Potatoes/Solonaceae

Potatoes/Solonaceae

1. Varieties

   • First Earlies
     • Home guard
   • second earlies
     • Maris Piper
   • Maincrop
     • Rooster
     • Kerr pink
     • Golden wonder
     • High dry matter

2. Cultivation

   • Soil suitability
     • Deep, well-drained sandy loam
     • pH 5.5-6.0
     • Stone Free
   • Rotation
     • 1 in 4 years
     • last crop before lime
   • Prep of seedbed
     • Ploughed to 22cm
     • Remove stones from soil
     • 2 drills 172cm apart
   • Sowing seeds
     • 10cm below ridge
     • 20-35cm spacing
     • 40,000-60,000 per ha.
     • Potato planter
     • Feb-April
     • Chitting/Sprouting
       • Start growing early
       • increased yield
       • Earlier harvest
       • Longer growing season
       • essential for early variteies
   • Fertiliser application
     • 10-10-20
       • done by broadcasting
     • Nitrogen
       • increased yield
       • excess can cause watery tubers
       • susceptible to blight
     • Commercial place in 2 bands to promote uniform growth
     • Phosphurous
       • increase dry matter
       • promotes early rooting
     • Potassium
       • same as nitrogen

3. Weed control

   • Weed control
     • Earthing up
       • Prevents greening of tubers
       • supports the stem
       • pest control
     • Selective Herbicides
     • Weeding by hand
     • Scuffling
     • certified seeds
     • Shading

4. Harvest

   • Earlies late may
   • Maincrops late Sept-Oct
   • Haulms killed/burned off
     • Left in soil for 3 weeks for skin to toughen up
     • Makes harvesting easier
     • Prevents blight in tubers
   • Potato harvester is used

5. Storage

   • Well ventilated shed
   • Frost free
   • Dry and cool
   • No vermin
   • Dark
   • Growth inhibitors

6. Yield

   • 30-40 tonnes/ha main crop
   • 7-10 tonnes/ha Earlies

7. Causes of low dry matter

   • Too much nitrogen
   • Delays maturity
   • Lack of potassium
   • type/category of potatoes
   • Lack of sunshine
   • Add FYM to prevent

8. Pest

   • Wireworms
     • Larvae of click beetle
     • Can be present after grassland in rotation
     • Use insecticides
     • Eat tubers and reduce yield
   • Slugs
     • Common in wet summers
     • Slug pellets
   • Aphids
     • Vectors for viruses
     • Eat leaves
     • insecticides

9. Disease

   • Blight
     • Blight prevention
       • Certified seed
       • use resistant varieties
       • use suitable fungicide
       • Listen for weather alerts
       • earthing up
       • Remove volunteers
     • Fungus caused by Phytophthora infestans
       • Spores travel distances of 1.4km
       • Germinate in humitd weather at 10 degrees
       • Spores wash down and rot tubers after rain
     • Yellow spots that turn black
     • white fur on the underside
   • Black leg
     • Bacterial Pectobacterium carotovorum
     • Prevents the emergence of the seedling
     • Leaves turn yellow and stem turn black
     • survive in wet & cool conditions
     • Remove all volunteers and inspect the seed potato for damage
   • Virus
     • leaf roll
       • Stunted growth and leaves roll up
     • Virus Y
       • Necrotic spots on tubers
       • Mosaic leaves