Grapevines infected with the phytoplasma 'Candidatus Phytoplasma solani' present no symptoms early in the growing season. We conducted mRNA and miRNA transcriptomic analyses to elucidate grapevine response to infection both before and after the onset of visible symptoms.

Four phytoplasma-infected grapevines (Vitis vinifera) cv. Zweigelt and their four healthy neighbors from a vineyard in Vienna (Austria) were selected for the study according to their symptom development in previous seasons. First fully developed leaves were sampled from several canes of each vine in June and September 2017 and in June 2020. In 2017 all four selected phytoplasma infected plants showed severe symptoms in September, while three out four phytoplasma infected plants recovered in 2020. Extracted mRNA and sRNA were sequenced by Illumina HiSeq 4000.