002.
Experimental Procedure
• Score plots on a 1-9 scale where 9 = no lodging and 1 = completely lodged.
• Score each plant in transplanted test and determine a Percent Resistant Plants (PRP) to lodging.
Experimental Procedure
• Spaced plant scoring criteria:– 9=Erect, plants instantly spring back
to vertical.
– 7=Mostly erect, but leans some.
– 5=Plant leans ~45 degrees.
– 3=Plant leans more than 45 degrees.
– 1=Plant flat on ground.
Results
Variety Plots-IA Plots-WI
PRP-JH PRP-WI
Europe 9.0 7.5 50 44Exp A 6.3 7.0 65 76Exp B 5.8 4.0 30 2354H91 4.3 2.5 0 454V54 1.8 1.5 1 7Geneva 1.0 1.0 1 4LSD(.05) 1.6 1.8 14 14
Plots= whole plot scores; PRP based on classes 7-9
Discussion
• There is a clear relationship for LR between solid-seeded and spaced planted tests.
• The spaced plant scoring criteria was useful for describing solid-seeded performance.
Discussion
• Progress on developing a standard test:– Good “first-step” in developing
scoring criteria.
– Europe (French variety) is a candidate for an HR check.
– Several candidates for lodging susceptible check (eg. 54V54, Geneva).
Discussion
• Additional data has shown that LR in seeded plots is very consistent across cuts, locations, and years.