Demo root lesion nematode

• You are potato grower and grow potatoes in a 1:3 rotation.
• You had a field sampled with the Combi method in August, immediately after a spring barley crop.
  Result Pratylenchus penetrans (root lesion nematode) 900 larvae/100 cc.
• You are growing potatoes in 2010 and 2013.
• You have sown fodder radish after the spring barley crop in 2009 but you might have made a better choice.
• For the next rotation you can choose from the following crops
  
  

  Crops	Green manure crops
  Potatoes	Perennialy ryegrass
  Sugar beet	Fodder radish
  Spring barley	Japanse oats
  Maize

• Which rotation gives the highest net income?