Thursday, August 9, 2012

Root Knot Nematodes to be banished from the island!!!

Southern Root Knot Nematodes are plant parasitic, microscopic roundworms in the soil, which feed on the root systems of plants, increasing disease potential and starving plants of water and nutrients.
As the summer temperatures rise so do the populations of Root Knot Nematodes making mid summer growing near impossible. 

 So we are taking advantage of the heat and using the sun to "solarize" the soils.

Keeping the soil covered with plastic for 6-8 weeks to trap the radiant heat is a safe and effective treatment for managing some biological and fungal soil diseases like verticillium wilt, as well as "cooking" soil pest organisms like the root knot nematodes.
Upon removal of the plastic we will inoculate the beds with our compost to replenish the population of beneficial bacteria and fungi.  Then we will plant a late season crop of tomatoes, cucumbers, squash, and beans.
How do you recognize these microscopic pests?
The galls are easily seen on the root system of a plant as rotting and swollen "bumps" (remember that legume plants have similar looking nitrogen fixing nodules that are a normal part of their root system.) 
Inspect trouble plants when you pull them up for these bumps on their roots.  If you find evidence of nematode damage do not compost that plant material and be careful not to "spread" the problem by sanitizing tools between plot/bed maintenance.
         
Plant Resistant Varieties:

There are newly available organic, non-gmo, seeds becoming available for summer crops with resistance to RKN.  This summer we planted Carolina Wonder Bell Peppers, Tropic VFN Tomatoes (both from Southern Exposure Seed Exchange), and a sweet potato slip called Nemagold. 
So far all looks (and tastes) good!