A new statistical approach for the interpretation of nutrient interrelationships. III. Manganese / iron

Abstract

Licopersicon sculentum Mill were grown in a controlled, greenhouse, in plastic pots (25 plants/ pot) containing 25 g of soil and 475 g of quartz sand. Twelve different soils were tested, each one repeated 5 time. Dry weight and N, P, K, Ca, Mg, Fe, Cu, Mn, Zn and B contents were determined separately for shoots and roots.

Further, based on the multiple linear correlation analysis and the determination coefficients (R), a statistical method has been depeloped to select the variable most effective in explaining the variation of the dependent variable, and then the contribution of every selected variable was calculated and expressed as percent.

In roots, Mn defficiency was the cause of variation of the following parameters, considered as actions on Fe uptake: N (23%) and Cu (34%) positively, and K (26%) negatively. In shoots N (39%), Cu (24%) and B (14%) positively, and Mn (13%) negetively. In whole plants N (46%) and B (41%) positively and Mn (3%) negatively. The variations in the others parameters were considered as being secondary actions.

Key words:

• Tomato
• Manganese deficiency
• Mn/Fe
• Nutrients interactions
• Multiple linear correlations