Brief Summary of Minutes of Annual Meeting

The annual NC227 meeting was held at the Albuquerque Marriot, Albuquerque, NM on February 17, 2003. The meeting was held in conjunction with the Sorghum Improvement Conference of North America. Jeff Pedersen, Chair of NC227 called the meeting to order and participants introduced themselves. Minutes from the 2002 annual meeting were distributed and approved. The agenda for the current meeting was distributed and Dr. Vanderholm opened discussion with an administrative update. He indicated that the Agricultural Appropriations Bill finally passed both the House and Senate and total appropriations were slightly increased over the previous year. Dale reminded us that NC227 would expire in one year in October 2004 and that we needed to decide whether our group continue as a NC project (or Southern, S), change to a coordinating committee or information exchange group (NCR or SRIEG), or do nothing and allow the project to terminate on September 30, 2004. Dale indicated that he would retire July 1, 2003 and would no longer serve as our administrative liaison, but would continue = time as Facilities Director at UNL. Following Dr. Vanderholms update, individual state reports were given (see attached). During these presentations, Gary Odvody informed the group that Debra Frederickson had left Zimbabwe due to political instability and moved back to the UK. Jeff Pedersen put forward a motion that we officially add Deanna Funnell to NC227 but indicated that Dr. Vogel with ARS in Lincoln, NE would have to give permission before she could serve.

Discussion for the remainder of the meeting centered on the question of project renewal. Dr. Vanderholm outlined our options and explained the difference between the various types of projects and committees. The majority of those present wanted to continue on in some fashion, probably not as a NC project but rather as a NCR committee. Gary Odvody, Mitch Tuinstra, Tom Isakeit, and Dianna Funnell volunteered to serve as a writing committee and to prepare a first rough draft of the new project proposal.

The meeting concluded following election of Tom Isakeit as the next secretary. The 2004 meeting will be held in Corpus Christi, TX at the TAES Center and hosted by Gary Odvody.

NEBRASKA: Ergot was discovered at the UNL Experiment Station, Ithaca, NE in September 2002. The disease was found on a very late maturing sorghum A-line in an isolation plot being used for production of hybrid seed by the UNL sorghum breeding program. Several field studies were established, but the severe drought destroyed all field experiments.
Currently we are working on sensitivity of detection and detection in mixed infections with grain weathering fungi. Our reliable detection minimum is 2 -5 spores. We can reliably detect Claviceps africana SSU DNA when total DNA from C. africana is mixed with total DNA from a number of fungi (Fusarium spp. and Alternaria spp.) at a ratio of 1:20, Claviceps DNA:other fungi DNA.

TEXAS: During the winter months, three to four ergot species including Clavceps africana were observed on heads of pearl meet (Pennisetum glaucum). Despite high inoculum from an adjacent male-sterile sorghum, incidence of C. africana in millet was low and typically one to three sphacelia per head when present. Macro- and secondary conidia of C. africana from sorghum and millet were similar in morphology, abundance, and production. Among the ergot species present on pearl millet, only C. africana had readily-observable secondary sporulation in the field. This is thought to be the first observation of pearl millet naturally infected by C. africana because previous host status as determined only by inoculation.
Three A-lines and six hybrids were planted in monthly intervals over five months at the Texas Agricultural Experiment Station near College Station. The hybrids represented a range of ergot reactions, based on previous studies. A-lines had a high severity of ergot (40-79%) during a flowering period of late May to early June, a low (0-5% severity during a mid-July flowering period and, again, a high severity during mid-August and mid-September. The A-lines showed no consistent order in relative susceptibility with the five planting dates. Ergot severity was less with the hybrids as compared with the A-lines. Only NC+8RI 8, which had a low amount of ergot in Weslaco, also was consistently low during the five flowering periods in College Station.
A survey of sorghum ergot was conducted in the Texas Panhandle in cooperation with seed companies. Data such as flowering dates, and GPS locations of individual fields was collected from 300 fields in the region. Weather data from the North Plain Potential Evapo-transpiration (NPPET) network was also collected and correlated to disease incidence. Doppler radar images for rainfall estimation are being used as the basis for a web-based site specific risk assessment model for sorghum ergot. A prototype, web-based risk assessment system has been developed.

KANSAS: Inoculation studies being conducted at Kansas State University have identified several different sources of ergot resistance. The sorghum accessions IS8525, IS14131, IS14257, and IS14357 were shown to express some levels of ergot resistance not related to efficient fertilization. Subsequent studies revealed that the ergot resistance trait in these lines was not stable across environments. The expression of resistance derived from these sources was strongly influenced by temperature and was not effective in cool environments. Given these considerations, IS8525 is currently the best source of resistance for use in sorghum crop improvement. Higher levels of resistance are desired.
Exotic sorghum accessions from the Kansas State University sorghum collection were screened for ergot susceptibility in a greenhouse in Manhattan, Kansas. Six entriesIS14485, PI199869, IS14215, IS14237, IS14297, and IS18799showed no visible signs of ergot infection after artificial inoculation. These lines and a susceptible check, TxArg1, were crossed to A3Tx430 in the greenhouse in 2001-2002 to produce male-sterile F1 hybrids in A3-cytoplasm.

Frederickson, D.E. and G.N. Odvody. 2003. Inhibition of germination of sphacelial conidia of Claviceps africana following treatment of seed-sphacelia admixtures with captan. Crop Protection, Vol. 22 (1) (2003) pp. 95-98. Montes, N., G. Odvody, H. Williams, and T. Isakeit. 2002. Development of a sorghum ergot (Claviceps africana) prediction model for hybrids in northern Mexico. Phytopathology 92:S57 (Abstract).
Reed JD, Tuinstra MR, McLaren NW, Kofoid KD, Ochanda NW, Claflin LE. 2002. Analysis of combining ability for ergot resistance in sorghum. Crop Science 42:1818-1823.
Reed JD, Tuinstra MR, Ramundo BA, Claflin LE. 2002. Analysis of Resistance to Ergot in Sorghum and Potential Alternate Hosts. Crop Science 42:1135-1138.
Stack, J. P., Partridge, J. E. Delserone, L. M. Tooley, P. W., and Jensen, S. G., 2002. A PCR-based diagnostic procedure for the identification of Claviceps africana. Plant Disease.
Workneh, F. and Rush, C. M. 2002. Evaluation of relationships between weather patterns and prevalence of sorghum ergot in the Texas Panhandle. Phytopathology 92:659-666.