Resource Book on Horticulture Nursery Management

11. Copper (Cu): Yong leaves permanently wilted without spotting or marked chlorosis.
Yellowing and chlorosis of normally green leaves. White tip or yellow tip diseases is
observed in grains with dwarfed or distorted heads.
12. Molybdenum (Mb): Lower leaves of tomato showing mottling, necrosis and curling
of leaf edges. In oats, leaves bend backward, later break at affected areas with
necrosis.
13. Chlorine (Cl): Leaves display the symptom of wilting of leaf blade tips. Chlorosis,
bronzing and necrosis are also observed in areas proximal to wilting.
14. Nickel (Ni): Visual deficiency symptoms of nickel have not yet been found
adequately. Its deficiency causes accumulation of nitrates and decrease in amino acid
content in barley containing less than 0.1mg Ni/Kg.
Role and Functions of Essential Nutrients
1. Nitrogen
i. Nitrogen is an essential constituent of proteins and chlorophyll and is present in
many other compounds in plant metabolism, such as nucleotides phosphatides,
alkaloids, enzymes, hormones, vitamins etc. It is thus a very basic constituent of
plant life.
ii. Imparts dark green colour to plants. It promotes vegetative growth in leaves, stem
and produces rapid early growth.
iii. It improves the succulence of leafy vegetables and fodder crops and increases the
protein content in it.
iv. Governs considerably the utilization of phosphorous, potassium and other
elements
2. Phosphorous
i. Phosphorous is a constituent of nucleic acid, phytin and phospholipids. An
adequate supply of Phosphorous early in plant life is important for the
development of the reproductive parts of the plant
ii. Phosphorous is also an essential constituent of majority of enzymes which are of
great importance in the transformation of energy, in carbohydrate metabolism, fat
metabolism and also in respiration (catabolism of carbohydrates) in plants. It is
closely related to cell division and development.
iii. Stimulates early root development and growth, their by helping to establish
seedling quickly.
iv. Brings about early maturity of crops particularly cereals and counter acts the
effects of excessive nitrogen.
v. Stimulates flowering, aids in seed formation, increases grain to stalk ratio. It also
improves the quality of food grains and other crops.
vi. When applied to legumes it enhances the activity of Rhizobium and increases the
formation of root nodules. Thus it helps in fixing more atmospheric nitrogen in
root nodules. With Phosphorous deficiency, legumes plants may simultaneously
suffer from nitrogen as well as potassium deficiency.
<strong>Resource</strong> <strong>Book</strong> on Horticulture Nursery Management : 50