In terms of vegetal nutrition, the correct development of plants is usually compromised for one or more of these reasons:
– Inadequate contribution of nutritional elements or failure in their frequency.
– That the nutritional elements are not bioavailable for plants.
– Internal imbalances of certain elements.
These alterations even affect root growth and vegetative development. Other symptoms could be the premature fall of flowers or fruits and the appearance of malformations in the productive organs. The consequences of these imbalances have a negative impact associated with the profitability and depreciation of the harvest due to its poor appearance, which in the case of exporters, even leads to the cargo rejection when it reaches its destination.
Attention must be paid to symptoms that are revealed with relative ease in the leaves, through alterations in size, turgor decrease, colour changes or the appearance of necrosis, either in young developing leaves or in fully formed adult leaves, but also it is the case of appearing in other organs, such as buds or shoots.
We briefly share the visual symptoms that a plant shows, to help you identify the deficiency.
- Nitrogen (N). Chlorosis is observed throughout the plant, especially in the fully developed basal leaves, which begin to yellow from the apex to the base, with yellow veins. Peduncles shorten and become thinner. There are no necrotic areas or deformations. Poor development and advance of senescence.
- Phosphorus (P). Neither chlorosis nor necrotic areas are observed. The upper surface of the leaves is dark green with shades of reddish to purple, with a purplish underside. The basal leaves turn yellow, turning green after abscission. The development of the plant slows down.
- Potassium (K). Chlorosis at the edge of the adult basal leaves, maintaining their own colour in the centre of the leaf and on the veins. Apical and marginal necrosis is observed in fully developed leaves. Development slows down. Stem weakness.
- Calcium (Ca). Apical and marginal deformations and necrosis in developing areas such as buds and new leaves. The leaves curve downward. In fruits may appear softening, apical necrosis and cracking.
- Magnesium (Mg). In fully developed leaves, a mottled internerval chlorosis can be seen, which leads to necrosis as the deficiency increases. Peduncles weaken.
- Sulfur (S). Chlorosis is detected, initially, in developing leaves, which can spread to the rest of the plant, including the nerves, which begin to become marked and acquire reddish tones. There are no symptoms of necrosis. Growth is reduced.
- Iron (Fe). It is detected in the youngest parts of the plant. The leaves show chlorosis in the internerval spaces from the base, while the veins remain green, with a fine definition of the border. There is neither necrosis nor loss of turgor. The buds, especially the terminal ones, also show chlorosis.
- Manganese (Mn). It is detected in the young parts of the plant. The leaves show localized chlorosis, with the border of the thick nerve, and necrotic spots may appear in areas close to the veins in exceptional cases.
- Zinc (Zn). Lack of development and chlorosis is shown on the young leaves. The leaf margins retract, with the appearance of necrotic areas throughout the leaf, including the veins. Appearance of drops on the leaf due to a secretion of water in the stomata (guttation).
- Copper (Cu). Foliar chlorosis is seen in developing leaves, although not in the veins. Necrosis and loss of turgor is noticeable.
- Boron (B). Appearance of necrosis in young areas at the base of shoots and meristems. Young leaves pale to death from the base. Deformation of the fruits.
- Molybdenum (Mo). Appearance of chlorosis throughout the plant. First, in fully developing leaves. Malformations can be seen at a general level of the leaves, such as deformations from the edge of the leaf towards the centre, which evolve into necrosis.
A nutritional deficiency in one element leads to a metabolic and physiological imbalance in the plant which, depending on the severity, can affect other elements. For this reason, on certain occasions it is normal for visual symptoms to be difficult to differentiate or see intermingled with each other.
Identify these symptoms early and take your crop to its maximum potential.