RELATIONSHIP BETWEEN THE NUTRITIONAL STATUS OF MINISTUMPS TO THE ROOTING OF EUCALYPT MINICUTTINGS

The adventitious rooting of cuttings is influenced by intrinsic and extrinsic factors of the plant material. The knowledge about the action mode of these factors upon rooting is fundamental for the successful production of clonal seedlings through minicuttings. The objective of this study was to evaluate the degree of association between the nutritional state of ministumps with the rooting of eucalypt minicuttings, grown in a clonal minigarden in tubes with subirrigation. Data from minicutting rooting and nutrient contents quantified by chemical analyses of the leaf tissues were used. The rooting rate was correlated with the nutritional status of the shoots. It was verified that mineral nutrition plays an important role in adventitious rooting in a genotype-dependent way, i.e, the performance of the clones differs in relation to the effect of nutrients on minicutting rooting. For potassium, calcium, magnesium and manganese no association was observed between nutrient contents and the shooting and the rooting rates. For the other nutrients, at least for one clone, there is a positive or negative association among the variables, and the degree of this association varies according to the clone and nutrient.