Trichoderma harzianum strain T-22 (T22) has the ability of enhancing root growth and plant development. The aim of this research is to explain the biochemical basis of the direct plant-growth-promoting activity of T22. Seven days after the transfer to root-inducing medium, in vitro-cultured shoots of GiSeLa6® (Prunus cerasus × Prunus canescens), an important Prunus rootstock for sweet and sour cherry varieties, were inoculated with T22. Indole-3-acetic acid (IAA), trans-zeatin riboside (t-ZR) and dihydrozeatin riboside (DHZR) were analyzed by a competitive enzyme-linked immunosorbent assay. Acidification of the medium by plant, T22, and plant + T22 were assessed by three pH indicators, whereas root morphological changes were observed by light and epifluorescence microscopic analysis. The results showed that after T22-inoculation, IAA in leaves and roots significantly increased by 148 and 122%, respectively, whereas DHZR decreased by 83%. Increases in t-ZR were found only in leaves (88%). The ratios auxin/cytokinins changed from 28.5 to 46.6 in leaves, and from 15.0 to 21.2 in roots of un-inoculated and T22-inoculated plants, respectively. Root activity determined a decline of medium acidity, and this effect was more marked in T22-inoculated plants (up to pH 4). Microscopic analysis revealed changes in root cell wall suberification in the exoderm and endoderm, with an increase in suberized cellular layers from 1 to 2–3, and an enhancement of cell wall epifluorescence. During the acclimatisation phase of nursery processes, all these T22-induced changes constitute an advantage, as inoculated plants could acclimatise better, so increasing plant survival in the absence of pesticides.

Direct effects of Trichoderma harzianum strain T-22 on micropropagated GiSeLa6® (Prunus cerasus x Prunus canescens) rootstocks

SOFO, Adriano;TATARANNI, GIUSEPPE;XILOYANNIS, Cristos;DICHIO, Bartolomeo;SCOPA, Antonio
2012

Abstract

Trichoderma harzianum strain T-22 (T22) has the ability of enhancing root growth and plant development. The aim of this research is to explain the biochemical basis of the direct plant-growth-promoting activity of T22. Seven days after the transfer to root-inducing medium, in vitro-cultured shoots of GiSeLa6® (Prunus cerasus × Prunus canescens), an important Prunus rootstock for sweet and sour cherry varieties, were inoculated with T22. Indole-3-acetic acid (IAA), trans-zeatin riboside (t-ZR) and dihydrozeatin riboside (DHZR) were analyzed by a competitive enzyme-linked immunosorbent assay. Acidification of the medium by plant, T22, and plant + T22 were assessed by three pH indicators, whereas root morphological changes were observed by light and epifluorescence microscopic analysis. The results showed that after T22-inoculation, IAA in leaves and roots significantly increased by 148 and 122%, respectively, whereas DHZR decreased by 83%. Increases in t-ZR were found only in leaves (88%). The ratios auxin/cytokinins changed from 28.5 to 46.6 in leaves, and from 15.0 to 21.2 in roots of un-inoculated and T22-inoculated plants, respectively. Root activity determined a decline of medium acidity, and this effect was more marked in T22-inoculated plants (up to pH 4). Microscopic analysis revealed changes in root cell wall suberification in the exoderm and endoderm, with an increase in suberized cellular layers from 1 to 2–3, and an enhancement of cell wall epifluorescence. During the acclimatisation phase of nursery processes, all these T22-induced changes constitute an advantage, as inoculated plants could acclimatise better, so increasing plant survival in the absence of pesticides.
File in questo prodotto:
File Dimensione Formato  
Sofo et al - EEB 2012.pdf

non disponibili

Tipologia: Altro materiale allegato
Licenza: DRM non definito
Dimensione 807.95 kB
Formato Adobe PDF
807.95 kB Adobe PDF   Visualizza/Apri   Richiedi una copia

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: http://hdl.handle.net/11563/19564
 Attenzione

Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo

Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 34
  • ???jsp.display-item.citation.isi??? 26
social impact