Involvement of Ethylene in the Latex Metabolism and Tapping Panel Dryness of Hevea brasiliensis

Riza-Arief Putranto (1, 2) , Eva Herlinawati (3) , Maryannick Rio (1) , Julie Leclercq (1) , Piyanuch Piyatrakul (1, 4) , Eric Gohet (5) , Christine Sanier (1) , Fetrina Oktavia (3) , Julien Pirrello (1) , Kuswanhadi Kuswanhadi (3) , Pascal Montoro (1)

1 UMR AGAP - Amélioration génétique et adaptation des plantes méditerranéennes et tropicales
2 Indonesian Research Institute for Biotechnology and Bioindustry - IRIBB (Bogor, Indonesia)
3 Indonesia Rubber Research Institute - IRRI (Bogor, Indonesia)
4 Rubber Research Institute of Thailand - RRIT (Bangkok, Thailand)
5 UPR Système de pérennes - Performance des systèmes de culture des plantes pérennes

Ethephon, an ethylene releaser, is used to stimulate latex production in Hevea brasiliensis. Ethylene induces many functions in latex cells including the production of reactive oxygen species (ROS). The accumulation of ROS is responsible for the coagulation of rubber particles in latex cells, resulting in the partial or complete stoppage of latex flow. This study set out to assess biochemical and histological changes as well as changes in gene expression in latex and phloem tissues from trees grown under various harvesting systems. The Tapping Panel Dryness (TPD) susceptibility of Hevea clones was found to be related to some biochemical parameters, such as low sucrose and high inorganic phosphorus contents. A high tapping frequency and ethephon stimulation induced early TPD occurrence in a high latex metabolism clone and late occurrence in a low latex metabolism clone. TPD-affected trees had smaller number of laticifer vessels compared to healthy trees, suggesting a modification of cambial activity. The differential transcript abundance was observed for twenty-seven candidate genes related to TPD occurrence in latex and phloem tissues for ROS-scavenging, ethylene biosynthesis and signalling genes. The predicted function for some Ethylene Response Factor genes suggested that these candidate genes should play an important role in regulating susceptibility to TPD.

Mots clés: Abiotic stress; Antioxidant; Ethephon; Ethylene response factor; Oxidative stress; Rubber; Transcription factor

Domaines: Biologie végétale; Agronomie

Riza-Arief Putranto, Eva Herlinawati, Maryannick Rio, Julie Leclercq, Piyanuch Piyatrakul, et al.. Involvement of Ethylene in the Latex Metabolism and Tapping Panel Dryness of Hevea brasiliensis. International Journal of Molecular Sciences, 2015, 16 (8), pp.17885-17908. ⟨10.3390/ijms160817885⟩. ⟨hal-01264334⟩