Secondary and Micronutrients For VEGETABLES AND FIELD CROPS
Plant nutrients in fertilizers are classified as major nutrients and micronutrients.
The most important.Major nutrients are nitrogen (N), phosphorus (P) and potassium (K).
Plants require these nutrients in relatively large amounts,
and these are the nutrients most likely to be deficient for plant growth.
The other major nutrients, also called secondary nutrients, are calcium (Ca),
magnesium (Mg) and sulfur (S).
They are also required in relatively large amounts but are less likely to be deficient.
Micronutrients are essential for plant growth, but plants require relatively small amounts of them.
They include boron (B), copper (Cu), iron (Fe),manganese (Mn), molybdenum (Mo) and zinc (Zn).
These elements may also be referred to as minor or trace elements, but “micronutrients” is preferred.
Calcium Deficiency Symptoms
Calcium deficiency is usually observed as a failure of terminal buds and apical root tips to develop.
In corn,new leaves fail to emerge from the whorl because of a sticky,
gelatinous material on the edges of the leaves.
The tips of these leaves are also very chlorotic (yellowish).
The young leaves of new plants are the first to be affected.
They areoften distorted and small, the leaf margins are often irregular,
and the leaves may show spotted or necrotic areas.
Magnesium Deficiency Symptoms
In corn, magnesium deficiency symptoms first appear as interveinal chlorosis in the older leaves.
Symptoms often appear early in the season in cold,
wet soils and may disappear as the soil warms up and dries.
Severe deficiency may cause stunting.In oats and wheat,
the older leaves show a distinctive chainlike yellow streaking.
In potatoes, the loss of green color begins at the tips and margins of the older.
leaves and progresses between the veins toward the centers of the leaves.
The leaves become brown or reddish and very brittle during the advanced stages of the deficiency.
Sulfur Deficiency Symptoms
Sulfur-deficient plants are generally light green, similar to plants with nitrogen deficiency.
The most likely crops to show a sulfur deficiency are those grown on sandy, low organic matter soils.
Legumes,especially alfalfa and others with a high sulfur requirement,
will normally be the first crops to respond to sulfur fertilization.
Dry edible beans that were not adequately fertilized with nitrogen have been
shown to respond to sulfur fertilizer.
Corn, small grains and other grasses are less likely to show sulfur deficiency.
Zinc Deficiency Symptoms
Zinc deficiency in corn appears as a yellow striping of the leaves.
Areas of the leaf near the stalk may develop a general white to yellow discoloration.
In severe deficiency, the plants have shortened internodes
and the lower leaves show a reddish or yellowish streak about onethird of the way from the leaf margin.
Plants growing in dark sandy or organic soils usually show brown or purple nodal tissues
when the stalk is split.
This is particularly noticeable in the lower nodes.
Copper Deficiency Symptoms
Copper deficiency in many plants shows up as wilting or lack of turgor
and development of a bluish green tint
before leaf tips become chlorotic and die.
In grains, the leaves are yellowish and the leaf tips look frost damaged.
Carrot roots, wheat grain and onion bulbs show poor pigmentation.
Alfalfa, lettuce,oats, onion, spinach, Sudangrass, table beet
and wheat are the most responsive crops on organic soils.
Boron Deficiency Symptoms
Boron deficiency in crops causes a breakdown
of the growing tip tissue or a shortening of the terminal growth.
This may appear as rosetting. Internal tissues of beets, turnips
and rutabagas show breakdown and corky, dark discoloration.
Molybdenum Deficiency Symptoms
Molybdenum deficiency in clover shows up as a general yellow to greenish yellow foliage color,
stunting and lack of vigor. The symptoms are similar to those caused by nitrogen starvation.
Early stages of the deficiency in cauliflower and broccoli appear as a marginal scorching,
rolling or curling upward, and withering and crinkling of the leaves .
In later growth stages, the deficiency shows up as “whiptail,”
especially in the younger leaves. The leaf blade is often very narrow or non-existent.
Older leaves show crinkling and marked yellow mottling between the veins.
In onions, molybdenum deficiency shows up as dying leaf tips.
Below the dead tip, the leaf shows 1 or 2 inches of wilting and flabby formation.
As the deficiency progresses, the wilting and dying advance down the leaves.
In severe cases, the plant dies.
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The most important.Major nutrients are nitrogen (N), phosphorus (P) and potassium (K).
Plants require these nutrients in relatively large amounts,
and these are the nutrients most likely to be deficient for plant growth.
The other major nutrients, also called secondary nutrients, are calcium (Ca),
magnesium (Mg) and sulfur (S).
They are also required in relatively large amounts but are less likely to be deficient.
Micronutrients are essential for plant growth, but plants require relatively small amounts of them.
They include boron (B), copper (Cu), iron (Fe),manganese (Mn), molybdenum (Mo) and zinc (Zn).
These elements may also be referred to as minor or trace elements, but “micronutrients” is preferred.
Calcium Deficiency Symptoms
Calcium deficiency is usually observed as a failure of terminal buds and apical root tips to develop.
In corn,new leaves fail to emerge from the whorl because of a sticky,
gelatinous material on the edges of the leaves.
The tips of these leaves are also very chlorotic (yellowish).
The young leaves of new plants are the first to be affected.
They areoften distorted and small, the leaf margins are often irregular,
and the leaves may show spotted or necrotic areas.
Magnesium Deficiency Symptoms
In corn, magnesium deficiency symptoms first appear as interveinal chlorosis in the older leaves.
Symptoms often appear early in the season in cold,
wet soils and may disappear as the soil warms up and dries.
Severe deficiency may cause stunting.In oats and wheat,
the older leaves show a distinctive chainlike yellow streaking.
In potatoes, the loss of green color begins at the tips and margins of the older.
leaves and progresses between the veins toward the centers of the leaves.
The leaves become brown or reddish and very brittle during the advanced stages of the deficiency.
Sulfur Deficiency Symptoms
Sulfur-deficient plants are generally light green, similar to plants with nitrogen deficiency.
The most likely crops to show a sulfur deficiency are those grown on sandy, low organic matter soils.
Legumes,especially alfalfa and others with a high sulfur requirement,
will normally be the first crops to respond to sulfur fertilization.
Dry edible beans that were not adequately fertilized with nitrogen have been
shown to respond to sulfur fertilizer.
Corn, small grains and other grasses are less likely to show sulfur deficiency.
Zinc Deficiency Symptoms
Zinc deficiency in corn appears as a yellow striping of the leaves.
Areas of the leaf near the stalk may develop a general white to yellow discoloration.
In severe deficiency, the plants have shortened internodes
and the lower leaves show a reddish or yellowish streak about onethird of the way from the leaf margin.
Plants growing in dark sandy or organic soils usually show brown or purple nodal tissues
when the stalk is split.
This is particularly noticeable in the lower nodes.
Copper Deficiency Symptoms
Copper deficiency in many plants shows up as wilting or lack of turgor
and development of a bluish green tint
before leaf tips become chlorotic and die.
In grains, the leaves are yellowish and the leaf tips look frost damaged.
Carrot roots, wheat grain and onion bulbs show poor pigmentation.
Alfalfa, lettuce,oats, onion, spinach, Sudangrass, table beet
and wheat are the most responsive crops on organic soils.
Boron Deficiency Symptoms
Boron deficiency in crops causes a breakdown
of the growing tip tissue or a shortening of the terminal growth.
This may appear as rosetting. Internal tissues of beets, turnips
and rutabagas show breakdown and corky, dark discoloration.
Molybdenum Deficiency Symptoms
Molybdenum deficiency in clover shows up as a general yellow to greenish yellow foliage color,
stunting and lack of vigor. The symptoms are similar to those caused by nitrogen starvation.
Early stages of the deficiency in cauliflower and broccoli appear as a marginal scorching,
rolling or curling upward, and withering and crinkling of the leaves .
In later growth stages, the deficiency shows up as “whiptail,”
especially in the younger leaves. The leaf blade is often very narrow or non-existent.
Older leaves show crinkling and marked yellow mottling between the veins.
In onions, molybdenum deficiency shows up as dying leaf tips.
Below the dead tip, the leaf shows 1 or 2 inches of wilting and flabby formation.
As the deficiency progresses, the wilting and dying advance down the leaves.
In severe cases, the plant dies.
More: www.xinyiindustrial.com
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