Influence of Temperature on the Yield and Chemical Composition of Five Forage Legume Species1

Abstract

AbstractOne‐year‐old plants of ‘Vernal’ alfalfa, ‘Lakeland’ red clover, ‘Common’ alsike clover, ‘Empire’ birdsfoot trefoil, and ‘Goldtop’ biennial sweetclover were grown to first flower in four temperature regimes: (a) 32 C, day/27 C night, (b) 27/21 C, (c) 21/15 C, and (d) 15/10 C. Flowering was delayed as temperatures decreased, except for trefoil and sweetclover where flowering occurred first in (b). Herbage, root, and total plant dry matter yields increased as temperatures decreased, except for trefoil in (a) where maturity was delayed and yields were as large as in (d). Average shoot height of red and alsike clovers and sweetclover increased as temperatures decreased, but changed little with trefoil. Shoot height of alfalfa was greatest in (b). Numbers of shoots were not affected by temperature, except in alsike clover where they increased as temperature decreased. Influence of temperature on chemical composition of the herbage and on carbohydrate storage in the roots is discussed. It was noteworthy that K concentration was very low in the herbage grown at the coldest temperatures (d) where the average for all species was 1.4% as compared with 2.3% in the herbage from (b).