Identifying nutrient deficiency in Plants / Tomato plants
Each of the mineral elements required by plants has its own set of
deficiency signs and symptoms. Many of the signs are similar in
appearance, but others are very distinct. The list below describes some
of the symptoms which each of the nutrient deficiencies may cause (these
may vary slightly between different plant species and depending on how
severe the deficiency is):
Plants are short; leaves tend to be pale green-yellow in color,
especially on the older foliage. On tomato plants, the undersides of
the leaves and stems can develop a purple colouration.
Plants are usually stunted and a dark green color. Symptoms
occur on the older leaves first and plant maturity is often delayed.
Phosphorus deficiency in some plant can be due to conditions being to
cold for the uptake of this nutrient.
The older leaves become yellowed with scattered dark brown or
black spots. Severe deficiency will stunt the plant and all foliage will
become yellowed and curled. On lettuce, the leaves may take on a
yellowed, bronzed appearance starting on the older foliage.
There may be a yellowing of the leaves, first seen on new growth.
Deficiency is common on tomato crops with the older leaves developing yellowed areas between the veins.
Young leaves are affected before older leaves and become
distorted, small in size with spotted or dead areas. Bud development is
inhibited and root tips may die. Blossom end rot on tomatoes is also
caused by a deficiency of calcium within the fruit tissue and is more of
a 'calcium transport' problem within the plant.
Deficiency shows as a distinct yellowing between the leaf veins
which stay green, on the new growth and younger leaves (this
distinguishes it from magnesium deficiency which shows first on the
older leaves). On crops
such as tomatoes, iron deficiency may show when conditions are to cold
for uptake, rather than be caused be an actual deficiency in solution.
Deficiency shows as wilted leaves which then become yellowed
and eventually turning a bronze color. Roots become stunted and
thickened near the tips.
Initially, an interveinal yellowing on the younger or older
leaves, depending on the plant types. Brown, dry areas may develop and
leaves may fall off.
Plant size is usually reduced; the growing point may die back.
Root tips often become swollen and discoloured. Leaves eventually become
thickened, brittle and may be curled with yellow spotting.
Short plants with a reduction in internodes length and leaf
size. Leaf edges may be distorted or puckered and yellowing between the
leaf veins may also develop.
Deficiency is rare, but young leaves may become dark green and twisted or misshapen, often with brown, dry spots.
Older leaves develop interveinal yellowing, progressing to the
younger leaves. Leaf edges may develop scorching or cupping of the
Nickel deficiency symptoms are not well established, although Nickel poor seeds show poor germination and vigour. Low nickel in leaves may result in leaf burn due to an inability by the plant to process the nickel.
Sodium can interfere with the utilisation of potassium, calcium
and magnesium. Insuring an adequate supply of potassium will help
offset the toxic effects of this element. When sodium accumulates in
leaves, it causes the tip of the leaves to die and a yellowing or
whitening of a plant's leaves and stems occurs due to a lack of
chlorophyll particularly on new growth.