CaLTP2 promotes suberin deposition and positively regulates Capsicum annuum defense against Meloidogyne incognita

• 1、Hunan University,College of biology,Changsha 410012

Abstract：Non-specific lipid transfer proteins (LTPs) play critical roles in the construction of suberin barriers and disease resistance; however, their functions in defense against plant-parasitic nematodes remain largely unexplored. In this study, we characterized the Capsicum annuum gene CaLTP2 using a combination of virus-induced gene silencing(VIGS), subcellular localization, histochemical staining, quantitative PCR, and nematode infection phenotyping to investigate its function and mechanism in defense against Meloidogyne incognita. The results showed that M. incognita infection significantly induced the expression of CaLTP2. Silencing of CaLTP2 significantly increased the number of nematodes and galls per root. CaLTP2 was localized to the plasma membrane and cell wall, consistent with the distribution pattern of suberin. Knockdown of CaLTP2 significantly reduced suberin deposition in roots and suppressed the expression of suberin biosynthesis-related genes, including CaFAR4, CaFAR5, CaCYP86A1, and CaCYP86B1, which were induced upon nematode infection. These findings suggest that CaLTP2 likely promotes suberin formation to regulate plant defense against root-knot nematodes.

Keywords： Botany Root-knot nematode Non-specific lipid transfer proteins Suberin CaLTP2