MODULE 3 Flashcards
__ the ability of the soil to supply essential nutrients to plants in sufficient and balanced amount and proper form
SOIL FERTILITY
What are the two aspects of the ability of the soil to supply essential nutrients to plants?
- Elements should be in proper amount
- Elements should be in their proper forns
Plant growth is limited by that nutrient present below the minimum requirement.
LIEBIG’S LAW OF MINIMUM
Plants, just like humans require certain elements for normal growth. When any of these are left out the plant will develop definite symptoms related to its shortage.
Plant Nutrients
Plant Nutrients are classified into ?
Primary Nutrients, Secondary Nutrients, Trace Elements
What are the primary nutrients?
- (N) Nitrogen
• (P) phosphorus - (K) Potassium
What are the Secondary Nutrients?
• Calcium
- Magnesium
- Sulfur
What are the Trace elements ?
- Chlorine
• Boron - Iron
- Molybdenum
- Manganese
• Zinc - Copper
____ are needed in relatively large amounts by plants.
Macronutrients
What are the elements under macronutrients?
*Oxygen
*Hydrogen
* Carbon
*Nitrogen
*Nitrogen
*Phosphorus
*Sulfur
*Potassium
*Calcium
*Magnesium
What are the elements under the Micronutrients?
*Iron
*Manganese
*Boron
*Molybdenum
*Copper
*Zinc
*Chlorine
__ are needed in relatively small amounts by plants. And they usually supplied by fertilizers.
MICRONUTRIENTS
Ionic form of NO3-, NH4+ ?
Nitrogen
Ionic form of H2PO-, HPO4=.?
Phosphorus
Ionic form of K+
Potassium
Ionic form of Ca++
CALCIUM
Ionic form of Mg++
Magnesium
Ionic form of SO4 2
Sulfur
Ionic form of Mn++
Manganese
Ionic form of Fe++
Iron
Ionic form of BO3=
Boron
Ionic form of Zn++
Zinc
Ionic form of Cu++
Copper
Ionic form of MoO4=
Molybdenum
Ionic form of Cl-
Chloride
What are the NUTRIENT ABSORPTION AND ASSIMILATION BY PLANTS ?
- Mechanisms of nutrient movement to roots
- Active and passive uptake
- Nutrient mobility
- Nutrient translocation and assimilation
• Nitrogen, Sulfur, Chloride, Boron
• Not held tightly by soil
• Plants can use nearly all of the nutrient if supply is limited
Mobile
• Phosphorus, Potassium, Calcium, Magnesium, Iron, Zinc, Manganese, Copper, and Molybdenur
• Tightly held by soil
• Nutrients absorbed from soil solution next to roots
Immobile
These processes are non-selective and do not require energy from metabolic reactions in the cell.
Passive uptake
___ occurs outside the casparian strip and plasmalemma as a barrier to diffusion and ion exchange.
Passive uptake
transport of ions into the inner cells require energy due to the higher concentration of ions beyond the plasmalemma and into the cytoplasm which is against an electrochemical gradient.
Active uptake
Entry of ions into the impermeable membranes of the other organs within the complex derives energy from metabolism.
Active uptake
The process is selective in that specific ions are transported by specific carriers.
Active uptake
Plant cells are negatively charged, thus anions must move against an electrochemical gradient.
True
___ usually appear on the plant when one or more nutrients are in short supply.
Nutrient deficiency symptoms
In many cases,____ may occur because an added nutrient is not in the forn the plant can use.
deficiency
Deficiency symptoms for specific elements are included on the “Key to Nutrient Disorders”.
True
Every soil is not susceptible to the same nutrient deficiencies.
true for Nutrient Deficiency Symptoms
_____low in organic matter are susceptible to ____ deficiencies whereas ___ is usually in adequate supply in clayey soils or soils high in organic matter.
- coarse-textured soils
- sulfur
- sulfur
• General chlorosis.
• Chlorosis progresses from light green to yellow.
• Entire plant becomes yellow under prolonged stress.
• Growth is immediately restricted and plants soon become spindly and drop older leaves.
Deficiency Symptoms - N
• Leaves appear dull, dark green, blue green, or red-purple, especially on the underside, and especially at the midrib and vein.
• Petioles may also exhibit purpling. Restriction in growth may be noticed.
Deficiency Symptoms - P
• Leaf margins tanned, scorched, or have necrotic spots (may be small black spots which later coalesce).
• Margins become brown and cup downward.
• Growth is restricted and die back may occur.
• Mild symptoms appear tirst on recently matured leaves.
Deficiency Symptoms - K
• Growing points usually damaged or dead (die back).
• Margins of leaves developing from the growing point are first to turn brown.
Deficiency Symptoms - Ca
• Marginal chlorosis or chlorotic blotches which later merge.
• Leaves show yellow chlorotic interveinal tissue on some species, reddish purple progressing to necrosis on others.
• Younger leaves affected with continued stress.
• Chlorotic areas may become necrotic, brittle, and curl upward.
Symptoms usually occur late in the growny season.
Deficiency Symptoms - Mg
• Leaves uniformly light green, followed by yellowing and poor spindly growth.
• Uniform chlorosis does not
OCCL
Deficiency Symptoms - S
• Leaves wilt, become chlorotic, then necrotic.
• Wilting and necrosis are not dominant symptoms.
Deficiency Symptoms - Cu
• Distinet yellow or white areas appear between veins, and veins eventually become chlorotic.
• Symptoms are rare on mature leaves.
Deficiency Symptoms - Fe
• Chlorosis is less marked near veins.
• Some mottling occurs in interveinal areas.
• Chlorotic areas eventually become brown, transparent, or necrotic.
• Symptoms may appear later on older leaves.
Deficiency Symptoms - Mn
• Leaves may be abnormally small and necrotic.
• Internodes are shortened.
Deficiency Symptoms - Zn
• Young, expanding leaves may be necrotic or distorted followed by death of growing points.
• Internodes may be short, especially at shoot terminals.
• Stems may be rough, cracked, or split along the vascular bundles.
Deficiency Symptoms - B
