microRNAs can play a crucial role in stress response in plants, including biotic stress. Some miRNAs are known to respond to bacterial infection. This work has addressed the role of miRNAs in Manihot esculenta (cassava)-Xanthomonas axonopodis pv. manihotis (Xam) interaction. Illumina sequencing was used for analyzing small RNA libraries from cassava tissue infected and non-infected with Xam. Cassava variety MBRA685 (resistant to Xam-CIO151) Six-week-old plants were inoculated with 36h-old cultures of the aggressive Xanthomonas axonopodis pv. manihotis strain CIO151 in both leaves and stems. Overall design: Leaves were inoculated by piercing six holes in the mesophyll and placing a 5ÂµL drop of a liquid Xam-MgCl2 culture calibrated at OD600nm = 0.002 (1 x108cfu/ml). Two leaflets per leaf and three leaves per plant were inoculated. Stems were inoculated by puncture in the stems as described previously (24). At least three plants per collection time were inoculated. Leaves and stems were collected from inoculated plants (0 hours post inoculation -hpi, 6hpi, 24hpi, 2 days post-inoculation -dpi, 5dpi, 7dpi and 15dpi) and non-inoculated plants. RNA extractions were made using a LiCl-acid phenol:chloroform method.