In vitroandin vivopeppermint (Mentha piperita) growth promotion by nonmycorrhizal fungal colonization

Abstract

Summary• Here peppermint growth and terpene production of in vitro generated plants ( Mentha piperita ) in response to inoculation with a leaf fungal endophyte were characterized.• Peppermint plants were studied by means of morphometric, biochemical and image analysis, employing both in vitro and in pot cultures. Leaf essential oils were analysed by gascromatography-mass spectrometry.• The endophyte induced profound effects on the growth of peppermint, which responded with taller plants bearing more expanded leaves. The observed increase of leaf dry matter over leaf area suggested a real improvement of peppermint metabolic and photosynthetic apparatus. Root architecture was of the herring-bone type, showing greater dry biomass percentage over the total. A sustained lowering of (+)-menthofuran and an increase of (+)-menthol percentage concentrations were found in plants from both in vitro and pot cultures.• The study represents the first report on specialized endophytic fungi in peppermint green tissues and highlights some of the principal morphological and biochemical aspects of this mutualism. Effects exerted on plant growth and essential oil production in peppermint suggest further biotechnological applications.

Effect of a non-mycorrhizal endophyte isolated fromMentha piperitaon in vitro culture ofOcimum basilicumcuttings

“…Higher number of nodes and leaves resulted in a significantly larger (116%; p<0.01) total leaf area per plant (Fig. 2N), which was also observed in peppermint after inoculation with the same fungus (Mucciarelli et al, 2003).…”

“…PGP-HSF inoculation of sweet basil plants resulted in a greater root-to-shoot ratio (Fig. 2G) as a consequence of the increase of biomass, greater in roots than in shoots, as it occurs in peppermint plants (Mucciarelli et al, 2003). This parameter reflects the different investment of photosynthates between the shoot and root compartment of the plant and can be affected by different biological and non-biological factors.…”

“…In general, fungal endophytes play an important role in determining host resistance to fungal pathogens and pests, to optimize the absorption of nutrients and to increase the tolerance to abiotic stress such as temperature, pH, salt stress (Smith and Read, 2008). A peppermint endophyte, the ascomycetous plant growth promoter-hyaline sterile fungus (PGP-HSF), isolated from the host stem, has shown to enhance vegetative growth and to positively modify the essential oil composition in peppermint (Mucciarelli et al, 2003).…”

Óleo essencial de <i>Eucalyptus grandis</i> Hill ex Maiden no estímulo à micorrização de mudas de sibipiruna (<i>Caesalpinia peltophoroides </i>Benth.)

“…No entanto, dependendo da concentração de determinados compostos, poderá ocorrer relações de sinergismo, proporcionando a indução do crescimento de microorganismos ou plantas (BLUM, 1999;MAIRESSE, 2005). A partir desse efeito, alguns trabalhos têm mostrado a bioestimulação dos óleos essenciais no desenvolvimento microbiano (MARTINS et al, 2000;MUCCIARELLI et al, 2003;AKIYAMA et al, 2005) e em espécies vegetais (ALVES et al, 2004;BONALDO et al, 2007). Entretanto, não há relatos na literatura mostrando o efeito da aplicação do óleo essencial de Eucalyptus spp.…”

Fungos endofíticos em Annona spp.: isolamento, caracterização enzimática e promoção do crescimento em mudas de pinha (Annona squamosa L.)

“…(Rodrigues 1994), bananeira (Musa acuminata Colla) (Pereira et al 1999), coqueiro (Cocus nucifera L.) (Mariano et al 1997), citrus (Citrus limon L.) (Araújo et al 2001) e cajá (Spondias mombin L.) (Rodrigues & Samuels 1999). Em outras culturas como algodoeiro (Gossypium hirsutum L.) (Gasoni & Gurfinfel 1997), hortelã-pimenta (Mentha piperita L.) (Mucciarelli et al 2003), milho (Zea mays L.) e fumo (Nicotiana tabacum L.) (Franken et al 1998) resultados promissores têm sido obtidos com a utilização desses fungos na promoção do crescimento de plantas.…”