Impact of plastic covers on the progression of Pseudomonas syringae pv. actinidiae and fruit productivity in a yellow-kiwifruit orchard

Abstract

This research shows the impact of the use of plastic covers on the containment of bacterial canker of kiwifruit caused by the bacterium Pseudomonas syringae pv. actinidiae (Psa), and also its effect on productivity and survival of the evaluated orchards. The study and monitoring were carried out on a total of 7890 plants of Actinidia chinensis 'Jintao', Psa+, located in Sagrada Familia commune, Maule Region, Chile, during 2015 and 2016. To determine the level of progress and evolution of the bacteria during the study period, disease symptoms were monitored through diagnostic mapping during early spring, late spring and autumn. Productivity was determined in sectors with and without plastic covers, by quantifying the weight of fruit of export quality produced per hectare. The progress and evolution of bacteria in the uncovered sector were notably higher than in the covered sector (4 vs. 40%, respectively, in the season 2016-2017), as opposed to productivity (16.216 vs. 7.252 kg ha-1, respectively in the season 2016-2017), which was notably higher in the latter. The results of this research demonstrate the potential of plastic covers as a Psa containment tool under local conditions. In addition, they suggest that this type of plastic would narrow the period of development and infection of the pathogen, due to the modification of environmental conditions, although these trials should continue to be studied and validated. Control of the disease over time would allow unproductive orchards to recover, making it possible to envisage a coexistence of the disease with high production standards.