A major QTL identified for vernalization response in chickpea

Wild species can be utilized as potential source to transfer new genes/alleles into domesticated chickpea. Wild chickpea species induce early flowering when exposed to low temperatures (vernalization). Genetics of vernalization was studied in an interspecific F10 recombinant inbred line (RIL) population [ICC 4958 (Cicer arietinum) x PI 489777 (Cicer reticulatum)] for two consecutive years (2009-10 and 2010-11) under field conditions. After vernalization (at 4°C) for one month, the seedlings of RILs were transplanted in the field along with control treatment (without vernalization). Flowering time difference between vernalization and control treatments was considered as vernalization response. A linkage map available from the public sources for the above population has been used for QTL analysis. A major QTL contributing 55% of phenotypic variation for vernalization response trait was identified on linkage group (LG) 3 at LOD score of 29. The simple sequence repeat (SSR) markers TA64 and CaM1515 were flanking the QTL which spans a distance of 22 cM. Further, integration of six Bacterial Artificial Chromosome (BAC)-end sequence derived SSRs (CaM0717, CaM2086, CaM1760, CaM1364, CaM1122, and CaM0886) present in the major QTL region, on to physical map can eventually help in isolation of vernalization genes. Among 84 flowering related genes present in this region, Ca_06280 related to MADS box genes, was reported to play important role in vernalization in cereals. Understanding the genetic control of vernalization response in chickpea will greatly help in exploitation of wild Cicer species in chickpea improvement