N‐acetylcysteine absorption and its potential dual effect improve fitness and fruit yield in Xylella fastidiosa infected plants

Abstract

AbstractBACKGROUNDXylella fastidiosa is a multi‐host bacterium that can be detected in hundreds of plant species including several crops. Diseases caused by X. fastidiosa are considered a threat to global food production. The primary method for managing diseases caused by X. fastidiosa involves using insecticides to control the vector. Hence, it is necessary to adopt new and sustainable disease management technologies to control not only the insect but also the bacteria and plant health. We demonstrated that N‐acetylcysteine (NAC), a low‐cost cysteine analogue, is a sustainable molecule that can be used in agriculture to decrease the damage caused by X. fastidiosa and improve plant health.RESULTSUsing 15N‐NAC we proved that this analogue was absorbed by the roots and transported to different parts of the plant. Inside the plant, NAC reduced the bacterial population by 60‐fold and the number of xylem vessels blocked by bacterial biofilms. This reflected in a recovery of 0.28‐fold of the daily sap flow compared to health plants. In addition, NAC‐treated citrus variegated chlorosis (CVC) plants decreased the oxidative stress by improving the activity of detoxifying enzymes. Moreover, the use of NAC in field conditions positively contributed to the increase in fruit yield of CVC‐diseased plants.CONCLUSIONOur research not only advances the understanding of NAC absorption in plants, but also indicates its dual effect as an antimicrobial and antioxidant molecule. This, in turn, negatively affects bacterial survival while improving plant health by decreasing oxidative stress. Overall, the positive field‐based evidence supports the viability of NAC as a sustainable agricultural application. © 2024 Society of Chemical Industry.