ICP-MS-based leaf ionomics study in tomato varieties infected with Fusarium oxysporum f. sp. lycopersici (Fol)

Abstract

Tomato (Solanum lycopersicum L.) is widely cultivated worldwide; however, Fusarium wilt, caused by Fusarium oxysporum f. sp. lycopersici (Fol), remains one of the major diseases affecting tomato production. Because mineral elements can influence plant defence and pathogen colonization, leaf ionomic profiling may provide useful information on host responses during plant-pathogen interactions. This study aimed to analyze leaf ionomes and identify physiological adaptations in tomato plants during the Fol interaction across resistant, moderately resistant, and susceptible varieties. Leaves from inoculated and uninoculated plants were collected at 0 days before inoculation (0 DBI; pre-infection baseline) and at 7, 14, and 21 days after inoculation (DAI), and were analyzed by inductively coupled plasma-mass spectrometry (ICP-MS). The results showed that phosphorus, potassium, calcium, and boron concentrations were generally higher in resistant varieties than in susceptible varieties before and after inoculation. In contrast, iron concentration was higher in susceptible varieties and declined markedly after Fol infection, especially in susceptible genotypes. Principal component analysis further separated resistant and susceptible varieties on the basis of their elemental profiles. These differences in leaf ionome composition suggest that mineral nutrient status is associated with tomato response to Fusarium wilt and may contribute to the resilience of resistant varieties.