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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.

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.

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.

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.

, 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

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.

Summary Spore discharge from Epichloe typhina can be observed with the unaided eye. A method is described for studying the rate of spore liberation. Discharge tends to be periodic with a minimum in the morning and a maximum in the late afternoon or evening. In fairly dry air spore discharge continues for several days provided that the water supply to the host tissue is maintained, but when the transpiration stream is stopped by severing the stem, discharge soon ceases.