A new statistical approach for the interpretation of nutrient interrelationships. IV. Boron/Iron

Abstract

Sunflower plants 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 times. Dry weight, and N, P, K, Ca, Mg, Fe, Cu, Mn, Zn, and B concentration 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 developed 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. Iron uptake is considerably influenced by Zn (15%) and B (80%). While Fe influences both ions with 24% for Zn and 66% for B. Iron transport is affected by K (28%), Cu (2%), and B (55%), all of which participate in the energetic processes and in the protein syntheses, while Fe influences positively in Mn transport with 4%. In the whole plant, the Fe transport is favoured by Zn (18%), Cu (39%), and B (33%), and it influences negatively on the dry weight (29%), and positively with Cu (43%) and B (30%).