Alfalfa varieties for biomass production. Task IId. Quarterly report, July 1, 1997--September 30, 1997

摘要

The use of alfalfa for biomass production may require harvest schedules and alfalfa varieties with different traits than currently marketed varieties. A late flower (2-cut) system may have several advantages compared to more frequent cutting systems because it can result in high stem yield, result in less trips over the field, allow more schedule flexibility, provide greater wildlife habitat, and allow greater alfalfa persistence. However, modem alfalfa varieties have been developed for a frequent harvest system with 3-4 cuttings per season. The objectives of this study were to determine the total biomass yield; leaf and stem biomass yield; and leaf and stem composition of alfalfa varieties subject to diverse harvest regimes. Alfalfa varieties included those currently marketed in the biomass region as well as experimental entries developed for lodging resistance and leaf retention. Harvest regimes included conventional strategies based on harvests at bud or first flower and a non-conventional strategy with harvests at late flower. Harvest regime had the most consistent and greatest effect on the variables studied. Forage yields were greater for the early flower regime. Harvests at earlier maturity frequently result in leafier, higher quality forage than harvest at late flower. 3 figs., 9 tabs.