C. Sonneveld, S.S. de Bes
The validities of K and Ca levels in plant digests and plant saps, as indices of the nutritional status of plants, were compared. For this purpose tomato was grown on nutrient solutions with different K and Ca concentrations and in different seasons to obtain material with divergent dry-matter contents. Tissue samples were gathered and analysed for K and Ca after digestion of dried material or after acquiring plant sap.

The analytical data show that for K, more than for Ca, the degree of correlation between the results obtained with the two extraction methods depends on the dry-matter content of the fresh material sampled. For K it is demonstrated that analytical data should preferably be obtained with the use of plant sap.

Sonneveld, C. and de Bes, S.S. (1988). INTERPRETATION OF ANALYTICAL DATA OF TISSUE TESTS. Acta Hortic. 222, 147-154
DOI: 10.17660/ActaHortic.1988.222.17

Acta Horticulturae