REVIEW OF THE METHODS FOR BREEDING OF SESAME VARIETIES (SESAMUM INDICUM L.) IN BULGARIA

An overview of Bulgarian methods for breeding of sesame varieties suitable for mechanized harvesting is presented. Thirty-year scientific work is conditionally divided into four periods. In the first period (1987 - 2003) has been received genotypes enable breeders to improve the quality of their products. In the second period (2004 - 2008) has been created a method for measuring the strength for breaking up of non-shattering sesame capsules. It has been created the first Bulgarian sesame variety with closed capsules at maturation, which is intended to mechanize harvesting. In the third period (2006 - 2011) has been developed a new method for evaluating the possibility for mechanized harvesting of breeding materials. A placenta which is attached to seeds up to full maturity has been discovered in the new breeding materials. All of them are susceptible for inertial threshing which does not lead to mechanical damaging of seeds. In the fourth period (2011 - 2017) has been developed a new objective method for evaluating the suitability of the hybrids for mechanized harvesting. This period continues with selection of varieties that retains the seeds in the capsules while matured sesame plants are on the field and are subjected to tilting by the wind.