POTATO

POTATO Solanum tuberosum

The cultivated potato is a tuber-bearing tetraploid specie Has 4 sets of chromosomes, i.e., 2n = 4X = 48

X = 12

There are approximately 150 species in the genus Solanum, which are tuber-bearing tetraploids, triploids, diploids

Family

Solanaceae (nightshade)

The centre of origin:

Peru, Chile, Bolivia, Ecuador

POTATO

4th leading world crop after wheat, rice, corn

The potato is an annual dicot when grown from botanical seeds.

But, treated as a perennial because it is commercially propagated

from tubers.

The tuber is the:

primary storage organ and major human food source

main commercial propagule for potato

IMPORTANCE

• An important staple food crop.

• Can be cooked alone or with meat, fish, chicken and vegetables.

• Used to make Chips.

• Tuber has about 70-75% water, 25-30% dry matter.

• It is a rich source of starch (about 20%).

• It also contains protein and minerals.

• It also has noticeable amount of vitamins, particularly vitamin C.

Production Statistics for the Year

2011-2012

• Cultivated through out the world.

• In Pakistan

– Area 185.1 thousand ha

– Yield 4104.4 thousand tonnes

– Average yield is 22.17 tonnes/ha

– Autumn crop----65%

– Spring crop------20%

– Summer crop----15%

Major Potato Producing Areas in Pakistan

• Punjab (92%)

– Okara (28%), Sahiwal (16%), Sialkot (10%), Kasur

(9%), Pakpatan (7%).

• Sindh (<1%)

– Khairpur (33%), Shikarpur (27%).

• KPK (6%)

– Nowshehra (18%), Swat (18%), Mardan (9%), Dir

(11%), Mansehra (9%) contribute 65%.

• Balochistan (2%)

– Kila Saifullah (48%), Kallat (19%), Pishin (13%).

• Northern Areas

– Hunza & Gilgit

Plant Structure

• The potato tuber is a

modified underground

stem.

• Plant has relatively

weak and shallow root

system.

Growth Stages Growth stage I: Planting to emergence

Growth stage II: Vegetative growth

Growth stage III: Tuber initiation

Growth stage IV: Tuber bulking

Growth stage V: Tuber maturation

Climate • Potato is a cool season crop, moderately tolerant to frost.

• It has a wide range of seasonal adaptability.

• Temperature is the most important factor influencing yield of potato.

• Young plant growth is the best at 24 ºC.

• Later on growth is favored by temperature of about 18 ºC.

• Tuber production is:

– maximum at 20 ºC

– Ceases at 30 ºC

• Short days are beneficial for tuber production.

Soil Deep, fertile, sandy to clay loam soils are preferable for potato.

Soil should have good water retention.

Impermeable layers in soil:

restrict root development

decrease rooting depth

restrict water availability to plant in dry periods

So, soil compaction greatly reduce potato yield.

Soil should have good aeration for root and tubers development.

Deep ploughing is done to have a good tilth.

FERTILIZERS Potato requires high amount nutrients.

FYM @ 30 tonnes/ha should be added 3 to 4 weeks before

planting.

Trail conducted in Punjab:

N @ 100 kg/ha

P2O5 @ 80-100 kg/ha

K2O @ 50 kg/ha

If fertilizers are applied at higher rate then yield will

increase

NPK @ 125:33:75 kg/ha (cost:benefit ratio1:5.10)

NPK @ 220:75:111 kg/ha (cost:benefit 1:11.59)

Band fertilizer

Planting Time

In plains

Planting time Harvesting time

Sept-Oct. Nov.-Feb

Mid to end of January March-April

In hilly areas

April-May

Seed Rate

• Autumn 2500-3000 kg/ha

• Spring 1500-2000 kg/ha

• Summer 1500-2000 kg/ha

SPACING

• In plains

• Ridge sowing: 30cm

• R X R : 45-60 cm

• In hilly area, tubers are planted in furrows,

spaced 30 X 60 cm.

• Planting depth should be: – 10 cm for spring & summer crop

– 15 cm for autumn crop.

IRRIGATION

• Keep the soil moist for the entire growing

season but at the time of tuber formation

should not be very high.

• No stress during tuber development.

• After 7 days

• Total 9 irrigations for autumn and spring crop.

• 12 irrigations if environment is dry.

• Hill crop in Kalam requires 2-6 irrigations.

Hollow heart due

excessive rapid growth

Knobbiness due to

watering after drought

Cultural Practices

• Soil compaction is usual after faulty

irrigation and fast weed growth before crop

emergence.

• First hoeing should be done quite early.

• For weed control use stomp, gramaxone

and/or round up.

• Earthing up after 30 to 40 days increases

tuber yield.

Harvesting and Yield Yield

20-25 t/ha

The size of the tuber continue to increase until the

vines become dry.

Potatoes can be harvested manually using spade or

by using mechanical harvester

Tubers should not be injured during harvesting.

After harvesting, tubers should be placed in shade

for curing.

Varieties

Red Skinned

Cardinal

Desiree

Symphonia

• White Skinned

– Diamont

– Sante

DISEASES • Wilt

– Chlorosis, drying and wilting of leaves

• Brown rot

– Wilting, yellowing and necrosis

• Early Blight

• Late Blight

• Wet and storage rot of tuber

• Dry rot

Symptoms of Diseases

• Black Scurf

• Common Scab

Symptoms of Diseases

• Wart

• Powdery Scab

Symptoms of Diseases

• Watery Wound

(Pythium)

Late Blight

Early Blight

Verticillium Wilt

Verticillium Wilt

Fusarium Dry Rot

Potato Viruses

• Potato Leaf Roll Virus (65-70%)

– Spring 40-60%

– Autumn 7-14%

• PVY (65-70%)

• PVX (10-30%)

• PVS (10-30%)

• PVA (10-30%)

Symptoms of viruses

Symptoms of viruses

Integrated Control Measures for Viruses

Integrated Control Measures for Viruses

INSECTS • Aphids

–Suck sap and spread viral diseases.

• Potato tuber moth

–Caterpillar mines in leaves and shoots and cause

leaf blotches and death of shoots.

–Moths lay eggs in tubers and on hatching larvae

penetrate in skin of tubers and make galleries.

• Nematode

–Infested plant look sickly and stunted, lower leaves

become yellow and get dropped.

–Tuber may also get infected.

• Stink bugs

–Nymphs and adults suck sap.