Submitted to: ASA-CSSA-SSSA Annual Meeting Abstracts
Publication Type: Abstract only
Publication Acceptance Date: 5/3/2004
Publication Date: 10/31/2004
Citation: Casler, M.D. 2004. Forage yield improvements: mirages and realities [abstract] ASA-CSSA-SSSA Annual Meeting Abstracts. Paper No. 4379. Interpretive Summary:
Technical Abstract: Improvements in forage yield have lagged significantly behind those for grain yield. During the latter half of the 20th Century, forage yield increased by 3-5% per decade, while grain yield increased by 8-21% per decade. The superior rate of progress for grain yield compared to forage yield can be attributed to (1) a shorter breeding cycle compared to perennial forage crops, (2) exploitation of an increased harvest index, (3) exploitation of heterosis for grain yield, and (4) dedicated and focused attention on grain yield per se. The perenniality of forage crops and the need for persistence demands a minimum of 2-3 years of field evaluation within each selection cycle. The harvest index concept of grain crops has no relevance in forage crops, except when they are in seed multiplication mode. There is significant heterosis for forage yield in many crops, but it has yet to be exploited due to seed production problems and market restrictions. Finally, forage breeders tend to focus their attentions on other traits, such as pest resistance, persistence, and forage quality. Nevertheless, there is sufficient genetic variability to make dramatic improvements in forage yield and imaginative manipulations of planting arrangements, experimental designs, data collection, and breeding methodology can lead to rapid progress and significant improvements in forage yield.