Steve Motsinger Orchard, Spring 2010

Pictures compare a susceptible and a resistant reaction to the SG form of the chestnut blight fungus implanted in trees in the Motsinger Orchard the fall of 2009. Also pictured are a BC3 (third backcross hybrid chestnut) tree and a pure American chestnut growing in the orchard.

  • The 1st photo shows a susceptible reaction to the SG form of the fungus on a BC3 tree often show that the fungus has spread beneath the bark from the point of inoculation up and down the trunk of the tree. Spores from the actively growing fungus appear on the reddened area of the trunk.
  • Chinese chestnut trees are expected to be very resistant to chestnut blight and are used as control trees in the orchard. Their reactions to inoculated blight are used to compare reactions to the same form of blight inoculated in hybrid chestnut trees in the orchard. Pure American chestnut trees which are expected to be very susceptible to inoculated blight are grown in the orchard and serve as control trees for comparison of reactions to inoculated blight. Bark around the inoculated area has been cut back to show how the Chinese chestnut tree has contained the spread of the fungus.
  • The third photo below is an backcross hybrid tree with American chestnut mother tree was from Lickstone Ridge in Haywood County, NC. The father tree was Graves Tree #210 at Meadowview Research Farms. The tree shown has the Clapper source of resistance.
  • The fourth photo shows a pure American chestnut tree. The seed was from a different tree at Lickstone Ridge identified by Mark Rogers of Canton, NC. So far the tree pictured shows no sign of blight infection. It was not inoculated in hopes that it will flower and produce pollen so it can be used in the Carolinas Chapter breeding program.