Marker-assisted introgression of resistance to fusarium wilt race 2 in Pusa 256, an elite cultivar of desi chickpea.

Fusarium wilt caused by F. oxysporum f. sp. ciceris causes extensive damage to chickpea (Cicer arietinum L.) in many parts of the world. In the central part of India, pathogen race 2 (Foc 2) causes severe yield losses. We initiated molecular marker-assisted backcrossing (MABC) using desi cultivar, Vijay, as a donor to introgress resistance to this race (Foc2) in Pusa 256, another elite desi cultivar of chickpea. To confirm introgression of resistance for this race, foreground selection was undertaken using two SSR markers (TA 37 and TA110), with background selection to observe the recovery of recurrent parent genome using 45 SSRs accommodated in 8 multiplexes. F plants were confirmed with molecular markers and backcrossed with Pusa 256, followed by cycles of foreground and background selection at each stage to generate 161 plants in BCF during the period 2009-2013. Similarly, 46 BCF plants were also generated in another set during the same period. On the basis of foreground selection, 46 plants were found homozygotes in BCF. Among them, 17 plants recorded >91% background recovery with the highest recovery percentage of 96%. In BCF also, 14 hybrid plants recorded a background recovery of >85% with the highest background recovery percentage of >94%. The identified plants were selfed to obtain 1341 BCF and 2198 BCF seeds which were screened phenotypically for resistance to fusarium wilt (race 2) besides doing marker analysis. Finally, 17 BCF and 11 BCF lines were obtained which led to identification of 5 highly resistant lines of Pusa 256 with Foc 2 gene introgressed in them. Development of these lines will help in horizontal as well as vertical expansion of chickpea in central part of India.