Magnesium Deficiency in Greenhouse Tomatoes

In a sand culture experiment with greenhouse tomatoes, tissue analysis of plant samples showing a wide range of magnesium deficiency symptoms indicated that a tissue level of 0.30% Mg was associated with incipient deficiency and the beginning of symptom expression, while a level of 0.15% or less was associated with severe deficiency symptoms. These are definite values and it is suggested that they may be applicable to many crop plants, provided adequate sampling and accurate analyses are carried out.