Biology subjects

Boruah, L.

Publications and source records attributed to Boruah, L..

2 recordsLinked to original sources

bioRxiv2024

Tissue-independent nature of plant susceptibility: a comparative pathogenicity study of the systemic phytopathogen Ralstonia pseudosolanacearum in eggplant and tomato seedlings through root and leaf

Ralstonia pseudosolanacearum causes a lethal bacterial wilt disease in many plant species, posing significant economic challenges. Although tomato has been a primary model host for investigating the pathogenicity and systemic infection of this bacterium, this manuscript presents a comparative pathogenicity study between two closely related solanaceous hosts, tomato and eggplant, revealing differential host responses to the same pathogen, specifically through leaves and roots. Interestingly, eggplant seedlings exhibited a significantly higher susceptibility to cotyledon leaf inoculation than tomato seedlings. In the case of tomato, a few seedlings escaped wilting (called escapees), which was usual at a high pathogen load, unlike the case of eggplant seedlings where escapees could not be observed even at a 100-fold lower pathogen concentration. The greater susceptibility of eggplant was further demonstrated by performing both single- and double-leaf inoculations in the seedlings. Surprisingly, root inoculations resulted in a significantly lower mortality for eggplant than for tomato seedlings. The contrasting susceptibility between the two hosts regarding root and leaf regions indicates the tissue-dependent nature of susceptibility. The study underscores the value of employing multiple host species to uncover new insights into pathogen behaviour and host-pathogen interactions.

pathology↗

bioRxiv2024

Morphology of softening and translucency in the stems of tomato and eggplant seedlings due to infection by Ralstonia pseudosolanacearum F1C1

Ralstonia pseudosolanacearum F1C1 is a soil-borne phytopathogenic bacterium with a broad host range that infects several economically important crops. This study primarily focuses on the infection of this phytopathogen in two such important crop seedlings: tomato and eggplant. The observations of the study reveal a complex set of symptoms that include drooping and blackening of the seedling stem, as well as blackening, chlorosis, and curling of cotyledon leaves. Notably, the symptom of stem softening and translucency is seen primarily in the water-submerged stem regions of both root- and leaf-inoculated seedlings. While the wild-type R. pseudosolanacearum F1C1 strain and its weakly virulent mutant phcA::{Omega} exhibited this phenotype in both tomato and eggplant seedlings, the virulence-deficient hrpB::{Omega} mutant did so only in a few eggplant seedlings but not in tomato seedlings. By investigating these unique pathological phenotypes in the infected seedlings, this study uncovers a unique symptom previously not reported in seedling inoculation experiments. The work also touches upon the distinct escape mechanisms exhibited by seedlings, revealing how some of its host plants might resist wilting despite infection, offering new avenues for future research. These findings contribute to the understanding of R. pseudosolanacearum pathogenesis, shedding light on its virulence and host response mechanisms.

plant biology↗