Persistence and production of tall fescue (Schedonorus phoenix) infected with a novel non-toxic Neotyphodium endophyte

VUJASSIN, J., GUNDEL, P.E., GOLLUSCIO, R. & C. CASAS

Rosario

Congreso; IX INTERNATIONAL RANGELAND CONGRESS - IRC2011; 2011

Tall fescue is an Eurasian species that is cultivated in temperate regions worldwide due to its high quality and winter production. This specie is usually infected with the fungal endophyte Neotyphodium coenophialum establishing a mutualism. Plants obtain ecological benefits such as enhanced competition ability and higher tolerance to different biotic and abiotic stresses. However, the fungal alkaloid ergot that mediates the tolerance to herbivores is also responsible of the known livestock disease “fescue toxicosis”. As part of forage breeding programs, there has been a selection of endophytes that, while it does not produce ergot alkaloid, are able to maintain the benefits for plants. These novel “non-toxic” endophytes have been introduced into tall fescue commercial varieties. The aim of this study is to evaluate the effect of a novel endophyte on the forage production of two commercial varieties under field experiment conditions.     Tall fescue is an Eurasian species that is cultivated in temperate regions worldwide due to its high quality and winter production. This specie is usually infected with the fungal endophyte Neotyphodium coenophialum establishing a mutualism. Plants obtain ecological benefits such as enhanced competition ability and higher tolerance to different biotic and abiotic stresses. However, the fungal alkaloid ergot that mediates the tolerance to herbivores is also responsible of the known livestock disease “fescue toxicosis”. As part of forage breeding programs, there has been a selection of endophytes that, while it does not produce ergot alkaloid, are able to maintain the benefits for plants. These novel “non-toxic” endophytes have been introduced into tall fescue commercial varieties. The aim of this study is to evaluate the effect of a novel endophyte on the forage production of two commercial varieties under field experiment conditions. Despite the expectations, the infection with novel endophyte did not produce any improvement in forage production. Alternatively, the negative effect of the fungus observed 166 days after sowing is consistent with previous works. These results suggest that the cost that novel endophytes may have for host plants at establishment depends on the variety. The benefits that the endophyte may deliver for host plant are generally expressed under stress conditions (e.g. drought). The 2009 was an atypical year with precipitations higher than the historical average and moderate temperatures. Therefore, the performance of forage varieties as affected by novel endophytes can be especially important in dry years, where the positive effects on persistence and production would be manifested.