Mechanisms and management strategies for rain-cracking in greenhouse and open-air cherry

Abstract

Rain-induced cracking remains a persistent challenge in cherry (Prunus avium) cultivation, affecting both greenhouse and open-air grown varieties. This review explores and contrasts the underlying mechanisms of rain-cracking in these two cultivation environments, emphasizing key differences in water transport pathways. While rain-cracking in open-air cherries is predominantly driven by xylem water transport, greenhouse cherries are primarily affected by water absorption through the fruit epidermis. Additional distinctions include environmental influences such as calcium leaching from the pericarp and temperature drops caused by wind in open-air cherry, as well as the challenges associated with overthinning in greenhouse cultivation. To mitigate rain-cracking, this review summarizes various orchard management strategies, including crop load regulation, mineral sprays, bio-stimulants, growth regulators, anti-transpirants, edible coatings, and the air-blast sprayer integrated with field-sensing technology. Each approach is evaluated in terms of environmental suitability, efficacy, technical feasibility, and research advancements at both domestic and international levels. Furthermore, key assessment methodologies, including cracking index (CI), T50/WU50, and cracking ratio (CR), are analyzed and compared to establish a standardized framework for evaluating rain-cracking susceptibility. By providing a comprehensive synthesis of current knowledge, this review offers guidance for cherry orchard management and lays the foundation for future research on effective rain-cracking mitigation strategies across diverse cultivation conditions.