Role of plant antiviral defense during VIGS in plant
D. SINGH (1) (1) Samuel Roberts Noble Foundation, India

We are studying antiviral defense of sorghum and cassava. Expression of Dicer-like (DCL), RNA Dependent RNA Polymerase (RDRP), and Argonaute (AGO) gene families increased significantly in sorghum plants kept at colder (18°C) and hotter (28°C) compared to ambient (22°C) temperature for one - three days. The increased expression of antiviral defense-related genes at higher temperature is consistent with reduced viral disease at a higher temperature. However, our study indicates that the susceptibility of the plants to viruses at colder temperature is not due to lower antiviral defense. This study indicates an unknown mechanism as the cause of increased susceptibility of plants to viruses at low temperature. Also, we have established an efficient VIGS method for sorghum. Brome mosaic virus based VIGS system is better compared to Barley stripe mosaic virus-based vector system as the latter cannot infect sorghum. Our study suggests that the 18°C and antisense strand of the gene of interest are critical to silence a gene in sorghum. Further, we also report increased Africa cassava mosaic virus (ACMV)-based VIGS of cassava at low temperature. Interestingly, the silencing phenotype can be transferred through shoot cuttings because ACMV was able to infect the meristem. This is first study demonstrating ACMV infection of plant meristem. Our study will shed light on the role of plant antiviral defense mechanism to improve the efficiency of VIGS in cassava and sorghum.

Abstract Number: P17-612
Session Type: Poster