The GRAS Salts of Na<sub>2</sub>SiO<sub>3</sub> and EDTA-Na<sub>2</sub> Control Citrus Postharvest Pathogens by Disrupting the Cell Membrane
Juan Zhao,
Yuqing Wang,
Qianyi Liu,
Shuqi Liu,
Hui Pan,
Yunjiang Cheng,
Chaoan Long
Affiliations
Juan Zhao
National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, National R&D Center for Citrus Preservation, National Centre of Citrus Breeding, Huazhong Agricultural University, Wuhan 430070, China
Yuqing Wang
National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, National R&D Center for Citrus Preservation, National Centre of Citrus Breeding, Huazhong Agricultural University, Wuhan 430070, China
Qianyi Liu
National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, National R&D Center for Citrus Preservation, National Centre of Citrus Breeding, Huazhong Agricultural University, Wuhan 430070, China
Shuqi Liu
National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, National R&D Center for Citrus Preservation, National Centre of Citrus Breeding, Huazhong Agricultural University, Wuhan 430070, China
Hui Pan
National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, National R&D Center for Citrus Preservation, National Centre of Citrus Breeding, Huazhong Agricultural University, Wuhan 430070, China
Yunjiang Cheng
National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, National R&D Center for Citrus Preservation, National Centre of Citrus Breeding, Huazhong Agricultural University, Wuhan 430070, China
Chaoan Long
National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, National R&D Center for Citrus Preservation, National Centre of Citrus Breeding, Huazhong Agricultural University, Wuhan 430070, China
Sodium silicate (Na2SiO3) and ethylenediaminetetraacetic acid disodium salt (EDTA-Na2) are inorganic salts classified as ‘Generally Recognized as Safe’ (GRAS) compounds with great advantages in controlling various pathogens of postharvest fruits and vegetables. Here, we determined the median effective concentration (EC50) of Na2SiO3 (0.06%, 0.05%, 0.07% and 0.08%) and EDTA-Na2 (0.11%, 0.08%, 0.5%, and 0.07%) against common pathogens affecting postharvest citrus fruit, including Penicillium digitatum, Penicillium italicum, Geotrichum citri-aurantii, and Colletotrichum gloeosporioides. Na2SiO3 and EDTA-Na2 treatments at the EC50 decreased the spore germination rate, visibly disrupted the spore cell membrane integrity, and significantly increased the lipid droplets (LDs) of the four postharvest pathogens. Moreover, both treatments at EC50 significantly reduced the disease incidence of P. italicum (by 60% and 93.335, respectively) and G. citri-aurantii (by 50% and 76.67%, respectively) relative to the control. Furthermore, Na2SiO3 and EDTA-Na2 treatment resulted in dramatically lower disease severity of the four pathogens, while also demonstrating no significant change in citrus fruit quality compared with the control. Therefore, Na2SiO3 and EDTA-Na2 present a promising approach to control the postharvest diseases of citrus fruit.
