Morphological and Physiological Factors Related to Yield of Alfalfa

Authors

A. L. Foutz
Wallace Wilhelm, University of Nebraska-LincolnFollow
A. K. Dobrenz

Date of this Version

November 1973

Comments

Published by AMERICAN SOCIETY OF AGRONOMY.

Abstract

Several morphological and physiological factors were measured on clones of alfalfa (Medicago sativa L. ‘Mesa- Sirsa’) which displayed a wide range in SLW, leaflet weight and leaflet area. Apparent photosynthesis, dark respiration and post-illumination burst expressed as mg C0₂ dm^-2hr^-1 were not related to yield. However, when the rate of each factor was expressed on a whole plant basis (rate x leaf area per plant) , significant relationships were found with yield. Correlation coefficients between total apparent photosynthesis, total dark respiration, total post-illumination C0₂ burst and yield were r = .71*, r = .77* and r = .80*, respectively. Regression analysis showed that leaflet to stem petiole ratio, total leaflet area and percentage leaflets accounted for over 98% of the variation in yield.