Bitki Virüsleriyle Mücadelede Yeni Stratejiler: Virüs Enfeksiyonlarina ve Vektörlerine Karşi Dayanikliliğin Geliştirilmesi New Strategies in Control of Plant Viruses: Resistance Development to Virus Infections and Their Vectors

OZET: Kultur bitkilerinde kalite ve verim azalisina sebep olan virus hastaliklari mucadele zorlugu acisindan ayri bir onem tasimaktadir. Virusten ari (virussuz) uretim materyali kullanmak, viruse ve vektor organizmaya dayanik- lilik islahi ve vektor organizmalarla mucadele ederek hastaligin bulasmasini engellemek viral hastalik etmenleriy- le mucadelede en etkili yontemlerdir. Uzerinde en fazla calisilan yontem viruslere karsi dayanikli bitki genotiple- rinin gelistirilmesidir. Viruslere dayanikli cesitler, hem dogal dayaniklilik genleri iceren hatlarla ekonomik degeri olan cesitlerin tozlastirilmasi seklinde klasik islah metotlariyla hem de son yillarda, genetik muhendisligi yontem- leri kullanilarak transgenik olarak elde edilebilmektedir. Bitkileri viruslere karsi dayanikli hale getirmek icin uc te- mel transgen kaynagindan faydalanilmaktadir. Bunlar dogal dayaniklilik genleri, viral sekanslardan turetilen gen- ler (Patojen kaynakli dayaniklilik) ve diger kaynaklardan elde edilen ve hedef virusu engelleyici cesitli genlerdir. Patojen kaynakli dayaniklilik (PDR) uygulamalarinin temeli, patojenezdeki molekuler etkilesimlerin anlasilmasi ve bunlarin patojen aleyhine bozulmasidir. Hedef virusun kilif proteini (CP) geninin aktarilmasi ve transkripsiyon sonrasi gen susturulmasi (Post Transcriptional Gene Silencing) patojen kaynakli dayaniklilikta son yillarda en cok uzerinde durulan uygulamalardir. Bu derlemede bitki patojeni viruslerle mucadelede ozellikle viruslere ve vektor- lerine karsi kultur bitkilerini dayanikli hale getirme yontemleri ozetlenmektedir. Anahtar kelimeler: Virus hastaliklari, dogal dayaniklilik, patojen kaynakli dayaniklilik, kilif proteini geni ABSTRACT: Virus diseases, which decrease quality and quantity of crop yield, have importance because of the difficulties in control. The most efficient methods to control virus diseases are use of virus-free plant material, breeding resistant varieties to viruses or vectors, controlling vector organisms to prevent the viral diseases. Re- cently, development of resistant varieties became one of the prevalent methods. Besides the naturally resistant varieties, it can be obtained by classically crossing of varieties containing natural resistance genes with commercial varieties or by genetic engineering methods in two decades. There are three main trans-gene sources to obtain re- sistant transgenic plants against virus infections. Naturally resistance genes, pathogen derived resistance genes and various genes are obtained from the other sources. Pathogen derived resistance is commonly used comparing to the others. These methods are based on understanding of molecular interactions in pathogenesis and interference of these interactions against plant pathogens. The most commonly used methods are transfer coat protein (CP) gene of target virus and gene silencing (Post Transcriptional Gene Silencing). In this review, the methods for making resistant plants against viruses and vectors are summarized.