Limestone soils, pH and a non-adequate iron-based fertilization are the main causes for iron chlorosis
Chlorophyll is a natural pigment mainly present in leaves and which takes part in a fundamental process for human life: photosynthesis. Nitrogen, magnesium and iron are the essential nutrients that the plant needs in order to synthesize chlorophyll.
Iron is a necessary microelement which is however often ignored by farmers in fertilization. It is not very mobile within plant tissues and this is the reason why symptoms of iron deficiency are mostly visible in young leaves, through a yellow colour (chlorotic), showing the absence of chlorophyll synthesis (green) and a low photosynthetic activity. The agricultural land is rich in iron, but the assimilable form, or soluble one, is very low.
Iron chlorosis is a widespread problem, especially in tree crops characterized by a multi-year cycle and by some objective limitations, since they struggle to store a correct quantity of iron.
The low availability of assimilable iron in the soil is the primary cause for deficiency. This type of chlorosis is defined as lime-induced since the high concentrations of active limestone and the elevated pH block iron (precipitation of iron-based salts) and highly limit its availability to the plant. Italian tree crops (grapevine, citrus fruits, kiwi, stone fruits...) are generally planted in soils rich in limestone with an elevated pH (over 8,0).
In order to tackle this difficulty, there are different aspects to take into account:
- choice of a rootstock tolerant to high concentrations of limestone;
- use of iron-based fertilizers;
- irrigation management, since irrigation water brings carbonates and bicarbonates in the solution, making them active and inhibiting iron absorption.
Among these aspects, what could contribute the most to provide iron is an adequate iron-based fertilization planning.
Nano.T® Fe, thanks to its innovative patented formulation, allows to increase the effectiveness of iron absorption since the iron-phosphate within the product and the nano-dimension (<100nm) form compounds that protect the microelement against carbonates and other inorganic salts in the soil.
After using Nano.T® Fe in fertigation, the product stays in the soil and moves through the mass flow and in proximity of roots, avoiding precipitations. Also, it allows the plant to absorb iron with long-lasting effect. This ensures a nutrient effect and prevents from chlorosis, since the iron that is not absorbed by the plant remains available enriching the soil.