Walnut Scion & Rootstock Improvement
Walnut Scion & Rootstock Improvement
Walnut Scion & Rootstock Improvement
University of California
Walnut Scion & Rootstock Improvement

Eastern States Collaboration

Collaborative Research in Tennessee on Thousand Cankers Disease

Scott Schlarbaum, University of Tennessee, and Mark Coggeshall, University of Missouri Center,  provided the following summaries of their ongoing activities. The photos highlight collaborative efforts that have been carried out in Tennessee.

Figs. 1 & 2. Black walnut and butternuts planted in the field, ready for grafting.

Fig. 1. Black walnut and butternuts planted in the field in Tennessee, ready for grafting.
Fig. 1. Black walnut and butternuts planted in the field in Tennessee, ready for grafting.
Fig. 2.
Fig. 2.

We have a large germination effort for black walnut and white walnut (butternut) open-pollinated genetic families. We have constructed soil beds in a greenhouse and planted the genetic families. The black walnuts were from collections in different TN counties and from trees that had Thousand Cankers Disease (TCD) to varying degrees. The butternuts are from central Tennessee and southwestern Virginia. We have transplanted them for eventual TCD screening to detect resistance. Pedigree will be maintained throughout all procedures.

Figs. 3, 4 & 5. Greenhouse soil beds.

Fig. 3.
Fig. 3.
Fig. 4.
Fig. 4.
Fig. 5.
Fig. 5.

We lift 1-0 seedlings from various mother trees, diseased and non-diseased. The seedlings are containerized and field planted for eventual screening.

Fig. 6. The seedlings in these raised beds will be grafted and eventually screened. Mark procures seedlings from Forrest Keeling Nursery, which has some of the best containerized seedlings in the world with strong, fibrous root systems. Grafts on these rootstocks will grow quickly.

Figs. 7 & 8. These photos show some of the grafts. We work together on all aspects of this project.

Fig. 6.
Fig. 6.
Fig. 7.
Fig. 7.
Fig. 8.
Fig. 8.

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