Expression of Immune System Genes in Tomato Plants Infected by Meloidogyne Incognita

Data were presented from a study on expression of resistance gene Mi-1.2 of protective genes of the PR gene family (PR-2, PR-3) and genes of serine and cysteine proteinase (PIser PIcys) inhibitors in tissues of tomato plants of resistant and susceptible hybrids infected by gall nematodes and an assessment of their role in parasite resistance was given. Differences were detected in the expression of the studied genes at all stages of nematode development in the roots of resistant and susceptible plants. The studies showed that the infection of resistant plants caused an increase in the study gene transcripts as early as in the initial period of infection, which indicated the response time to nematode larvae penetration and the speed of adequate protective response. Changes in the defense response-related gene expression in infected susceptible plants were insignificant and appeared after the larvae penetrated the roots, which may be one of the reasons for disease progress. The increased expression of the studied genes that encode protective proteins in infected roots of resistant plants found at all parasite development stages indicates the importance of protective proteins in tomato plant resistance to gall nematode.