for many enzyme functions and as a catalyst for the synthesis of
chlorophyll. It is essential for the young growing parts of plants.
Deficiencies are pale leaf colour of young leaves followed by yellowing of
leaves and large veins. Iron is lost by leaching and is held in the lower
portions of the soil structure. Under conditions of high pH (alkaline) iron
is rendered unavailable to plants. When soils are alkaline, iron may be
abundant but unavailable. Applications of an acid nutrient formula containing iron chelates, held in soluble form should
correct the deficiency.
fielder liquid iron
fielder iron plus
fielder soluble iron
is involved in enzyme activity for photosynthesis,
respiration, and nitrogen metabolism. Deficiency in young leaves may
show a network of green veins on a light green background similar to an
iron deficiency. In the advanced stages the light green parts become
white and leaves are shed. Brownish, black or greyish spots may appear
next to the veins . In neutral or alkaline soils, plants often show
deficiency symptoms. In highly acid soils, manganese may be available to
the extent that it results in toxicity.
fielder manganese 15
is necessary for cell wall formation, membrane integrity, calcium uptake
and may aid in the translocation of sugars. Boron affects at least 16
functions in plants. These functions include flowering, pollen germination,
fruiting, cell division, water relationships and the movement of hormones.
Boron must be available throughout the life of the plant. It is not
translocated and is easily leached from soils. Deficiencies kill terminal
buds leaving a rosette effect on the plant. Leaves are thick, curled and
brittle. Fruits, tubers and roots are discoloured, cracked and flecked
with brown spots.
fielder boron 15
fielder boron wp
is a component of enzymes or a functional cofactor of
a large number of enzymes including auxins plant growth hormones). It is
essential to carbohydrate metabolism, protein synthesis and internodal
elongation (stem growth). Deficient plants have the mottled leaves with
irregular chlorotic areas. Zinc deficiency leads to iron deficiency causing
similar problems. Deficiency occurs on eroded soils and is least available
at a PH range of 5.5 - 7.0. Lowering the pH can render zinc more available
to the point of toxicity.
fielder zinc C
fielder zinc 70
is concentrated in roots of plants and plays
a part in nitrogen metabolism. It is a component of several enzyme systems
that use carbohydrates and proteins. Deficiencies cause die back of the
shoot tips, and terminal leaves develop brown spots. Copper is bound tightly
in organic matter and may be deficient in highly organic soils. It is not
readily lost from soil but may often be unavailable. Too much copper can
fielder copper C
fielder copper 25
is a structural component of the enzyme that reduces nitrates to ammonia.
Without it, the synthesis of proteins is blocked and plant growth ceases.
Root nodule (nitrogen fixing) bacteria also require it. Seeds may not form
completely and nitrogen deficiency may occur if plants are lacking
molybdenum. Deficiency signs are the pale green leaves with rolled or cupped
fielder molybdenum df
Chlorine is involved in osmosis (movement of water or solutes in cells), the ionic
balance necessary for plants to take up mineral elements and in
photosynthesis. deficiency symptoms include wilting , stubby roots,
chlorosis (yellowing) and bronzing. Odours in some plants may decrease.
Chloride, the ionic form of chlorine used by plants, is usually found in
soluble forms and is lost by leaching. Some plants may show signs of
toxicity if levels are too high.
is involved in osmotic and ionic balance in plants.
is required for nitrogen fixation in legumes
and in the root nodules of non legumes. The demand for cobalt id much
higher for nitrogen fixation than for ammonium nutrition. Deficient
levels could result in nitrogen deficiency symptoms.
is found as a component of cell walls. Plants
with supplies of soluble silicon produce stronger, tougher cell walls making
them a mechanical barrier to piercing and sucking insects. It also enhances
plant heat and drought tolerance. Foliar sprays of silicon have also shown
benefits in reducing populations of aphids on field crops. Studies have
found that silicon can be deposited by the plants at the site of infection
by fungus to combat the penetration of the cell walls by the attacking
fungus. Improved leaf erectness, stem strength and prevention of iron and
manganese toxicity have all been noted as effects from silicon. Silicon has
not been determined essential for all plants but may be beneficial for many.