Abstract

Itajahya rosea was found growing in association with Leucaena leucocephala plants at Savitribai Phule Pune University campus in India. The species identity was confirmed by phylogenetic analysis based on ITS and LSU regions of rDNA, wherein, our fugus was placed along with I. rosea in phylogenetic tree. It represents first record of I. rosea from India. Frequent visitation by Drosophila species on I. rosea fruiting body particularly on gleba was observed. The Drosophila got attracted to the detached gleba under the laboratory conditions and even sometimes, they prefer to sit over the gleba as compare to their food banana. It suggested that I. rosea gleba or pseudostipe produces some compounds for attraction and feeding behavior of Drosophila species. Therefore, we characterized the volatile attractants produced by gleba and pseudostipe of I. rosea by GC-MS analysis. Nineteen compounds were identified from gleba while nine compounds were recovered from the pseudostipe. Out of them, blends of three abundant odor producing volatile compounds were reported namely, Hexadecane, Pentadecane and Nonadecane, which are responsible for attraction of Drosophila toward the gleba. Three fatty acids namely 9,12-octadecadienoic acid (Z,Z), hexadecanoic acid and benzoic acid ethyl ester produced are served as an appetitive signal through olfactory response of Drosophila, so the flies were feed on the gleba. Two pheromones’ compounds, heneicosane and (+)-(5S,9S)-5,9-dimethylpentadecane, were also reported in pseudostipe and gleba, respectively, which play a role in Drosophila for breeding. Our study highlights an intriguing chemical ecology of fungus–Drosophila interaction.

摘要

在印度 Savitribai Phule Pune 大学校园里，人们发现Itajahya rosea与Leucaena leucocephala植物一起生长。通过基于 rDNA 的 ITS 和 LSU 区域的系统发育分析确认了物种身份，其中，我们的河豚与I. rosea一起放置在系统发育树中。它代表了来自印度的I. rosea 的第一个记录。观察到果蝇物种频繁访问I. rosea子实体，特别是在 gleba 上。在果蝇得到了实验室条件下吸引到分离gleba甚至有时，他们的喜好，比较他们的食物香蕉坐过gleba。它表明I. roseagleba 或pseudostipe 产生一些化合物，用于吸引和捕食果蝇物种。因此，我们通过 GC-MS 分析表征了由 gleba 和I. rosea假菌柄产生的挥发性引诱剂。从 gleba 中鉴定出 19 种化合物，而从假菌柄中回收了 9 种化合物。其中，报告了三种产生大量气味的挥发性化合物的混合物，即十六烷、十五烷和十九烷，它们负责将果蝇吸引到 gleba。产生的三种脂肪酸，即 9,12-十八碳二烯酸 (Z,Z)、十六烷酸和苯甲酸乙酯通过果蝇的嗅觉反应作为食欲信号，所以苍蝇是在 gleba 上吃的。两种信息素的化合物，heneicosane 和 (+)-(5 S ,9 S )-5,9-二甲基十五烷，也分别在假菌柄和 gleba 中报道，它们在果蝇繁殖中起作用。我们的研究突出了真菌-果蝇相互作用的有趣化学生态学。