How are olive and almond branches processed?

It was on a beautiful sunny Thursday that a team from the New Biopesticides Department, involved in the XfSTOP project, went to Herdade do Álamo de Cima, belonging to the Eugénio de Almeida Foundation, near Évora, and returned with a car full of olive and almond branches.

And it wasn't, of course, for the pleasure of pruning trees. The aim was to collect samples of two crops that are very important to the local agricultural economy, and which are targets of the nefarious bacterium Xylella fastidiosa, for which InnovPlantProtect intends to develop a new biopesticide.

The researchers collected samples from four varieties of olive tree - Cobrançosa, Arbequina, Galega and Picual - and four varieties of almond tree - Solena, Guara, Belona and Avijor. This work will make it possible to isolate bacterial endophytes common to olive and almond trees.

The following day, Friday, the team processed the samples. They began by cutting branches about 15-20 cm long, removing the bark, disinfecting the outside of the branch to eliminate epiphytic microorganisms and macerating the xylem vessels with a buffer solution. This solution is then filtered through special bags, diluted, plated on culture medium and placed in an incubator at 30 ºC for around 15 days. Throughout this period, the appearance of colonies is monitored.