Title : Protein profiling of pigeonpea root infected with Fusarium udum

Abstract:

Pigeonpea, a drought-tolerant crop in India, is vulnerable to over 100 pathogens, including fungi, bacteria, viruses, nematodes, and phytoplasma. Management of soil born diseases such as fusarial wilts is challenging due to limitations of using chemical fungicides. Use of resistant varieties is ideal but often challenged by evolution of new variants of pathogens. This research aims to explore root proteome responses, identify host plant proteins for resistant cultivars, and understand the molecular mechanisms of pigeonpea and F.udum interactions.

The study analyzed pigeonpea Fusarium wilt-susceptible (ICP 2376) and resistant (ICP 9174) genotypes for proteomics. Seeds were grown in a greenhouse, and the pathogen was multiplied on potato dextrose broth. Seedlings were uprooted, washed, and cut off to facilitate entry. Total protein extraction was performed on both genotypes, and two-dimensional gel electrophoresis was performed on pigeonpea root protein. Proteins were identified by a combined search of PMF and MS/MS data against the taxonomy of Viridiplantae. The purpose is to understand the molecular mechanisms governing plant susceptibility and resistance. In the interaction between pigeonpea and F. udum, 141 differentially expressed protein spots were recorded, with 12 successfully characterized.

Seven differentially expressed proteins were identified in the resistant cultivar, and were classified into seven functional categories based on their biological functions. To comprehend pigeonpea's defense mechanisms against Fusarium udum infection, proteome profiles revealed that two proteins R56 (pathogenesis-related protein) and S41 (protein P21/Thaumatin-like protein) are part of the defense mechanism of pigeon peas. Whereas down-regulation of S41 in susceptible cultivars supports direct defense, greater accumulation of R56 in resistant cultivars suggests F. udum-induced defense.