Brief Summary of Minutes of Annual Meeting

The business meeting was conducted by Chair, Pam Kazmierczak. John Anderson, NE-140 Administrative Advisor, was not present, but sent a report on the process for rewriting the NE-140 proposal. Committee members working on this new proposal include Michael Gold, Bradley Hillman, Bill MacDonald, Fred Hebard, and Don Nuss. The request to rewrite was accepted by the Northeastern AES Directors at their meeting in March 2002. The project will be submitted for review by 1 January 2003.

Anagnostakis nominated Chuck Rhoades for the position of Chair-Elect, Kazmierczak seconded the motion, and the group voted unanimously to elect Rhoades.

The NE-140 web page maintained by Ruby Meiz (URL: www.agnr.umd.edu/userforms/nera/projects) continues to function well.

Next year‘s meeting will be in Columbia, Missouri (Chair, Michael Gold), 18 - 20 September 2003.

1. To improve chestnut trees for timber and nut production, and determine the cultural requirements of chestnut seedlings in nursery and natural settings.

a) Corriea discussed the history of chestnut growing in California, the limited number of cultivars available, and the few diseases and insect pest problems that they have.

b) Grunder reported on her evaluation of the eight cultivars which she grows, and her experiments with Ethyphon to synchronize nut drop.

c) Golino explained the function of the Foundation Plant Material Service, and their plan to work with the western chestnut growers to import more cultivars.

d) Cunningham reported that they have planted seedlings for grafting new material as it becomes available.

e) Anagnostakis reported on her on-going root study with four hybrids planted in forest sites and a nursery in CT. Soil and leaf samples from three sites are being analyzed for total mineral content. Ca and P levels were 2X higher in nursery leaves than in forest leaves.

f) Hunt outlined the project in MO to develop a chestnut management guide, and work on chestnut business and marketing. Their best cultivars so far are ‘Willamette‘, ‘Qing‘, and ‘Peach‘.

g) Gerrath discussed the American chestnut recovery plan in Ontario, and his work with allozyme electrophoresis to look at genetic variability. He presented Adam Dale‘s report that 317 nuts were produced from their crosses in 2002.

h) Carlson is working on silviculture to prepare for reforestation projects. Both American chestnuts, and seedlings from a group of BC2 trees were planted and are being monitored. He is also trying a GISH procedure to hybridize chromosomes with labeled probes to determine the amount of Chinese genetic material present in hybrids.

i) Rhoades continues to study soil factors and their influence on root disease. He used ectomycorrhizae and soil amendments to look for effects. He is also starting to analyze soil and site factors in the West Salem, WI site with naturalized American chestnut trees.

j) Fulbright is continuing his cultivar trial, and looking for optimum pollinator positions within orchards. He also conducted a restaurant trial with nuts from several cultivars. Mich. State Univ. has purchased a chestnut peeler to help the chestnut co-op with their marketing. He reported on the trees from C. dentata seed irradiated and planted in the 1950‘s, and seedlings of the original trees which have been planted in various locations. He feels that some of them do have increased resistance to chestnut blight disease.

k) Anagnostakis presented a report from Schlarbaum on large Ozark chinquapins in the Ouachita National Forest in south eastern OK. Seed from the trees have been planted in a GA nursery for propagation and distribution for studies.

2. To better understand the interactions and ecology of the host/pathogen/parasite system at the molecular, organismal and environmental levels in order to develop effective biological controls for chestnut blight.

a) Anagnostakis reported on her 2002 examination of the two sites in CT where transgenic hypovirulent strains of C. parasitica were released, working with Nuss. The canopy-covered site (single release) had few living stems. The clear-cut site, repeatedly treated by Nuss over 3 years, had many large, living chestnut stems, with more in the treated plot than in the control plot. C. parasitica was isolated from cankers on living stems in the fall of 2002. Two isolates from the first study, and 10 from the clear-cut study (3 from the treated plot, 6 from the control plot, and 1 from outside the plots) were all orange in culture. All contained dsRNA, but none were transgenic. All of these hypovirus-containing strains will now be examined by Nuss to confirm that the virus came from the original transgenic strains used.

b) MacDonald presented an update on the West Salem, WI site of naturalized American chestnuts. This year 721of the 1330 cankers were sampled. Hypoviruses CHV1-EURO 7 and CHV3 COLI1-1 were both still found. There are now 12 vegetative compatibility types present in the C. parasitica population.

c) Double reported on the effect of vegetative compatibility on canker control with hypovirus treatment. Tree longevity was greater after 5 years when vegetatively compatible inoculum was used, and spring treatment was marginally better than fall treatment for tree response.

d) Fulbright is still studying the 973 bp mitochondrial insert found in C. parasitica strains from MI, which reduces virulence and sporulation. The insert was found in the first isolate from the West Salem trees.

e) Hillman is working on viruses and transposons of C. parasitica while on sabbatical at Okayama University in Japan. All are cytoplasmic and transmissible by anastomosis of the fungus, most have no coat protein and their dsRNA is in host-derived lipid vesicles, they have no extracellular stage, have widely varying effects on the fungus, and are phylogenetically diverse. Only the largest dsRNA band is genomic. The most closely related other virus is Barley Yellow Mosaic Virus.

f) Churchill is cloning C. parasitica genes in the pathway for orange pigment biosynthesis. She hopes to use gene tagging by insertional mutagenesis and do targeted PCR amplification.

g) Nuss continues to study the genomic organization and expression strategy of Hypovirus CHV1-Ep 713. The p40 coding domain clearly has a significant effect on fungus morphology. He also reported that they trapped 3000 insects in 2001 from the second transgenic-release test site (clear-cut plots reported in 2.a. above). All were checked, and none were carrying transgenic hypovirulent strains. Also in 2001, none of the isolates of C. parasitica from the control plot or outside the plots contained dsRNA. (2002 isolate results in 2.a. above).

h) Van Alfen reported on his studies of the affects of hypovirus on C. parasitica. The genes that are Kex-2-processed code for Cryparin, Laccase, and MF1-1 pheromone. Kazmierczak is using GFP-Green fluorescent protein to study virus transport within the mycelium of the fungus. She found vessels for Cryparin secretion in pycnidial initials but not in young hyphae. Most of the viral particles, however, were located in the hyphal tips.

1. Anagnostakis, S. L. 2001. The effect of multiple importations of pests and pathogens on a native tree. Biological Invasions 3:245-254.

2. Campbell, F. T., and Schlarbaum, S. E. 2002. Fading Forests II. Trading Away our Natural Heritage. Healing Stones Foundation, paper and compact disc. 128 p.

3. Dawe, A. L., and Nuss, D. L. 2001. Hypoviruses and chestnut blight: exploiting viruses to understand and modulate fungal pathogenesis. Annual Review of Genetics 35:1-29.

4. Gold, M., and Hunt, K. 2002. Establishment of a chestnut industry to enhance the viability of small farms in Missouri. IN: P. L. Byers, ed., Proc. 2002 Missouri Small Fruit and Vegetable Conference, 18-20 February 2002, Springfield, MO, p 11-26.

5. Hunt, K, Gold, M, and Reid, W. 2002. Growing Chinese Chestnuts in Missouri. Bulletin, University of Missouri Center for Agroforestry, Agroforestry in Action #4-2002, 12 pp.

6. Parsley, T. B., Chen, B., Geletka, L. M., and Nuss, D. L. 2002. Differential modulation of cellular signaling pathways by mild and severe hypovirus strains. Eukaryotic Cell 1:401-413.

7. Sasaki, A., Onoue, M., Kanematsu, S., Suzaki, K., Miyanishi, M., Suzuki, N., Nuss, D. L., and Yoshida, K. 2002. Extending chestnut blight hypovirus host range within Diaporthales by biolistic delivery of viral cDNA. Molecular Plant-Microbe Interactions 15:780-789.

8. Suzuki, N., and Nuss, D. L. 2002. The contribution of protein p40 to hypovirus-mediated modulation of fungal host phenotype and viral RNA accumulation. Journal of Virology 76:7747-7759.

9. Taylor, D. R. 2002. The evolution of hypovirulence in the chestnut blight system: implications for management options. Pp286-296 IN: Adaptive Dynamics of Infectious Diseases: In Pursuit of Virulence Management. U. Dieckmann, J. A. J. Metz, M. W. Sabelis, and K. Sigmund, eds. Cambridge Studies in Adaptive Dynamics.