Plant Deficiencies
The
correct diagnosis of nutritional deficiencies is important
in maintaining optimum plant growth. The recognition of
these symptoms allows growers to fine tune their
nutritional regime as well as minimize stress conditions.
However, the symptoms expressed are often dependent on the
species of plant growth, stage of growth, or other
controlling factors. Therefore, growers should become
familiar with nutritional deficiencies on a crop-by-crop
basis.
Eliminating Plant Deficiencies
Record keeping and photographs are excellent tools for
assisting in the diagnosis of nutrient deficiencies.
Photographs allow growers to compare symptoms to previous
situations in a step-by-step approach to problem solving.
Accurate records help in establishing trends as well as
responses to corrective treatments. You will find
pictures and brief descriptions of some of the most common
deficiencies in the plant world. Should you not find the
picture that resembles one of these deficiencies, check
our plant disease page, as it could be a disease.
Nitrogen (N)

Restricted
growth of tops and roots especially lateral shoots.
Plants become spindly with general chlorosis of entire
plant to a light green and then a yellowing of older
leaves which proceeds toward younger leaves. Older leaves
defoliate early.
Phosphorous (P)

Restricted
and spindly growth similar to that of nitrogen
deficiency. Leaf color is usually a dull dark green to a
bluish green with purpling of petioles and the veins on
underside of younger leaves. Younger leaves may be
yellowish green with purple veins with "N" deficiency and
darker green with "P" deficiency. Otherwise, "N" and "P"
deficiencies are very much alike.
Potassium (K)

Older
leaves show interveinal chlorosis and marginal necrotic
spots, or scorching, which progresses inward and also
upward toward younger leaves as deficiency becomes more
severe.
Calcium (Ca)

From
slight chlorosis to brown to black scorching of new leaf
tips and die- back of growing points. The scorched and
die-back portion of tissue is very slow to dry so that it
does not crumble easily. Boron deficiency also causes
scorching of new leaf tips and die-back of growing
points, but calcium deficiency does not promote the growth
of lateral shoots and short internodes as does boron
deficiency.
Magnesium (Mg)

Interveinal
chlorotic mottling or marbling of the older leaves which
proceeds toward the younger leaves as the deficiency
becomes more severe. The chlorotic Interveinal yellow
patches usually occur toward the center of leaf with the
margins being the last to turn yellow. In some crops,
the interveinal yellow patches are followed by necrotic
spots or patches and marginal scorching of the leaves.
Boron (B)

Slight
chlorosis to brown to black scorching of new leaf tips and
die- back of the growing points similar to calcium
deficiency. Also, the brown and black die- back tissue is
very slow to dry so that it can be crumbled easily. Both
the pith and epidermis of stems may be affected as
exhibited by hollow stems to roughened and cracked stems.
Sulfur (S)

Resembles
nitrogen deficiency in that older leaves become yellowish
green and the stems thin, hard and woody. Some plants
show colorful orange and red tints rather than
yellowing. The stems, although hard and woody, increase
in length but not in diameter.
Iron (Fe)

Starts
with interveinal chlorotic mottling of immature leaves,
and in severe cases, the new leaves become completely
lacking in chlorophyll, but with little or no necrotic
spots. The chlorotic mottling on immature leaves may
start first near the bases of the leaflets so that in
effect the middle of the leaf appears to have a yellow
streak.
Manganese (Mn)

Starts
with interveinal chlorotic mottling of immature leaves,
and in many plants it is indistinguishable from that of
iron. On fruiting plants, the blossom buds often do not
fully develop and turn yellow or abort. As the deficiency
becomes more severe, the new growth becomes completely
yellow, but in contrast to iron, necrotic spots usually
appear in the interveinal tissue.
Zinc (Zn)

In
some plants, the interveinal chlorotic mottling first
appears on the older leaves, and in others it appears on
the immature leaves. It eventually affects the growing
points of all plants. The interveinal chlorotic mottling
may be the same as that for iron and manganese, except
for the development of exceptionally small leaves. When
zinc deficiency onset is sudden, such as zinc left out of
the nutrient solution, the chlorosis can appear identical
to that of iron and manganese without the little leaf.
Copper (Cu)

Leaves
at top of the plant wilt easily followed by chlorotic and
necrotic areas in the leaves. Leaves on the top half of
the plant may show unusual puckering with veinal
chlorosis. Absence of a knot on the leaf where petiole
joins the main stem of plant, beginning about 10 or more
leaves below growing point.
Molybdenum (Mo)

These
deficiency symptoms in legumes are mainly exhibited as
nitrogen-deficiency symptoms because of the primary role
of molybdenum in nitrogen fixation. Unlike the other
micronutrients, molybdenum-deficiency symptoms are not
confined mainly to the youngest leaves because molybdenum
is mobile in plants. The characteristic molybdenum
deficiency symptom in some vegetable crops is irregular
leaf blade formation, known as whiptail, but interveinal
mottling and marginal chlorosis of older leaves also have
been observed.
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