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32 p., 8 figuras y 2 tablas. -- The final version of this paper is publised at: https://www.sciencedirect.com/science/article/pii/S1754504818302745, The distribution of different Epichloë species within eight natural populations of Lolium perenne was studied. In total, 40.2% of the asymptomatic plants were infected by Epichloë festucae var. lolii or by Epichloë typhina. Both species occurred in sympatry in seven grass populations, and some plants had dual infections by both taxa. No hybrid taxa such as Epichloë hybrida were detected. Epichloë festucae strains were classified into two morphotypes, M1 and M3, according to culture characters, both morphotypes occurred in sympatry in seven populations. Plants bearing stromata produced by Epichloë typhina were observed, but asymptomatic plants infected by this species also occurred in seven populations. The alkaloid profile of Lolium perenne plants was related to the morphotype of their infecting strains: most plants infected by M3-strains were characterized by lolitrem, and those with M1-strains contained either ergovaline or lolitrem. Plants infected by Epichloë typhina were characterized by high peramine content., This work was financed by research grants AGL2011-22783 and AGL2016-76035-C2-1R, funded by the Spanish Ministry of Economy and Competitivity and cofounded by FEDER. Dr. Soto-Barajas is a researcher from the Cátedras CONACyT program of the Mexican Council of Science and Technology. Thanks are due to Javier Gomez Fuertes for technical help.

The plant microbiome is likely to play a key role in the resilience of communities to the global climate change. This research analyses the culturable fungal mycobiota of Brachypodium rupestre across a sharp gradient of disturbance caused by an intense, anthropogenic fire regime. This factor has dramatic consequences for the community composition and diversity of high-altitude grasslands in the Pyrenees. Plants were sampled at six sites, and the fungal assemblages of shoots, rhizomes, and roots were characterized by culture-dependent techniques. Compared to other co-occurring grasses, B. rupestre hosted a poorer mycobiome which consisted of many rare species and a few core species that differed between aerial and belowground tissues. Recurrent burnings did not affect the diversity of the endophyte assemblages, but the percentages of infection of two core species -Omnidemptus graminis and Lachnum sp. -increased significantly. The patterns observed might be explained by (1) the capacity to survive in belowground tissues during winter and rapidly spread to the shoots when the grass starts its spring growth (O. graminis), and (2) the location in belowground tissues and its resistance to stress (Lachnum sp.). Future work should address whether the enhanced taxa have a role in the expansive success of B. rupestre in these anthropized environments.

16 páginas, 10 figuras, 5 tablas, The plant microbiome is likely to play a key role in the resilience of communities to the global climate change. This research analyses the culturable fungal mycobiota of Brachypodium rupestre across a sharp gradient of disturbance caused by an intense, anthropogenic fire regime. This factor has dramatic consequences for the community composition and diversity of high-altitude grasslands in the Pyrenees. Plants were sampled at six sites, and the fungal assemblages of shoots, rhizomes, and roots were characterized by culture-dependent techniques. Compared to other co-occurring grasses, B. rupestre hosted a poorer mycobiome which consisted of many rare species and a few core species that differed between aerial and belowground tissues. Recurrent burnings did not affect the diversity of the endophyte assemblages, but the percentages of infection of two core species -Omnidemptus graminis and Lachnum sp. -increased significantly. The patterns observed might be explained by (1) the capacity to survive in belowground tissues during winter and rapidly spread to the shoots when the grass starts its spring growth (O. graminis), and (2) the location in belowground tissues and its resistance to stress (Lachnum sp.). Future work should address whether the enhanced taxa have a role in the expansive success of B. rupestre in these anthropized environments., MD and LM got funding through two UPNA’s doctorate scholarships. The research was supported by three projects financed by Ecoembes-SEO/Birdlife (Libera 2017), “la Caixa” Foundation and CAN foundation (LCF/PR/PR13/51080004), and the Spanish Ministry of Science and Innovation and FEDER funds (AGL2016-76035-C2-1R).

Epichloe fungi were isolated from Brachypodium sylvaticum with or without symptoms of choke disease collected at five sites in Japan. The morphological characteristics of the fungi corresponded to the description of Epichloe sylvatica. A phylogenetic analysis revealed that isolates derived from surface-sterilized tillers and single ascospores from stroma on its hosts were included in the same clade with those identified as E. sylvatica. In Japan, to date, Epichloe fungi causing choke disease on B. sylvaticum were listed only as Epichloe typhina. We confirmed that both stroma-forming and symptomless endophytes inhabiting B. sylvaticum in Japan are E. sylvatica, not E. typhina.

Cagas B., Machac R. (2012): Effect of some factors on the incidence of choke (Epichloe typhina) in grass seed stands in the Czech Republic. Plant Protect. Sci., 48: 10–16. Choke of grasses caused by Epichloe typhina occurred in 2008 and 2009 in more than 25% of grass seed stands of timothy (Phleum pratense and P. nodosum); a lower incidence was reported in orchard grass (Dactylis glomerata). A decline in disease incidence in 2010 was caused partly by a reduction in the total area of grasses grown for seed production and partly by a decrease of older grass seed stands. The incidence of choke in timothy varieties Odenwalder and Pampas was very high; they differed statistically from the other 24 grown cultivars. No difference was found among 21 varieties of orchard grass. The highest incidence of choke was observed in varieties Comer and Dolina (timothy) and Amera (orchard grass). The incidence of choke in cultivated varieties of Phleum spp. and D. glomerata was affected by stand age (the incidence of the disease in timothy was recorded in 13% of stands in the first cropping year and in 50% of stands in the fifth cropping year). Choke disease occurred in all regions where the species were grown for seed.

Man-made habitats - hotspots of evolutionary game between grass, fungus and fly The origin and effects of an evolutionary game between species from three different kingdoms (plants, fungi and animals) are presented. We provide scientific evidence that the interaction discovered in man-made habitats leads to an early stage of coevolution. The grass Puccinellia distans was observed to rapidly spread in new man-made habitats, while at the same time, it was colonised by the fungus Epichloë typhina. The invasion of infected grasses is accompanied by alterations in life histories of both species: P. distans developed features promoting long-distance spreading, whereas E. typhina changed its life cycle by forming sexual structures for the second time, later in the vegetative season. This enables the fungus to make use of the late shoots of the grass for sexual reproduction, even though it cannot be completed because the vector of spermatia necessary for fertilisation, female Botanophila flies, is not present at that time. This indicates that such uncoordinated evolutionary processes had taken place before interactions between organisms became so specialised that it is difficult to presume they were the result of natural selection. Moreover, these processes could have been initiated in man-made habitats that, in particular circumstances, can become coevolutionary hotspots.

Epichloë typhina comprises interfertile strains associated with several grass species in tribes Poeae, Aveneae and Brachypodieae. Molecular phylogenetics indicate that E. typhina is paraphyletic to E. sylvatica and E. clarkii. Although interfertility barriers are evident between E. typhina and E. sylvatica, E. clarkii is interfertile with E. typhina. However, E. clarkii is associated specifically with Holcus lanatus (Aveneae). We addressed the possibility that E. typhina is a complex of genetically isolated populations distinguishable by host specificity. Populations of E. typhina were sampled from three Cantons on a transect from southwest to northeast Switzerland, and from 1-3 host species in each Canton. No fewer than 20 isolates were obtained from each host at each location. The intron-rich 5'-end of the beta-tubulin gene was sequenced from each isolate, and all of the sequences were aligned for phylogenetic and coalescence analyses. There was no indication of geographic isolation of the populations, but no haplotypes (sequence variants) were shared between isolates from different hosts. Therefore, E. typhina appears to be a complex of genetically isolated sympatric populations that are specific for different hosts. Keywords: Brachypodium species, Clavicipitaceae, Dactylis glomerata, Epichloë, epichloë endophytes, grasses, host specificity, molecular phylogenetics, Poa species, Poaceae, population genetics

A mycoparasitic hyphomycete on the grass-parasitic ascomycete Epichloe typhina from Germany was identified as Clonostachys epichloe Schroers with morphological and molecular methods. A delicately balanced mutualism is known for the host fungus E. typhina and flies of the genus Botanophila . Studies of type material of Sphacelia typhina subsp. aeruginosa Sacc. collected in France in the 19th century revealed the synonymy of this taxon with Clonostachys epichloe, hitherto reported only for America and Asia under this name. Since C. epichloe apparently is highly host-specific and more common in Europe than previously known, it might benefit from this mutualism and reduce the development of E. typhina as well as the associated Botanophila flies. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) Neue Funde von Clonostachys epichloe, einem mykoparasitischen Pilz auf dem Poaceen-parasitischen Askomyceten Epichloe typhina, fur Europa Ein mykoparasitischer Hyphomycet auf dem Poaceen-parasitischen Askomyceten Epichloe typhina aus Deutschland wurde morphologisch und molekular als Clonostachys epichloe Schroers identifziert. Der Wirtspilz E. typhina bildet bekanntermasen mit Fliegen der Gattung Botanophila eine ausbalanzierte gegenseitige Abhangigkeit aus. Anhand von Typus-Studien an dem im 19. Jahrhundert aus Frankreich beschriebenen Hyphomyceten Sphacelia typhina subsp. aeruginosa Sacc. wurde die Synonymie dieses Taxons mit der vor wenigen Jahren beschriebenen Art Clonostachys epichloe nachgewiesen, die unter diesem Namen bisher nur aus Amerika und Asien bekannt war. Da C. epichloe sehr wirtsspezifisch und weiter verbreitet ist als bisher angenommen, wird eine mogliche Reduktion der Entwicklung von E. typhina und den assoziierten Botanophila -Fliegen diskutiert.

A survey for choke, caused by Epichloë typhina, in orchardgrass seed-production fields in Oregon was conducted annually from 1998 to 2003. In all, 99 fields were inspected, 57 in more than 1 year, to produce a set of 217 observations on disease incidence. There was a significant increase in disease incidence in 38% of the revisited fields, and a significant reduction of incidence in 3%. Yearly increases in disease incidence were as high as 29% in individual fields, but the average yearly increase from 1999 to 2003 was 5 to 8%. In 1998, 60% of all surveyed fields were infested with choke and, by 2003, 90% were infested. Average disease incidence in fields in their first year of production was

Main conclusion According to the results presented in this paper the fungal endophyteEpichloë typhinasignificantly improves the growth, PSII photochemistry and C assimilation efficiency of its hostDactylis glomerata. In this paper, we present a comprehensive study of the impact of the endophytic fungi Epichloë typhina on its plant hosts’ photosynthesis apparatus. Chlorophyll a fluorescence, gas exchange, immuno-blotting and spectrophotometric measurements were employed to assess photosynthetic performance, changes in pigment content and mechanisms associated with light harvesting, carbon assimilation and energy distribution in Dactylis glomerata colonized with Epichloë typhina. According to the results presented in this study, colonization of D. glomerata results in improved photosynthesis efficiency. Additionally, we propose a new mechanism allowing plants to cope with the withdrawal of a significant fraction of its energy resources by the endophytic fungi. The abundance of LHCI, LHCII proteins as well as chlorophyll b was significantly higher in E+ plants. Malate export out of the chloroplast was shown to be increased in colonized plants. To our knowledge, we are the first to report this phenomenon. Epichloë colonization improved PSII photochemistry and C assimilation efficiency. Elevated energy demands of E+ D. glomerata plants are met by increasing the rate of carbon assimilation and PSII photochemistry. Electronic supplementary material The online version of this article (doi:10.1007/s00425-015-2337-x) contains supplementary material, which is available to authorized users.

A 1998 survey was conducted in the Willamette Valley of Oregon, the major U.S. production area for orchardgrass seed, to determine the extent and severity of choke disease in Dactylis glomerata. This disease is a severe constraint to orchardgrass seed production in other parts of the world, but was unknown in Oregon prior to 1997. Thirty-seven fields, representing 27 cultivars and the geographical extent of production in the Willamette Valley, were selected from a list of fields registered for certification. Choke was found in 26 (70%) of the fields, and disease incidence ranged from 10%. In a survey of 16 fields located within 3.5 km of the 1997 discovery, choke was found in 14 fields, of which three had incidences >20%. Increase in disease incidence between 1997 and 1998 ranged from 2.1- to 3.3-fold in the three fields where disease increase was measured. One year after its presence was confirmed in Oregon, choke disease of orchardgrass is well-established throughout the orchardgrass seed producing region at damaging levels and is apparently able to increase and spread under the prevailing climatic and cultural conditions.

Cladosporium phlei as well as Epichloe typhina are natural fungal pathogens of timothy grass (Phleum pratense). An increase of resistance of the grass against C. phlei in the presence of E. typhina was already shown in several experimental designs. However, E. typhina can grow endophytically for long periods without causing external symptoms which makes the detection of infected plants and, thus, an exact evaluation of the resistance effect in the field difficult. New or modified methods were developed and used for the effective detection of the endophyte in field samples and for the isolation of both fungi. The relevance of a protective effect of E. typhina in timothy grass against infection with C. phlei was clearly established in field samples as well as in growth chamber and in vitro experiments.

Epichloë typhina, a fungal endophyte of cool season grasses, is heterothallic and an obligate out-crosser. In areas of endemism, its spermatia are moved between stromata of the two opposite mating types through egg-laying activities of Botanophila flies. In western Oregon, where the fungus was inadvertently introduced into seed-production fields of Dactylis glomerata (= orchardgrass, cocksfoot), flies do not appear to be the sole vectors for E. typhina fertilization. Here we examined the role of the common agricultural slug pest Deroceras reticulatum and mycophagous slug species Prophysaon andersoni and Arion subfuscus in E. typhina spermatia transfer. Frass from P. andersoni, A. subfuscus and D. reticulatum fed stromata of one mating type was transferred to stromata of the opposite mating type, resulting in 100%, 93% and 25% stromata fertilization respectively. An experiment designed to mimic field conditions examined stromata fertilization on E. typhina-infected plants of opposite mating type in the presence of slugs. Treatments with P. andersoni and D. reticulatum had greater stromata fertilization compared to the no-slug control, but the slug treatments were not different. This appears to be the first report of mollusks vectoring viable spermatia leading to the cross fertilization of stromata of different mating types.

The interactions of endophytes with plants are believed to evolve over time from parasitic to mutualistic, and in the seed-transmitted fungal endophytes, these interactions are conventionally treated as mutualistic. The weeping alkaligrass Puccinellia distans has recently dispersed to new habitats in Europe, where it was colonised by the seed-transmitted fungus Epichloe typhina. The E. typhina-infected weeping alkaligrass has a fertility advantage over -uninfected plants, but this advantage is held only over shorter time scales. We assess the antiherbivore value of E. typhina in mature weeping alkaligrass against common voles Microtus arvalis, a herbivore naturally co-occurring with weeping alkaligrass. In two consecutive food-choice tests conducted in a lab, we examined feeding by naive voles on E. typhina-infected (E+) and -uninfected grass (E−) originating from Central Europe. In the first test, all voles consumed comparable amounts of E+ biomass and E− biomass. In the subsequent test, the voles reduced their feeding rates by 57 %, but E+ food was avoided twice as frequently as E− food (75 vs. 33 % reduction). This result suggests that toxins produced by E. typhina repel herbivores soon after the first contact. We show that in addition to its direct fitness consequences, endophyte-mediated resistance to herbivory increases the fertility advantage of E. typhina-infected weeping alkaligrass. This effect can increase the ability of weeping alkaligrass to invade habitats with intense herbivory.

The hyperparasite Dicyma pulvinata is reported for the first time on Epichloë typhina, which causes choke disease in orchardgrass seed production fields in the Willamette Valley, OR. In an orchardgrass field near Corvallis, OR, D. pulvinata was found on 7% of E. typhina stromata. Infected stromata had fewer perithecia and appeared shrunken, desiccated, and pale gray to grayish-white, in contrast to the orange colored noninfected stromata with mature perithecia. In greenhouse inoculations, D. pulvinata significantly (P < 0.05) reduced perithecial formation on E. typhina. However, under field conditions, a significant (P < 0.05) reduction in perithecial development occurred in one trial initiated in mid-May, but not in a second trial initiated in early June, although D. pulvinata sporulated on 92% of the inoculated stromata from each trial within 72 h after their incubation in moist chambers. Under field conditions, D. pulvinata may have potential as a biocontrol agent of E. typhina if applied when stromata start to emerge during mid late April to early May when rain and high humidity conditions are typical. However, development of D. pulvinata would likely be limited by low humidity conditions that often occur during mid- to late June in the Willamette Valley. There are currently no effective chemical or cultural controls for choke in orchardgrass. Accepted for publication 3 November 2009. Published 16 February 2010.

, and M. C. Johnson. 1987. Fungal endophytes of grasses. Annual Rev. Phytopathol. 25: 293-315. White, J. F., Jr. 1987. Widespread distribution of endophytes in the Poaceae. Pl. Dis. 71: 340-342. , and G. T. Cole. 1986. Endophyte-host associations in forage grasses. IV. The endophyte of Festuca versuta. Mycologia 78: 102-107. ,and G. Morgan-Jones. 1987. Endophyte-host associations in forage grasses. IX. Concerning Acremonium typhinum, the anamorph of Epichloe typhina. Mycotaxon 29: 489-500. Yoshihara, T., S. Togiya, H. Koshino, S. Sakamura, T Shimanuki, T. Sato, and A. Tajimi. 1985. Three fungitoxic cyclopentanoid sesquiterpenes from stromata of Epichloe typhina. Tetrahedron Lett. 26: 5551-5554. sociations in fora e grasses. IX. Concerning remonium typhinum, the anam rph of Epichloe phina. Mycotaxon 29: 489-500. shihara, T., S. Togiya, H. Koshino, S. Sakamura

Population studies involving the grass Agrostis hiemalis infected with the endophytic fungus Epichloe typhina were made. Grass individuals were assessed for infection state (presence or absence of fungus), number of culms and fungal stromata, and location within plot. Using clustering and ANOVA procedures available in SAS, geometric groups were identified and analyzed. The tendency of plants to bear stromata was found to be significant with respect to both the plot (P < 0.05) and the cluster (P < 0.0001) within which plants occurred. A cultural study was made of the endophytes from one of the plots. Here isolates from a cluster containing stroma-bearing grass individuals were found to grow more rapidly than those from grass clusters without stromata on a variety of sugars naturally available in vivo. Histological studies of the host demonstrate that the endophyte is seed transmitted in a comparable fashion to endophytes in other grasses. It is suggested that the clustering of stromata-bearing plants in Agrostis hiemalis is the result of the presence of aggressive strains of endophyte within proximally located plants.

National audience; Epichloe typhina est un champignon ascomycète phytopathogène possédant 3 types de spores: spermaties, ascospores et conidies issues d'ascospores. Toutes ces spores sont produites par la phase épiphyte du champignon qui s'exprime sous la forme de manchons mycéliens enserrant les inflorescences des graminées de type Pooideae. L'implication de chacune de ces spores dans les processus infectieux est mal connue. Leur germination sur milieu artificiel et milieu naturel a été étudiée. Les spermaties ont une germination bipolaire et leur rôle semble limité à celui de gamète mâle. Les ascospores forment des tubes germinatifs pour la production de mycélium ainsi que des conidiophores qui produisent une nouvelle génération de spores asexuées: les conidies. Ces spores, bien que morphologiquement identiques aux spermaties, forment un tube germinatif et un conidiophore qui produit une nouvelle génération de conidies. Nous décrivons pour la première fois une trame mycélienne formée par l'accolement des ascospores d'E. typhina, produisant une quantité importante de conidies en conditions humides

Epichloë typhina, causal agent of choke, is a fungus that systemically infects the crown and foliage of Dactylis glomerata(orchardgrass). The process of infection of orchardgrass by E. typhina has not been fully established, but ascospores are believed to be responsible for new plant infections. The objective of this study was to determine if ascospores could serve as spermatia and fertilize stromata of E. typhina. To our knowledge, this is the first report of ascosporic fertilization in the genus Epichloë. Accepted for publication 28 January 2008. Published 21 April 2008.

Epichloë species (Clavicipitaceae, Ascomycota) are the causal agents of choke disease of grasses. This disease is characterized by the presence of cylindrical fungal stromata which wrap the immature inflorescences and inhibit the normal development of reproductive tillers. Using phenotypic and molecular characters, as well as mating compatibility tests, the fungus causing choke disease in Brachypodium phoenicoides (Poaceae) was identified as Epichloë typhina. A three year field experiment conducted with infected and uninfected plants of a single clone of B. phoenicoides showed no significant differences in biomass production during their vegetative growth stage, but the content of Ca, Mg, and Mn was greater, and that of Na was lower in infected plants compared to uninfected plants. Infected plants produced up to twice as many reproductive tillers than healthy plants, but their reproductive tissue biomass was smaller than that of healthy plants, because tiller development was arrested by choke forming stromata. This work was financed by project AGL2005-02839, granted by the Spanish Ministry of Science and Education.

Epichloe typhina is an endophytic fungus, while Cladosporium phlei is a pathogenic fungus of the timothy plant (Phleum pretense L.). We found two activities in the culture filtrate of E. typhina: one stimulated the pathogenic fungus, C. phlei, to produce phleichrome and the other inhibited its growth. The active ingredients that stimulated the production of phleichrome and inhibited the growth of C. phlei were isolated and characterized. The isolated compounds were identified as cyclo-(L-Pro-L-Leu) and cyclo-(L-Pro-L-Phe), which were stimulatory compounds, and p-hydroxybenzaldehyde, which was the growth inhibitory compound, based on an analysis of their spectral data. Of the two stimulatory compounds, cyclo-(L-Pro-L-Phe) showed higher activity. However, when 500 microg of cyclo-(L-Pro-L-Phe) was spotted on the TLC plate for bio-autography, a growth inhibitory zone was identified in the central red region, which contained phleichrome. On the other hand, phleichrome showed antifungal activity against E. typhina in the light, so it is assumed that there might be antagonism between the endophytic fungus, E. typhina, and the pathogenic fungus, C. phlei.

Fungitoxic sesquiterpenoid chokols A, B, C, F, and K, chokolic acid B, and chokolal A were synthesized from chokol G by modifying the side chain.

Two novel sphingoid derivatives were isolated from stromata of Epichloe typhina on timothy grass, Phleum pratense . Their structures were determined as 3-hydroxy-9-oxo-4-tetradecyl-5-oxa-1-azabicyclo[4.3.0]nonane-2-methanol and 3-hydroxy-9-oxo-4-(4 E -tetradecenyl)-5-oxa-1-azabicyclo[4.3.0]nonane-2-methanol by spectroscopic methods.

The population biology of grass endophytes is uniquely different from that in other groups of fungi given their status (primarily) as mutualistic symbionts, their effects on organisms interacting with hosts, and their variable means of horizontal and/or vertical transmission. Because grass endophytes are biotrophic and form perennial associations with their hosts, population biology of the fungi is tightly connected with that of the host. While the infection of grasses by endophytic fungi has been known for some time, their ecological role was seldom considered in early investigations. The first study that explicitly considered the population biology of endophytes was that of Bradshaw (1959) on Agrostis infected by Epichloe typhina (Pers.) Tul. However, most research has been conducted in the past 10 years, only after the ecological consequences of endophyte infection became widely appreciated.

A new synthetic route to optically active α, β-, β', γ'-unsaturated alcohols was established. The chiral enones (6 and 8), prepared from dimethyl malate via chiral phosphonates (4 and 5), were diastereoselectively reduced with Zn(BH4)2 to afford the 1, 3-syn derivatives (9 and 11). As an application of this 1, 3-asymmetric induction, the fungitoxic C-18 hydroxy unsaturated fatty acid isolated from stromata of Epichloe typhina was synthesized.

Seven novel fungitoxic sesquiterpenoids, chokols A, B, C, D, E, F and G, were isolated from stromata of Epichloe typhina on Phleum pratense. Their structures were determined by spectroscopic methods. The absolute configuration of chokol E was elucidated by its CD spectrum with Eu(fod)3 and a chemical correlation with epicyclonerodiol oxide.

Four fungitoxic C-18 hydroxy unsaturated fatty acids ( 1 )–( 4 ) have been isolated from stromata of Epichloe typhina . Their structures including the absolute configuration have been elucidated from spectral data.

Three new phenolic acid derivatives, 1,3- O -di- trans - p -coumaroylglycerol, 1,2- O -di- trans - p -coumaroylglycerol and chokorin were isolated from stromata of Epichloe typhina on timothy plants Phleum pratense . Their structures were established by spectroscopic and chemical means.

(1987). Endophyte-Host Associations in Forage Grasses. VI. A New Species of Acremonium Isolated from Festuca Arizonica. Mycologia: Vol. 79, No. 1, pp. 148-152.

Ascospores of Epichloe typhina germinated and produced phialides and conidia within a 24 h period, but produced no mycelium. This type of microcycle conidiation was referred to as iterative germination. All attempts at producing mycelium from ascospores failed; ascospores developed conidia under all cultural conditions tried in the study. Conidia produced during the process were viable, and morphologically similar to those produced in culture by mycelium, and to those produced by the fungus on its host meadow grass, Sphenopholis obtusata. This is the first report of microcycle conidiation by ascospores. Since the ascospores required no thermal or precultural induction period, it was concluded that in contrast to this phenomenon by conidia of other fungi, iterative germination to form conidia by ascospores of E. typhina is obligatory.