R. Dragov*, D. Dechev Field Crops Institute, 6200 Chirpan, Bulgaria Abstract. The yield is a key indicator in the plant breeding of crops. In recent years a number of new durum wheat varieties created in Field Crops Institute, Chirpan, Bulgaria, have been certified, which are prerequi

The genotype × environment interaction and stability of five cotton varieties were studied during 2002-2006. The years of the investigation appeared to be as different ecological environments. The stability variances (2i and S2i) of Shukla (1972) and YSi index of Kang (1993) were calc