"It would be the first time that olive branches are not distributed during (Easter) Holy Week, but it is a decision that must be taken to prevent the spread of the disease to millions of healthy trees," said Roberto Moncalvo, the head of the agricultural group Coldiretti.
Catholic officials said no orders had been issued regarding the blessing of olive branches in churches on the Sunday before Easter, but media reports indicated that individual dioceses had taken steps to ensure none came from the Lecce area of the southern region of Puglia, which has been worst affected by the bacteria.
Producers and authorities in Lecce are battling an epidemic of xylella fastidiosa, a strain of bacteria causing olive and other plants to wither away.
More than one million trees - some of them centuries old - have been infected and may have to be destroyed.
According to Christian tradition, Palm Sunday marks the day Jesus Christ entered Jerusalem prior to his crucifixion, when palm branches were scattered in his path by people who had come to greet him.
Palms are still used to commemorate the moment in many Churches in the Middle East, but they have been substituted for more readily available foliage in Europe.