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Symptoms of Deficiency In Essential Minerals -part 3

Potassium (K)

Potassium deficiencies show first in older leaves and are displayed as: yellowing; singed or scorching of leaf margins with small necrotic areas that start small and get bigger; brittle stems accompanied by withering leaf tips; interveinal chlorosis starting at the base of young leaves; reddening and upwards leaf curl in older leaves.

In vegetative stage, plants develop too slow and are stunted. In bloom phase, flowers develop slowly and fail to achieve normal size. Deficiencies of potassium are a major cause of small harvests.

Excess potassium interferes with calcium and magnesium uptake.

Potassium is essential in function and formation of enzymes and proteins. It is also essential in regulation of osmotic pressure and in most metabolic cellular processes.

Calcium (Ca)- (immobile in plant, immobile in soil)

Deficiencies show first in new, young growth. Calcium moves slowly within plants and concentrated in roots and older growth. That’s why young growth shows deficiency signs first.

Calcium deficiency symptoms include: leaf tips, leaf edges and new growth turn brown and die; chlorosis, necrosis, & distorted leaf margins; leaf tips hooking, turning brown and black, and dieing off.

Deficiency is not the only problem associated with calcium. If too much calcium is present early in a plant’s life cycle, growth is stunted. In other phases of growth, calcium excess interferes with magnesium and potassium uptake.

Calcium is transported via water to plant tissues, but if calcium levels in root zone media are too low, calcium deficiency can occur regardless of what levels are in the plant aboveground.

Because calcium is immobile, it cannot be easily translocated to the region of active growth in the shoot tip. Thus, calcium deficiency can cause severe reduction in new growth.

Although calcium may be adequate in the lowest leaves, levels in the meristematic upper plant region can still be low, causing defective upper leaf growth followed by necrotic patches in young leaves.

During early blooming phase, calcium deficiency can affect shoot growth, resulting in abortion of flower and bud structures.

Moderate calcium deficiency results in bended or twisted leaves, along with white streaks or white leaf margins in new leaf growth.

Calcium deficiencies make roots stubby and twisted and can cause root death.

Severe calcium deficiency can destroy all new growth and cause leaf mutations.

Calcium is crucial to cell elongation and is an important component in cell walls. It acts as a binding agent between cells and enhances uptake of negatively charged ions such as nitrate, sulfate, borate and molybdate.

Calcium is important for uptake of most macro and micro nutrients. Calcium is responsible for strong growth and very important in bud set and water uptake.

Calcium is a major constituent of cell walls, is critical to root and leaf development, seed production, pollen germination, cell mitosis, cell division and floral maturity.

Calcium binds primarily to cell walls and cell membranes. The high concentration of calcium in the cell wall and cell membranes provides rigidity to the plant cell wall structure. The absence of calcium causes degradation of the cell wall and lead to a softening of the plant tissue.

Adequate calcium helps plants resist fungal infections, which are often a big problem in hydroponics grow rooms.

Calcium plays a vital role in cell and root replication.

Magnesium - (Mg) (mobile in plant, immobile in soil)

Magnesium deficiencies show first in older, lower leaves. The symptoms start from the margin inwards. The leaf mid-rib and veins remain green while leaf margins are yellow or whitish, sometimes leaving a green arrowhead shape in the centre of the blade.

Interveinal chlorotic mottling or marbling of older leaves proceeds toward younger leaves as magnesium deficiency becomes more severe. This is sometimes accompanied by leaf tips curling upwards.

Chlorotic interveinal yellow patches can occur near leaf centers. In these cases, leaf margins are the last to turn yellow.

Interveinal yellow patches then progress to necrotic spots or patches and scorching of the leaf margins. In some cases, leaves die and drop off.

Magnesium shortages result in defective bud production and inadequate bud development.

Excess magnesium interferes with calcium and potassium uptake.

Plants use magnesium to: produce chlorophyll; regulate enzymes for transport of nutrients and carbohydrates in the plant; cell replication; seed production.

Magnesium is an important co-factor in production of ATP, the compound that helps plants transfer energy. It is also a bridge between ATP and enzyme activity.

Flowering and fruiting plants use more and more magnesium as they progress towards maturation and harvest.

Magnesium helps plants generate energy through photosynthesis and is also crucial to protein synthesis.

Sulfur - (S) (moderately mobile in plant, immobile in soil)

Deficiencies show up on older leaves first. Then they show up on younger leaves, turning them light green, then yellow. These symptoms are accompanied by slow growth. Leaves lose color, but veins remain green.

Sulfur deficiency symptoms are easily recognizable and are frequently confused with the nitrogen deficiency symptoms.

Sulfur deficiency causes small and spindly plants with short, slender stalks and reduced growth rate with delayed maturity.

An overdose of sulfur can cause premature dropping of leaves.

Some plants require as much sulfur as they do phosphorus. Sulfur is a component of cystine and methionine (amino acids that make up plant proteins). Sulfur is therefore a component of plant proteins.

It also has a major role in root growth and chlorophyll production. Sulfur is essential to seed production and overall plant hardiness. It is an enzyme activator and coenzyme compound. Sulfur enhances flavor and odor; it also is a formative part of chloroplasts and nucleic acid proteins. Sulfur deficiency decreases protein synthesis and causes significant reduction in leaf chlorophyll levels.

Please note that augmentation of sulfur is NOT achieved by the use of sulfur burners.

Boron - (B) (immobile in plant, mobile in soil)

Deficiencies show up first in younger leaves; they turn yellow. Boron deficiencies resemble calcium deficiencies. Symptoms include stunting, discoloration, death of growing tips, and floral abortion.

Boron deficiencies stunt roots, mutate leaves, and create brittle leaves that appear bronzed or scorched.

Boron deficiency symptoms first appear at growing points. This results in a stunted appearance and short internodes (rosetting). Both the pith and epidermis of stems may develop hollow, roughened or cracked stems.

Leaf margins discolor and die backs. Necrotic spots develop between leaf veins. Deficient leaves become thick and they may wilt with necrotic and chlorotic spotting.

If you have a potassium deficiency, plants have a hard time absorbing boron.

Excessive boron can cause the same kinds of problems as calcium deficiency cause. To complicate matters, the symptoms of excess boron can resemble the symptoms of deficient boron.

Boron is used for sugar transport within the plant. It helps with cell replication, production of amino acids, pollination, seed production, carbohydrate synthesis and transport, cell division, differentiation, maturation, respiration and growth, and water uptake.

Boron is essential for plant growth but its mode of action is poorly understood. Boron is taken in by roots and transported via xylem to other parts of the plant. In the cell membrane it is mainly present as a borate ester. Boron is involved in lignification of cell walls and in differentiation of xylem.

Boron plays a regulating role in synthesis of cell walls. as well as in stabilization of constituents of the cell wall and cell membranes. Boron deficiency immediately results in inhibition of primary and secondary root growth.

Boron regulates phenol metabolism and synthesis of lignins by forming a stable borate ester with phenolic acids.

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