at least 16 functions: flowering, pollen germination,
fruiting, cell division, water relationships,
movement of hormones, cell wall formation, membrane
integrity, calcium uptake, movement of sugars.
Immobile; easily leached. Def.: terminal bud
die back causes rosette of thick, curled, brittle
leaves or brown, discolored, cracked fruits,
tubers and roots.
in osmosis (movement of water or solutes
in cells), ionic balance necessary to take
up mineral elements and photosynthesis. Def.:
wilting, stubby roots, yellowing, bronzing.
Scents in some plants may be decreased. Leached
by nitrogen fixing bacteria; formation of
B12 vitamin; formation of DNA. Will extend
life of cut flowers such as roses. Def.:
may result in nitrogen deficiency.
for nitrogen metabolism; component of enzymes
- may be part of enzyme systems that use
carbohydrates and proteins. Bound tightly
in organic matter. May be deficient in highly
organic soils. Not readily lost from soil
but may be unavailable. Def.: die back of
shoot tips; terminal leaves develop brown
spots. Excess is toxic.
functions; catalyst for synthesis of chlorophyll;
essential for new growth. Def.: pale leaves,
yellowing of leaves and veins. Leached by
water and held in lower parts of soil. High
pH soils may have iron present but unavailable
activity for photosynthesis, respiration
and nitrogen metabolism. Def.: young leaves
are pale with green veins similar to iron
deficiency; advanced stages-leaves are white
and drop; brown, black or gray spots may
appear next to veins. Plants in neutral or
alkaline soils often show def. Acid soils
may increase uptake causing toxicity.
part of enzymes that reduce nitrates to ammonia
for amino acid development essential to protein
formation; required by nitrogen fixing bacteria.
Def.: pale leaves with rolled, cupped margins.
Seeds may not form. Nitrogen deficiency may occur
if plants are lacking Mo.
recognized as essential. Required for the
urease enzyme to break down urea into usable
nitrogen and for iron uptake. Seeds require
nickel to germinate.
nitrogen metabolism in many plants, involved
in osmotic (water movement) and ionic balance
in plants. Def.: yellowing of leaves and
leaf tip burn; may inhibit flower formation.
of cell walls; enhances resistance to sucking
insects and fungi.Foliar sprays reduce populations
of aphids on some plants. Enhances leaf presentation;
improves heat, drought and cold tolerance;
improves photosynthesis; extends bloom life.
Def.: wilting, poor fruit and flower set,
increased susceptibility to insects and disease.
Disease resistance is enhanced by regular
part of enzymes including auxin (growth hormone)
synthesis, carbohydrate metabolism, protein
synthesis, stem growth. Def.: mottled leaves,
irregular yellow areas. Zinc deficiency leads
to iron deficiency. Occurs in eroded soils;
least available at pH of 5.5-7.0. Lower pH
can cause availability to the point of toxicity.