potato
DESCRIPTION
qadriranaTRANSCRIPT
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
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.
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
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%)
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.