Kuldeep SinghNguyen Le Van2017-06-202017-06-202012http://krishikosh.egranth.ac.in/handle/1/5810022095Rice (Oryza sativa L.) is staple food for more than a third of the world’s population, and we need to produce 30% more rice to meet the demand in next 25 years. Utilization of wild species for enhancing productivity is one of the several approaches proposed for meeting food requirements. In this study we evaluated a number of BC2F6 introgression lines (ILs) generated from the crosses between O. sativa cv PR114 X O. longistaminata acc IRGC 104301 and using DNA markers identified regions introgressed from the wild species. A set of 45 ILs and three checks were evaluated in a complete randomized block design with three replications for two years. Data were recorded on 11 agronomic traits. Several ILs showed significant increase or decrease over the recurrent parent in yield components like plant height (PH), days to flowering (DF), tiller number (TN), panicle length (PL), spikelet per panicle (SPP), spikelet fertility (SF), grain length (GL), grain width (GW), thousand grains weight (TGW) and plot yield (PY) compared to the recurrent parent PR114. Ten ILs showed significant increase in SPP during both the years over the recurrent parent and the increase ranged from 9.3 – 41.0 per cent. Likewise, five ILs showed significant increase in grain length ranging from 4.95 – 10.1 per cent, two ILs showed significant increase (16.0%) in TGW, and nine ILs showed significant increase (6.4-24.1%) in grain width. Parent polymorphism between PR114 and donor species O. longistaminta was done using a set of 366 SSR markers spanning all the 12 linkage groups and 92 polymorphic SSRs were used for characterizing the ILs. The alien segments introgressed in each of the ILs varied from 1.09% to 13.04%. Alleles which showed positive effect from O. longistaminata were observed in chromosomal regions associated with DF, PL, SPP, GL and GW traits. Alleles associated with negative effects were also observed for PH, TN, SF, PY and grain size traits. The ILs showing significant increase for one or more traits have been identified and these could be used for mapping QTL introgressed for these traits, using bi-parental crosses.ennullThesis