Role of nutrients and their deficiency Symptoms
"Essential nutrients & their forms for plant uptake explained with diagram. Includes role of plant growth regulators in plant development."
🌿 Available Forms of Essential Nutrients and Their Role in Plant Growth Regulators
Plant growth regulators play a crucial role in the uptake and utilization of essential nutrients by plants. These naturally occurring or synthetic substances influence physiological processes such as cell division, elongation, flowering, and fruiting. Understanding the available forms of nutrients is essential in optimizing the application of plant growth regulators.

As shown in the image above, the uptake of these nutrient forms is heavily influenced by specific plant growth regulators like auxins, gibberellins, cytokinins, abscisic acid, and ethylene. These regulators not only affect root development and nutrient absorption but also regulate the mobilization and assimilation of these elements within plant tissues.
Nitrogen
- Imparts green color to plants, encourages vegetative growth
- Essential constituent of protein
- Constituent of protoplasm, chlorophyll, and coenzyme
- Plays an important role in the synthesis of auxin
- Lower leaves become yellow and dry
- V-shaped chlorosis on older leaves or yellowing at the tip
- Starvation disease due to nitrogen deficiency
- Buttoning in cauliflower
Phosphorus
- Increases disease resistance
- Enhances new cell formation and necessary for root development
- Required for grain formation and maturity of grains
- Essential constituent for nucleic acid and phytin
- Most essential functions are energy storage and transfer (acts as "energy currency")
- Life cycle of plant can't be completed, hence Phosphorus is called "key of life"
- Imparts dark green color in leaves, later develops red-purple coloration
- Sickle leaf disease
Potassium
- Stomata regulation
- Provides disease resistance in plants
- Cofactor for enzymes
- Formation and translocation of sugars
- Helps in chlorophyll formation
- Spot of dead tissue at tips
- Scorching and burning on margins of autumn leaves
- Rottle/dieback disease
Calcium
- Constituent of cell wall
- Mobile in plants, deficiency symptoms appear on meristem tip portion
- Terminal bud dies
- Tip hooking
- Blossom end rot of tomato (BER)
- Popping in groundnut
Magnesium
- Essential constituent of chlorophyll
- Chlorosis between veins
- Sand-drown disease of tobacco
Sulphur
- Sulphur oxidizing bacteria is Thiobacillus
- Essential for oil seeds and pulses, improves oil and protein content
- Akiochi disease of rice due to excess of hydrogen sulphide
- Tea yellow disease of tea
Iron
- Component of nitrate reductase
- Required for nitrogen fixation
- Acts as O2 carrier during respiration
- Interveinal complete chlorosis
- Scorching of leaf margin
- Yellowing of iron chlorosis in groundnut
Manganese
- Formation of chlorophyll
- Co-factor of enzyme
- Dead spot on leaves
- Marsh spot of pea
- Pahala blight of sugarcane
Copper
- Compound of plastocyanin
- Essential for photosynthesis/respiration
- Dieback and reclamation disease of cereals
Boron
- Necessary for pollen germination
- Only non-metal element among the micronutrient
- Necessary for translocation of sugars
- Involved in reproduction and germination of pollen
- Browning of cauliflower
- Top sickness of tobacco
- Fruit cracking of tomato
- Hard fruit of citrus
- Hen and chick disease of grape
Zinc
- Required for biosynthesis of hormones
- White bud of maize
- Khaira disease of rice
- Little leaf of cotton
- Mottled leaf of citrus
- Rosette formation
Cobalt
- Component of Vitamin B
- Essential for formation of a type of hemoglobin in N-fixing nodule tissue known as leghaemoglobin
- Acts as O2 carrier in roots
- Also known as animal protein factor
Molybdenum
- Absorbed as molybdate (MoO4-2) forms
- Important component of enzyme: Nitrate reductase
- Required for N-fixation in pulses
- Required for carrot and raphanus for sweetness
- Whiptail of cauliflower