Open AccessMAGNESIUM DEFICIENCY IN LUCERNE
Author(s) -
M. R. J. Toxopeus,
K. J. McNaught
Publication year - 1972
Publication title -
proceedings of the new zealand grassland association
Language(s) - English
Resource type - Journals
eISSN - 1179-4577
pISSN - 0369-3902
DOI - 10.33584/jnzg.1972.34.1325
Subject(s) - chlorosis , magnesium , agronomy , topsoil , magnesium deficiency (plants) , yield (engineering) , horticulture , zoology , biology , chemistry , soil water , metallurgy , materials science , ecology , organic chemistry
An experiment was conducted on lucerne (cv. Wairau), growing on a yellow-brown pumice soil low in magnesium. Under a regime of four harvests annually, small but sign&cant yield responses of 4 and 5% were obtained in the third year to additions of 17 and 34 kg/ha Mg, respectively, when the topsoil (0 to 7.5 cm) Mg value in the control plots had fallen to 2 units (advisory scale). Responses were associated with a concentration of 0.09% Mg in herbage cut ,at the onset of flowering. Foliar symptoms of magnesium deficiency were a chlorosis which increased in severity towards the base of the plant.