Variation in rye (Secale cereale L.) inbred lines with different type of glaucousness

This study included 22 rye inbred lines in S5 - 6 generations and one non-glaucous strain, originated from Bulgarian rye (Secale cereale L.) accession A9E1389. Variation in plant height, heading date, self- and open-fertility was recorded to characterize the inbred lines in two growing seasons. Plant height varied between 85 and 124 cm in the first year and between 93 and 131 cm in the second season. The lines headed in May, between 10th to 22nd with an average of May 15th. Fertility was calculated by dividing seeds to spikelet number in self- and open-pollinated spikes. Seed setting in self-fertility was lower than that of open-pollinated ears, but self-fertility in S-5 was higher than the same trait in S-6 generation (0.94 > 0.79 seeds per spikelet). Plant wax character was assessed and grouped as: glaucous phenotype, non-glaucous plant and non-glaucous spike. The non-glaucous inbred strain was studied over 3 years to show a stable expression of this trait. It was compared to its glaucous sister line, and to another glaucous inbred line, boring oblong shaped seeds. The waxless 389-9-2 was involved in crosses with four waxy lines in an open pollination scheme that produced hybrid seeds at a frequency of 36%. Analysis of F-1 hybrids showed overdominance inheritance on the six studied traits in 83.3% of the hybrid plants. The results outlined the inbred lines used in crosses as promising genotypes for rye breeding.