The Relationships between the Nutritive Value, Yield and Resistance of Alfalfa Cultivars to Diseases

The relationships between the digestibility of organic matter, the net energy value, the gas production from in vitro incubation of tissue with rumen liquid, the quantity of yield and the resistance of a variety to disease were investigated in nine alfalfa ( Medicago sativa ) cultivars. The digestibility of organic matter and the net energy value of particular varieties were evaluated on the basis of chemical composition and the quantity of gas produced, while the resistance of cultivars to disease was evaluated visually by counting diseased plants. Negative correlations (r = - 0.85; P < 0.01) were recorded between the resistance of a variety to disease and in vitro production of gas and between the resistance of a variety to disease and net energy value of a cultivar (r = -0.78; P < 0.05) while a positive correlation (r = 0.74; P < 0.05) was established between DM yield and the disease resistance of cultivars.