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DISTRUBUTION OF NEOTYPHODIUM IN LOLIUM PERENNE CULTIVARS AND ECOTYPES IN CENTRAL EUROPE
DISTRUBUTION OF NEOTYPHODIUM IN LOLIUM PERENNE CULTIVARS AND ECOTYPES IN CENTRAL EUROPE A HOLZMAN, J REINHOLZ, H OSTBOMKE, VH PAUL Universitaet-Gesamthochschule Paderborn, Department of Agriculture, Luebecker Ring , D-59494 Background and objectives Grasses of the family Pooideae can be infested by symbiontic fungi of the genus Neotyphdium. The fungi are strictly seed transmitted and can enhance their hostís resistance against biotic and abiotic stresses, but may also produce alkaloids toxic to livestock. Livestock toxicoses have been first reported from New Zealand and the USA, where infestation levels in fodder grasses (Festuca and Lolium species) are often more than 90%. As for central Europe is the origin of these fodder grasses, this symbiosis is presumed to originate from there. Despite this, problems with livestock are rarely reported in Europe and infestation levels in varieties and ecotypes are widely unknown. The objective of this paper was to investigate on the distribution of Neotyphodium in European Lolium perenne ecotypes and varieties, respectively. The influence of long term storage and are discussed. Materials and methods Seed lots of 84 Lolium perenne cultivars from the German list of registered cultivars (Beschreibende Sortenliste) and 53 Rumanian ecotypes were examined for endophyte presence. Grass seeds were stained with analine blue and examined microscopically for fungal hyphae. To investigate the influence of long term storage on the viability of the endophyte, ecotype seed was germinated and the seedlings examined for endophyte presence. 24 plants per seed lot sown before and 100 young plants per seed lot sown after three year storage were tested. To find out whether the endophyte is transmitted to all caryopses of a positive plant, we investigated also seeds obtained from the three year old plants (100 seeds from selected plants each). Results and conclusions From 84 cultivars of the German list of registered culitvars 10 were Neotyphodium - infested, the infestation rate range from 2 to 15%. In the 53 Rumanian ecotypes 24 were infested, here the infestation rate was more than 81% in 17 ecotypes. This dofference between infestation levels in European cultivars and European ecotypes has been reported before [1]. A possible explanation could be storage under unfavourable conditions for the endophyte during the breeding process. It is reported, that endophytes in seeds losw their viability soner than the embryo under the same conditions [2]. Under storage conditions of 40% relative humidity and 8-18deg. C we found very little loss of viability of endophyte. After a three year storage of 24 endohyte containing ecotypes, the average loss of endophyte vaibility in seeds was 6.3%. Investigation of the seeds in infested plants from the ecotype collection showed that some plants did not yield 100% positive seeds. Whether this fact is due to external or genetic reasons is still unknown. References [1] Dapprich P, Klose A, Paul VH 1994. International Conference on Harmful and Beneficial Microorganisms in Grassland Pastures and Turf. IOBC wprs Bulletin 17(1), 131-137 [2] Siegel MR, Latch GCM, Johnson MC 1987. Ann. Rev. Phytopath, 25, 293-315.