30 Kasım 2013 Cumartesi





PATATESDE FİZYOLOJİK YAŞ VE ETKİLEYEN FAKTÖRLER

Mete Kaan BÜLBÜL

               Patates yumrusunun karmaşık bir yaşlanma süreci vardır ama fizyolojik ve biyokimyasal mekanizma tam olarak anlaşılamamıştır (Wiltshire & Cobb, 1996; Coleman, 2000). Ancak, genel olarak bir tohum kalitesi için fizyolojik yaş hayati önem taşır (Struik & Wiersema, 1999). Yetiştirme ve depolama koşullarıyla birlikte yumru oluşumunun kronoloji yaşı dahi fizyolojik yaşı etkiler (Reust, 1986; Struik & Wiersema, 1999).  

Determination of Reliable Selection Criterias for Early Generations in Potato Breedıng

 Determination of Reliable Selection Criterias for Early Generations in Potato Breedıng

Mete Kaan BÜLBÜL

ABSTRACT

              This study was conducted to evaluate the effectiveness of some visual selection criteria; and, to determine the reliable selection criteria for seedling and the first clonal generations in potato breeding programs aiming to develop of high yielding cultivars.
              The hybrid true potato seeds from eleven crossing combinations were obtained with crossing in Nevsehir during summer season in 2010. The seedlings from true seeds were grown in greenhouse in Hatay from December 2010 to March 2011 to obtain seedling generations. Then, one tuber of each seedling was planted into field in Kayseri in June 2011 to obtain the first clonal generation. In each generation, some morphological and agronomic traits, which can be used as selection criteria, were measured on each plant. A Breeder Preference Score (BPS) on 1-9 scale (1 the worst-9 the best) were also given to each plant based on their visual appearance before and after harvest. Then, the correlation coefficients were calculated between measured traits and given BPS in each generation. The correlation coefficients between BPS of seedling and the first clonal generation for each hybrid plant were also calculated.   
                 The results indicated that morphological characteristics of same plant could significantly vary between seedling and field generations. The selections for even tuber shape and eye depth may be misleading when the tuber size is very small in the seedling stage. It was concluded that the threshold level for BPS should be lower in the seedling stage due to weak correlation between BPS values of seedling and field generations.