LAUSR

To study the changes in sugar metabolism caused by fungal infection in post-harvest peaches, fruit from two cultivars (‘Baifeng’ and ‘Yulu’) was inoculated with Monilinia fructicola and stored at 10 °C. During disease development, soluble sugar content was monitored, as well as the activities and expression of selected enzymes. Disease progression was accompanied by a decrease in sucrose content and increases in reducing sugars and soluble solids, consistent with higher enzyme activities for acid invertase, neutral invertase and sucrose synthase-cleavage, and lower activities for sucrose synthase-synthesis and sucrose phosphate synthase. Activities of phosphofructokinase, hexokinase, and pyruvate kinase, which are related to hexose metabolism, also increased. These changes stimulate the Embden–Meyerhof–Parnas (EMP) pathway. We conclude that the fungal disease in peach fruit accelerates the decomposition of sucrose, thereby providing more glucose as a substrate to the EMP pathway.Fruit fungal infection: Effects on sugar metabolismA study by researchers in China provides insights into changes to sugar metabolism during fungal infection in post-harvest peaches. Fungal infections and associated disease development can alter sugar metabolism in post-harvest fruits, leading to rapid decay and a short shelf life. However, little is known about the mechanisms behind these fungal infections. Xingfeng Shao and Yingying Wei at Ningbo University and co-workers examined the effect of brown rot, caused by a fungus called Monilinia fructicola, on sugar metabolism in two peach cultivars kept under chilled conditions. As the disease progressed, the fruit increased its energy supply by decomposing sucrose and generating more glucose. The team uncovered the major enzymes responsible for this sucrose decomposition. The increased glucose stimulated the Embden-Meyerhof-Parnas pathway, which in turn helped the peaches fight infection.