PEPPER PLANTS RESPOND DIFFERENTLY TO TOMATO SPOTTED WILT VIRUS INFECTION UNDER DISTINCT IRRIGATION LEVELS

Aslan Z., Sökmen M., Gülser C.

77 th International Symposium on Crop Protection – May 19, 2026, Ghent, Belçika, 19 Mayıs 2026, ss.23, (Özet Bildiri)

  • Yayın Türü: Bildiri / Özet Bildiri
  • Basıldığı Şehir: Ghent
  • Basıldığı Ülke: Belçika
  • Sayfa Sayıları: ss.23
  • Ondokuz Mayıs Üniversitesi Adresli: Evet

Özet

Global warming and the inefficient use of water resources in agricultural production have led to significant negative consequences, including water shortage, drought, and salinity. The objective of this study is to investigate the effects of virus infection on pepper (Capsicum annum L.) under deficient- and well-irrigation conditions. Pepper seedlings were grown in a medium containing a mixture of perlite and peat (1:4; w:w) at constant temperatures of 25 °C and 20 °C (light/dark) under irrigation with 70% and 30% of the maximum water-holding capacity for nine weeks. A resistance-breaking isolate (RB-Twv) of tomato spotted wilt virus (TSWV) was used to inoculate pepper seedlings after two weeks of transplanting. Water consumption (ET), total biomass, water use efficiency (WUE), turgidity, and chlorophyll content of pepper plants were analysed at the end of the experiment. The DAS-ELISA method was applied to confirm TSWV infection in inoculated plants. Under well-irrigation (70%), non-inoculated (healthy) plants had a total biomass 40% higher than that of infected plants. Under deficient irrigation (30%), both healthy and infected plants experienced a more pronounced decline in total biomass. However, the total biomass of infected plants was greater than that of healthy plants (p<0.01) in the case of limited water. ET values dropped significantly under deficient irrigation (p<0.01), regardless of viral infection. In contrast, in well-watered treatments, the ET values of healthy plants were higher than those of infected plants. In addition, infected plants had the highest WUE in water-deficient conditions; however, their WUE decreased by up to 50% (p <0.01) when provided with adequate watering. However, in both irrigation treatments, healthy plants exhibited higher proportional turgidity, suggesting better water retention, which correlates with high turgor pressure in the leaf cells of these plants. Healthy plants had an average chlorophyll level of 0.121 mg/g under well-watered conditions, significantly lower than the 0.256 mg/g observed in infected plants. Under water-stressed conditions, the mean chlorophyll contents of infected plants were 0.68 mg/g in healthy plants and 0.74 mg/g in infected ones. Virus infection appears to boost total chlorophyll levels in plants, notably more under full-irrigation treatment. The detrimental effect of the deficient irrigation on ET values could be associated with the closure of stomata to inhibit water loss. Infected plants exhibited significantly higher total chlorophyll contents in both irrigation levels. The results of chlorophyll assessments and our phenotypic observations confirmed that full irrigation accelerated the plant’s senescence, which may potentially affect chlorophyll content.