shankar goudaSHIVALEELA S. KUKANUR2020-07-092020-07-092019-01-30200http://krishikosh.egranth.ac.in/handle/1/5810148895Sunflower (Helianthus annuus L.) is a cross pollinated crop originated from North America and is the second largest hybrid crop next to maize and fifth largest oilseed crop after soybean, rapeseed, cottonseed and groundnut in the world. It belongs to the family Asteraceae and genus Helianthus with the basic chromosome number x =17 consisting of diploids (2n=2x=34), tetraploids (2n=4x=68) and hexaploids (2n=6x=102) with 51 species and 19 subspecies with 14 annual and 37 perennial species. This abundance and diversity of species offers numerous and rewarding possibilities to create variability in sunflower. In the present investigation interspecific hybridization has been done between cultivated annual diploid H. annuus L. CMS 38B and wild annual diploid H. argophyllus Torr. & A. Gray HEL 153/83 and characterized the interspecific crosses at morphological, cytological and molecular level and associated the SSR markers to yield component traits using BC1F1 and BC1F2 population derived from the cross. The two parents were found diverse for all the traits studied. At morphological level, the interspecific hybrid plants were observed with characters approximating the characters of either parent, individuals with variation and also similar to either of the parents. This large genetic variability provides the basic necessary for successful plant breeding. At cytological level, meiosis was normal in both the parents but in interspecific cross some variability was observed with the percentage of univalent (4.78%), trivalents (1.12%), quadrivalents (7.27%), chromosomal bridges (6%) and laggards (5%). The occurrence of meiotic irregularities in the cross indicates that H. annuus and H. argophyllus differ in genome constitution. At molecular level the true F1s were confirmed by polymorphic SSR markers. Marker trait association analysis provided a total of 14 SSR markers significantly associated with at least one of the eight yield component traits. These markers may be further validated for marker assisted breeding programme. Key words: Interspecific hybridization, Meiosis, SSR, Marker trait association and Sunflower.ennullThesis