Proline Content, Total Protein, and Protein Electrophoresis Pattern in Sunflower (Helianthus annuus L.) in Response to Sclerotinia (Sclerotinia sclerotiorum) Disease

Sclerotinia is an important fungal disease of sunflower in Iran that affects its yield. The present study was conducted with the aim of evaluating proline content, total protein, and protein electrophoresis pattern in sunflower (Helianthus annuus L.) in response to sclerotinia (Sclerotinia sclerotiorum) disease. In this experimental study, proline content, total protein, and protein electrophoresis pattern in sunflower lines (C39 and C100) were compared with control group during different times after inoculation of the lines with the Sclerotinia fungal isolates (SSU107 and SSKH41) under controlled conditions and as a factorial based on completely randomized design (CRD). Separation and isolation of total proteins extracted by sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS-PAGE). The date were analyzed by SPSS 22 software, using multivariate analysis of variance and Tukey test. Resistant line C39 in all of the time periods after being infected had higher proline compared with control and other groups. The total protein of all control plants was higher than that of infected plants with both fungal isolates. Fungal infection accumulated low molecular weight proteins in both lines, so that some proteins in the resistant and some proteins in susceptible lines were produced and removed, respectively. Resistant line C39 in sunflower infected with fungal isolate SSU107 Sclerotinia sclerotiorum has the highest proline content. Fungal infection, especially in resistant lines, leads to a reduction in total protein levels and the accumulation of low molecular weight proteins in resistant and susceptible lines.