Isı stresi altındaki biber (Capsicum annuum L.) bitkilerinde sodyum nitroprussid (SNP) uygulamasının oksidatif hasar üzerine etkileri

Abstract

Isı stresi, tarımsal üretimde bitki büyümesini ve verimliliğini sınırlayan önemli bir abiyotik stres faktörüdür. Nitrik oksit (NO) donörü olan sodyum nitroprussit (SNP), bitkilerde abiyotik stres yanıtlarının düzenlenmesinde rol oynayan bir bileşiktir. Bu çalışmada, yüksek sıcaklık koşullarında yetiştirilen Capsicum annuum L. fidelerinde SNP uygulamasının büyüme parametreleri, toplam klorofil içeriği ve oksidatif stres göstergeleri üzerindeki etkileri araştırılmıştır. Bitkiler 25 °C (kontrol) ve 38 °C (ısı stresi) koşullarında yetiştirilmiş ve 50 ile 100 µM SNP uygulanmıştır. Bulgular, ısı stresinin büyüme parametreleri ve toplam klorofil içeriğini azalttığını; lipid peroksidasyonu (MDA) ve hidrojen peroksit (H₂O₂) birikimini ise artırdığını göstermiştir. Isı stresinin katalaz (CAT) aktivitesini artırdığı belirlenmiştir. Isı stresi koşullarında 50 µM SNP uygulaması MDA ve H₂O₂ düzeylerini azaltarak oksidatif hasarı hafifletirken, 100 µM SNP bu parametreleri artırmıştır. SNP uygulamasının CAT aktivitesini dozuna bağlı olarak baskıladığı belirlenmiştir. Bu sonuçlar, SNP’nin ısı stresi altında Capsicum annuum L. fidelerinde doza bağlı fizyolojik ve biyokimyasal yanıtlar oluşturduğunu ve uygun dozlarda uygulandığında ısı stresinin olumsuz etkilerinin hafifletilmesine katkı sağlayabileceğini göstermektedir. Elde edilen verilerin, sıcaklık stresi koşullarında bitkisel üretime yönelik uygun doz temelli stres yönetimi yaklaşımlarının ve sürdürülebilir tarımsal stratejilerin geliştirilmesine katkı sağlayabileceği değerlendirilmektedir.

Keywords

• Isı stresi
• Capsicum annuum. L
• Sodyum nitroprussid (SNP)
• oksidatif stres
• büyüme parametreleri

Effects of sodium nitroprusside (SNP) application on oxidative damage in pepper (Capsicum annuum L.) plants under heat stress

Abstract

Heat stress is a major abiotic factor limiting plant growth and productivity. Sodium nitroprusside (SNP), a nitric oxide (NO) donor, plays an important role in regulating plant responses to abiotic stress. This study investigated the effects of SNP application on growth parameters, total chlorophyll content, and oxidative stress indicators in Capsicum annuum L. seedlings grown under high temperature conditions. Plants were grown at 25 °C (control) and 38 °C (heat stress) and treated with 50 and 100 µM SNP. The results showed that heat stress reduced growth parameters and total chlorophyll content, while increasing lipid peroxidation (MDA) and hydrogen peroxide (H₂O₂) accumulation. Heat stress enhanced catalase (CAT) activity. Under heat stress, 50 µM SNP alleviated oxidative damage by reducing MDA and H₂O₂ levels, whereas 100 µM SNP increased these parameters. In contrast, SNP application suppressed CAT activity in a dose-dependent manner. These findings indicate that SNP induces dose-dependent physiological and biochemical responses in Capsicum annuum L. seedlings under heat stress and that appropriate SNP doses may contribute to mitigating heat stress–induced damage. The results may also support the development of dose based stress management strategies for sustainable crop production under high temperature conditions.

Keywords

• Heat stress
• Capsicum annuum. L
• sodium nitroprusside (SNP)
• oxidative stress
• growth parameters

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