Active and total Fe in castanea sativa and their relation to other nutrients

Abstract

The concept of active Fe has been seldom applied to the extractable fraction to study its changes through time. Neither its relationships to physiological balance of Fe Index in plants has been investigated to any extent.

The study reported here was conducted on Castanea sativa Miller trees, autoctonous, not grown by man, as the relationships il‐plant is better balanced.

In this work we studied the contents and changes of P, K, Fe, Mn and Zn which are found in extractable form in leaves, the balances of Fe‐Mn‐Zn, and the Fe Index obtained from data of the extractable fraction and their changes throughout the vegetative cycle. The data obtained were related to those obtained from the analysis of the total plant to study their significance in the foliar analysis values, and the possibility to diagnose Fe disorders from balances Fe‐Mn‐Zn and Fe Index obtained from the extractable fraction. Likewise, the relationships among the extracted nutrients and the total present in the foliar tissues were also studied.

The nutritional state of individual Castanea sativa Miller trees were diagnosed and some of the nutritional problems limiting their production were considered.

The critical levels of P, K, Fe, Mn and Zn extractable during the vegetative cycle 1.2 mg.g^‐1 , 5.3 mg.g^‐1 , 28 μg.g^‐1, 117 ug.g^‐1 and 20 μg.g^‐1, respectively.

The concentrations of total P, K, Fe. Mn and Zn were: 1.9 mg.g^‐1, 7.9 mg.g^‐1,148 μg.g^‐1, 270 μg.g^‐1 and 28 μg.g^‐1. The value of Fe‐Mn‐Zn balance extractable were 18–70–12, while the value of balance of the totals was: 34–59–7.

From Fe extractable index had values of 3.09 and for the total it would be 0,91.

The changes in the concentration of total and extractable nutrients present in leaves were the same in both the forms.

Key words:

• Active and Total Fe
• Equilibrium
• Fe Index