Defense Strategies Against Biotic Stresses in Wheat: Molecular and Physiological Approaches

Öz

Wheat is a major staple crop whose growth and yield are substantially constrained by biotic stress factors. The defense mechanisms of wheat against biotic stresses are generally categorized into pre-existing (constitutive) and induced (inducible) defense strategies. Constitutive defenses comprise physical barriers (cuticle, cell wall) and chemical compounds (such as phenolic compounds and phytoalexins), whereas induced defenses encompass dynamic responses including pathogen recognition, the hypersensitive response (HR), systemic acquired resistance (SAR), and the regulation of plant defense hormones. To enhance wheat resilience to biotic stresses, breeding programs, biotechnological approaches and integrated disease management strategies are widely employed. Gene-editing tools such as CRISPR/Cas9 offer the potential to develop resistant cultivars, while sustainable agricultural practices also play a critical role in the management of diseases and pests. In this context, the present study examines the defense mechanisms of wheat against biotic stresses and suggests that future research aimed at a deeper understanding of wheat immune pathways will contribute to the development of more resilient and high-yielding cultivars, thereby supporting global food security.

Anahtar Kelimeler

• Wheat
• biotic stress
• genetic breeding
• biotechnology
• systemic resistance

Buğdayda Biyotik Streslere Karşı Savunma Stratejileri: Moleküler ve Fizyolojik Yaklaşımlar

Öz

Buğday, biyotik stres faktörleri nedeniyle büyüme ve verim kaybı yaşayabilen temel bir tarım ürünüdür. Buğdayın biyotik streslere karşı savunma mekanizmaları, önceden var olan (konstitütif) ve uyarılmış (indüklenmiş) savunma stratejileri olarak ikiye ayrılmaktadır. Konstitütif savunmalar, fiziksel bariyerler (kutikula, hücre duvarı) ve kimyasal bileşiklerden (fenolik bileşikler, fitoaleksinler) oluşurken, uyarılmış savunmalar patojen tanıma, hipersensitif tepki (HR), sistemik edinilmiş direnç (SAR) ve bitkisel savunma hormonları gibi dinamik tepkileri içermektedir. Buğdayın biyotik streslere karşı dayanıklılığını artırmak için genetik ıslah, biyoteknolojik yaklaşımlar ve entegre hastalık yönetimi stratejileri uygulanmaktadır. CRISPR/Cas9 gibi gen düzenleme teknikleri ile dirençli çeşitler geliştirilebilirken, sürdürülebilir tarım uygulamaları da hastalık ve zararlı kontrolünde önemli rol oynamaktadır. Bu doğrultuda araştırmamızda buğdayın biyotik streslere karşı savunma mekanizmaları ele alınmış ve gelecekte yapılacak araştırmalar, buğdayın bağışıklık mekanizmalarının daha iyi anlaşılmasını sağlayarak, küresel gıda güvenliği açısından daha dayanıklı ve verimli çeşitlerin geliştirilmesine katkıda bulunacağı düşünülmüştür.

Anahtar Kelimeler

• Buğday
• biyotik stres
• genetik ıslah
• biyoteknoloji
• sistemik direnç

Kaynakça

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