Brassica carinata (BBCC, 2n=34) has still to emerge as a major oilseed crop owing to poor agronomic attributes like long stature, long maturity duration and low seed yield. The restricted amount of genetic variability available in natural B. carinata necessitates utilization of new sources of variability for broadening its genetic base. Interspecific hybridization followed by selection in selfed and back cross progenies was employed to generate useful variability into B. carinata cv ˈPC5ˈ from elite lines of Brassica napus (AACC, 2n=38) and Brassica juncea (AABB, 2n=36). The morphological evaluation of 24 stable introgressed progenies revealed wide range of variability for key economic traits. The progenies with mean maturity duration of 161 ± 2.1 days, short stature of 139.5 ± 6.5 cm and seed yield per plant of 18.6 ± 2.0 g in comparison to the corresponding figures of 168 ± 4.6 days, 230.6 ± 12.7 cm and 12.0 ± 2.4 g in ˈPC5ˈ (recurrent parent) were recovered. Diversity analysis at morphological level revealed that 22 out of 24 stable introgressed progenies were grouped with B. carinata ˈPC5ˈ at average taxonomic distance of 1.19. The diversity at molecular level using 25 polymorphic and reproducible RAPD primers revealed that 19 out of 21 introgressed progenies grouped with B. carinata ˈPC5ˈ at a similarity coefficient of 0.68. The clusters in general represent a wide range of genetic diversity in the back cross lines of B. carinata as a result of introgression of genes from elite lines of B. napus and B. juncea parents.

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Sof unknown function and with an Arabidopsis RNA methyltransferase. This seems to indicate a post-transcriptional mechanism of control for somatic embryogenesis induction. To evaluate the role of this protein during the embryogenic process we decided to test if somatic embryogenesis induction could be affected in knockedout lines of Arabidopsis for the identified cDNA. Knocked-out lines were obtained from NASC and were evaluated for their ability to undergo somatic embryogenesis in comparison with wild-type seeds (Columbia). For somatic embryogenesis induction the immature seeds were cultured on Gamborg medium, supplemented with 2,4-dichlorophenoxyacetic acid 4.5 M, for 21 days, under a photoperiod of 16 hours light/8 hours dark, at a temperature of 25 • C. The results showed that the levels of somatic embryogenesis induction were higher in the knocked-out lines (41% induction) than in the control (5%). Somatic embryos appeared after 15 days of culture and developed in green embryos possessing two or fused cotyledon-like structures identical to those described in the literature during somatic embryogenesis induction in Arabidopsis. The cotyledon-like structures did not possess trichomes thus confirming its embryogenic rather than organogenic origin. Histological studies are being performed to better characterize the development of these embryogenic structures and attempts to convert them into plantlets are also in course. The results so far obtained seem to prove that the protein consistently expressed in non-embryogenic calluses of tamarillo is an inhibitor of somatic embryogenesis induction. How this protein impairs the expression of the embryogenic potential is not known and needs further analysis. Attempts are being conducted to verify if NEP gene silencing in tamarillo also promotes somatic embryogenesis induction.