Sweet cherry tree prioritizes water stress response over pathogen defense

11 Sep 2024
1380

A recent study conducted by Chilean and Spanish researchers analyzed the delicate balance that sweet cherry trees must manage between responding to drought conditions and defending against pathogens like Pseudomonas syringae pv. syringae (Pss). The study focuses on the cultivars “Bing” and “Santina”, and how they allocate their resources when faced with stressful situations.

Climate change is increasingly subjecting crops to a range of environmental stresses, with drought and pathogen attacks being the most significant. For sweet cherry trees, this dual challenge is particularly important. Pss is known to cause bacterial canker, a disease that can devastate sweet cherry orchards. However, the study shows that during the hot and dry summer months, the plants' need to conserve water overcomes their efforts to mount a defense response against Pss.

The study's results indicate that “Santina” cultivar exhibited a stronger initial response to Pss compared to “Bing.” However, both cultivars, when also subjected to summer drought, showed a change in their physiological responses. The plants reduced their leaf area and transpiration rates, thus conserving water and maintaining hydraulic functionality at the expense of a robust defensive response against Pss.

Under good water availability, the “Santina" cultivar inoculated with Pss showed a significant reduction in leaf growth and transpiration. However, when water was limited, both “Bing” and “Santina” cultivars showed a decrease in gas exchange and biomass production, regardless of Pss inoculation. This highlights the importance of water management for plant survival under water stress, even if it may compromise the level of defense against pathogens.

A key factor in this prioritization process is the interaction between two plant hormones: abscisic acid (ABA) and salicylic acid (SA). ABA is crucial for regulating the plant's response to water stress, particularly by closing stomata to reduce water loss. On the other hand, salicylic acid is involved in the plant's defense against pathogens.

The study showed that under good irrigation conditions, SA levels were higher in Pss-inoculated plants, supporting the defensive response. However, under water-deficit conditions, ABA levels increased while SA levels decreased, shifting the plant's priority towards drought resistance over pathogen defense.

This trade-off has significant implications for the management of sweet cherry orchards, particularly in regions prone to drought, where it is necessary to address water stress during the critical hot months.

In conclusion, the study shows how sweet cherry trees "prioritize" physiological responses based on environmental conditions. When plants face multiple threats such as drought and pathogen attacks, they tend to favor survival through water conservation over disease defense mechanisms. This research helps to better understand the stress responses of sweet cherry trees, providing useful information for fruit growers and nurseries.

Source: Villalobos-González, L.; Carreras, C.; Beltrán, M.F.; Figueroa, F.; Rubilar-Hernández, C.; Opazo, I.; Toro, G.; Salvatierra, A.; Sagredo, B.; Pizarro, L.; et al. Sweet Cherry Plants Prioritize Their Response to Cope with Summer Drought, Overshadowing the Defense Response to Pseudomonas syringae pv. syringae. Plants 2024, 13, 1737. https://doi.org/10.3390/plants13131737.
Image: Gonzales et al.

Andrea Giovannini
University of Bologna (IT)


Cherry Times - All rights reserved

What to read next

German study reveals how to increase fruit set through synergy between mason bees and honeybees

Tech management

17 Aug 2023

This study examined the relationship between stocking rates and honeybee and mason bee abundance in 17 sweet cherry orchards in central Germany. Also, an experiment was conducted to investigate the influence of mason bees and honeybees on fruit set of sweet cherry trees.

Homogenisers and caustic products: agronomic choices compared for the optimal start of the season

Tech management

19 Jun 2024

Is it a bad idea to use cyanamide and tandem with dormancy-breaking caustics? This is an unfriendly strategy, but highly recommended in years with low cold accumulation and in variety/ rootstock combinations that give precocity and are found in early areas.

In evidenza

Drosophila suzukii in France: winter fruits reveal new control strategies

Crop protection

12 Sep 2025

A study in France explores the effects of ornamental winter fruits on Drosophila suzukii, an invasive pest damaging soft fruit crops. Researchers tested thermal regimes to evaluate survival, reproduction, and potential strategies for biological control and prevention.

How cherries in Patagonia survived frosts down to minus 9 degrees

Tech management

12 Sep 2025

Frosts as low as -9°C did not affect cherry production in Patagonia thanks to sprinkler irrigation systems that protect flowers and buds. The Cherry Growers’ Chamber reassures: no damage to crops, but targeted investments are needed to face extreme weather events.

Tag Popolari