Laboratory Screening of Control Agents Against Isolated Fungal Pathogens Causing Postharvest Diseases of Pitaya in Guizhou, China

Abstract

Pitaya, or dragon fruit, is a typical tropical fruit with an appealing taste and diverse health benefits to humans. The plantation of pitaya in Guizhou province in China has greatly boosted the income of local farmers and alleviated poverty. However, the frequent occurrence of postharvest diseases has brought large economic loss. To find a solution, we set out to identify the postharvest disease-causing agents of Guizhou pitaya. Several fungi were isolated from diseased pitaya and identified as species based on the ITS1 sequence similarity. Of them, Penicillium spinulosum, Phoma herbarum, Nemania bipapillata, and Aspergillus oryzae were, for the first time, found to cause dragon fruit disease. In consideration of their prevalence in postharvest fruit diseases, Alternaria alternata H8 and Fusarium proliferatum H4 were chosen as representative pathogens for the drug susceptibility test. Among the tested drugs and plant extracts, 430 g/L tebuconazole and 45% prochloraz were found to be the most potent fungicides against H8 and H4, respectively. The research provides insights into the mechanism and control of postharvest diseases of dragon fruits in Guizhou, China, and thus could be of economic and social significance to local farmers and the government.

Characterization and In Vitro Fungicide Sensitivity of Two Fusarium spp. Associated with Stem Rot of Dragon Fruit in Guizhou, China

“…Over the past two decades, the expansion of dragon fruit cultivation in Guizhou Province has led to a significant escalation in the severity of stem rot. Fusarium proliferatum was identified as the fungal pathogen of postharvest diseases on dragon fruits [6]. In this study, although a total of twenty-four fungal isolates were obtained from the infected dragon fruit samples, only two isolates of H-4 and H-5 were confirmed to be real pathogens based on Koch's postulates.…”

“…In 2020, the cultivated area in Guizhou Province exceeded 6700 ha, and its output reached 80,000 tons, ranking among the highest in China [5]. However, the expansion of cultivation areas, coupled with rising temperatures and increased rainfall, has led to a notable surge in the occurrence of fungal diseases affecting dragon fruit in Guizhou, ultimately affecting their economic benefits [6,7].…”

Identification of common fungal pathogens of dragon fruit (Hylocereus undatus) in Sarangani Province, Philippines

“…One species of the genus, Aspergillus flavus, has been identified as a post-harvest fungal pathogen of dragon fruit, which causes fruit decay (Yao et al 2022). Moreover, A. oryzae has been identified as post-harvest fungal pathogen of dragon fruit in China (Li et al 2022).…”

Advances in the Understanding of Postharvest Physiological Changes and the Storage and Preservation of Pitaya

“…According to [71], the growth of Streptomyces sp. in pitaya was inhibited, and the incidence of black rot was reduced by 10% phenyl ether metronidazole, 430 g/L tebuconazole, and 3% mesocarbamate [75].…”