Confirmation of Proteins Encoding Genes Important in Bacterial Wilt Resistance

Background and Aim: Bacterial wilt caused by Ralstonia solanacearum is one of the most important soil borne plant pathogenic bacteria globally imparts decrease in crop yield per year. Situation can be improved by exploring defense mechanism against bacterial wilt. Aim of study was to confirm the expression of some defense genes differentially expressed in bacterial wilt resistant in comparison to medium resistant varieties.

Place and Duration of Study: Study was done in Department of Biochemistry and Molecular Biology, University of Gujrat Pakistan for one year.

Study Design: RNA extraction followed by cDNA synthesis was done following salicylic acid (SA) (1 mM) application on Solanum lycopersicum var. Roma (medium resistant) and Riogrande (resistant variety) for three consecutive days. Expression analysis studies of iron ATP-binding cassette (ABC) transporters, ATP synthase and chaperonin was done using RT-PCR along with measurement of antioxidants enzyme activities.

Results: In control Iron ABC transporter and ATP synthase were expressed in both varieties though chaperonin was expressed in Roma only. Iron ABC transporter was expressed in both varieties within 1st day; while chaperonin was expressed after two and three days of SA treatment in Roma and Riogrande respectively. ATP synthase was expressed after one and three days of SA treatment in Roma and Riogrande respectively. Peroxidase and catalase activity increased in both varieties after one and three days more prominently in Riogrande; with little decrease after two days of SA treatment.

Conclusion: Differential expression of ATP synthase and chaperonin in response to SA in resistant and medium resistant varieties of tomato signifies importance of these genes in response to bacterial wilt in tomato.