Green Planet

INTRODUCTION

onion, (Allium cepa), herbaceous biennial plant in the amaryllis family (Amaryllidaceae), grown for its edible bulb.

Onions are low in nutrients but are valued for their flavour and are used widely in cooking.

The common onion has one or more leafless flower stalks that reach a height of 75–180 cm (2.5–6 feet), terminating in a spherical cluster of small greenish white flowers.

REQUIREMENTS

• Soil - Sandy soil.

• Temperature - 10 to 15 ° C for good growth and 20 to 30 ° C

• pH -6.2 to 6.8

IRRIGATION

One irrigation is necessary immediately after transplanting particularly in rainy season in Northern India where temperature at the time of transplanting is very high.

Wherever, there is erratic power supply in rainy season, transplanting is recommended 8 hours after irrigation particularly in Karnal area.

In kharif season depending upon the rains 8-10 irrigations are enough.

Late-kharif crop requires 12-15 irrigations while in rabi seasons 15-20 irrigations are given.

At bulb formation, irrigation is necessary and moisture stress at this stage results in low yield.

The field should not be kept dry for long which otherwise results in splitting and also force maturity.

Frequent and light irrigation at weekly intervals in general (2 acre inch per irrigation) results in good bulb development and increase in yield.

Sprinkler and drip irrigation methods increase onion yield significantly .

Irrigation should be stopped when tops mature and start falling in rabi season.

In kharif season it should be stopped 10 days before harvesting. Last irrigation 10-15 days before harvesting gives lower storage losses.

CULTIVATION

One irrigation is necessary immediately after transplanting particularly in rainy season in Northern India where temperature at the time of transplanting is very high.

Wherever, there is erratic power supply in rainy season, transplanting is recommended 8 hours after irrigation particularly in Karnal area.

In kharif season depending upon the rains 8-10 irrigations are enough.

Late-kharif crop requires 12-15 irrigations while in rabi seasons 15-20 irrigations are given.

At bulb formation, irrigation is necessary and moisture stress at this stage results in low yield.

The field should not be kept dry for long which otherwise results in splitting and also force maturity.

Frequent and light irrigation at weekly intervals in general (2 acre inch per irrigation) results in good bulb development and increase in yield.

Sprinkler and drip irrigation methods increase onion yield significantly .

Irrigation should be stopped when tops mature and start falling in rabi season.

In kharif season it should be stopped 10 days before harvesting. Last irrigation 10-15 days before harvesting gives lower storage losses.

NUTRIENT DEFICIENCY

1. DEFICIENCY OF NITROGEN

Leaves become yellowish green erect and upright curled, wilted and dwarf.

At maturity tissue above bulbs become soft.

TREATMENT :

Use

NITROKING

2-3 ml per litre

of water

Use

SPALL90

0.5 ml per litre

of water

2.DEFICIENCY OF PHOSPHORUS

Slow growth, maturity blazed.

Leaf colour becomes light green and bulbs have few dried outer peals.

Tip burn in older leaves.

TREATMENT :

Use

NITROKING

2-3 ml per litre

of water

Use

SPALL90

0.5 ml per litre

of water

3. DEFICIENCY OF POTASSIUM

Since potassium is very mobile within the plant, symptoms only develop on young leaves in the case of extreme deficiency.

Tip burn symptoms, leaves become dark green and erect.

Bolting promoted.

Older leaves become yellow and necrotic.

TREATMENT :

Use NITROKING

2-3 ml per litre

of water

Use SPALL90

0.5 ml per litre

of water

4. DEFICIENCY OF SULFUR

The leaves show a general overall chlorosis.

The yellowing is much more uniform over the entire plant including young leaves.

TREATMENT :

Use NITROKING

2-3 ml per litre

of water

Use SPALL90

0.5ml per litre

of water

5. DEFICIENCY OF MANGANESE

Leaves show tip burn, light coloured and curling.

Growth restricted.

Bulbing delayed with thick necks.

TREATMENT :

Use Manganese EDTA

0.5 gm per

litre of water

Use Grow

2 ml per litre

of water

Use SPALL90

0.5 ml per litre

of water

6. DEFICIENCY OF ZINC

Growth restricted.

The leaves show interveinal necrosis.

In the early stages of zinc deficiency the younger leaves become yellow and pitting develops in the interveinal upper surfaces of the mature leaves.

As the deficiency progress these symptoms develop into an intense interveinal necrosis but the main veins remain green.

TREATMENT :

Use Zinc EDTA

0.5-01 gm per litre

of water

Use NITROKING

2-3 ml per litre

of water

Use SPALL90

1ml per litre

of water

7. DEFICIENCY OF IRON

Complete yellowing of young leaves.

The most common symptom for iron deficiency starts out as an interveinal chlorosis of the youngest leaves, evolves into an overall chlorosis, and ends as a totally bleached leaf.

iron has a low mobility, iron deficiency symptoms appear fi rst on the youngest leaves.

Iron deficiency is strongly associated with calcareous soils, anaerobic conditions, and it is often induced by an excess of heavy metals.

TREATMENT :

Use Ferric EDTA

0.5-01 gm per litre

of water

Use NITROKING

2-3 ml per litre

of water

Use SPALL90

0.5 ml per litre

of water

DISEASES

1. FUNGAL DISEASE: CONTACT-BASED FUNGAL DISEASE

1. Stemphylium blight(Stemphylium vesicarium)

TREATMENT :

Use PPFC

2-3 gm per litre

of water

Use SpAll90

0.5 ml per litre

of water

1. FUNGAL DISEASE: CONTACT-BASED FUNGAL DISEASE

2. Purple Blotch – Caused by Alternaria porri

TREATMENT :

Use PPFC

2-3 gm per litre

of water

Use SpAll90

0.5 ml per litre

of water

1. FUNGAL DISEASE: CONTACT-BASED FUNGAL DISEASE

3. Anthracnose (twister disease) – Colletotrichum gleosporiodes

TREATMENT :

Use PPFC

2-3 gm per litre

of water

Use SpAll90

0.5 ml per litre

of water

1. FUNGAL DISEASE: CONTACT-BASED FUNGAL DISEASE

4. Downy mildew ( Peronospora destructor)

TREATMENT :

Use PPFC

2-3 gm per litre

of water

Use SpAll90

0.5 ml per litre

of water

2. FUNGAL DISEASE: SYSTEMIC-BASED FUNGAL DISEASE

1. Damping Off

TREATMENT :

Use Fungohit

2-3ml per litre

of water

Use SpAll90

0.5 ml per litre

of water

2. FUNGAL DISEASE: SYSTEMIC-BASED FUNGAL DISEASE

2. Botrytis fungus

TREATMENT :

Use Fungohit

2-3ml per litre

of water

Use SpAll90

0.5 ml per litre

of water

2. FUNGAL DISEASE: SYSTEMIC-BASED FUNGAL DISEASE

3. ONION SMUT(Urocystis cepulae)

TREATMENT :

Use Fungohit

2-3ml per litre

of water

Use SpAll90

0.5 ml per litre

of water

2. FUNGAL DISEASE: SYSTEMIC-BASED FUNGAL DISEASE

4. PINK ROOT(Phoma terrestris)

TREATMENT :

Use Fungohit

2-3ml per litre

of water

Use SpAll90

0.5 ml per litre

of water

2. FUNGAL DISEASE: SYSTEMIC-BASED FUNGAL DISEASE

5. WHITE ROT( Sclerotium cepivorum)

TREATMENT :

Use Fungohit

2-3ml per litre

of water

Use SpAll90

0.5 ml per litre

of water

2. FUNGAL DISEASE: SYSTEMIC-BASED FUNGAL DISEASE

6. FUSARIUM BASAL ROT(usarium oxysporum f.sp. Cepae)

TREATMENT :

Use Fungohit

2-3ml per litre

of water

Use SpAll90

0.5 ml per litre

of water

3. VIRUS

1. Onion Yellow Dwarf Virus Disease

TREATMENT :

Use Virohit 2-3 ml per litre of water
Use virosol 2-3 ml per litre of water
Use PPNP 1 ml per litre of water
Use SpAll90 0.5 ml per litre of water

3. VIRUS

2. Irish Yellow Spot Virus

TREATMENT :

Use Virohit 2-3 ml per litre of water
Use virosol 2-3 ml per litre of water
Use PPNP 1 ml per litre of water
Use SpAll90 0.5 ml per litre of water