The symbiotic Epichloë festucae var. lolii endophyte produces alkaloids which can provide its host grass, perennial ryegrass (Lolium perenne L), with a selective advantage in both natural and agricultural managed ecosystems. This study focuses on understanding the alkaloid concentrations that occur in endophyte-infected perennial ryegrass during the early establishment phase. In a glasshouse experiment fungal alkaloid concentrations (peramine, lolitrem B, ergovaline, and epoxy-janthitrems) were measured in perennial ryegrass seedlings infected with E. festucae var. lolii proprietary strains AR1, AR37, NEA2, and NZ common toxic for 69 days after sowing. The endophyte becomes metabolically active, starting alkaloid production, as early as 6 days after sowing. Alkaloid concentrations peaked in 8- to 10- day-old seedlings due to a seedling growth slowdown. This study provides data showing that the loss of insect protection in endophyte-infected seedlings is linked to a reduction in chemical defence after seed-stored, maternally synthesised alkaloids are diluted by seedling dry matter accumulation.

中文翻译：

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内生细菌感染的多年生黑麦草幼苗建立过程中发生真菌生物碱。

共生的Epichloëfestucae var。萝莉内生菌产生的生物碱可以为其寄主草，多年生黑麦草（黑麦草）提供选择性的优势，无论是在自然环境还是农业管理的生态系统中。这项研究的重点是了解在早期建立阶段内生植物感染的多年生黑麦草中发生的生物碱浓度。在温室实验中，测定了感染了羊茅（E. festucae var ）的多年生黑麦草幼苗中的真菌生物碱浓度（过胺，lolitrem B，麦角花碱和环氧菊酯）。萝莉播种后的69天内，AR1，AR37，NEA2和NZ专有菌株常见有毒。内生菌最早在播种后6天就开始具有代谢活性，开始产生生物碱。由于幼苗生长减慢，生物碱浓度在8至10天大的幼苗中达到峰值。这项研究提供的数据表明，在种子储存的母本合成生物碱被幼苗干物质积累稀释后，内生植物感染的幼苗中昆虫防护能力的丧失与化学防御的降低有关。