Int.J.Curr.Microbiol.App.Sci (2019) 8(9): 369-373 369 Original Research Article https://doi.org/10.20546/ijcmas.2019.809.044 Field Evaluation of Backcross Progenies of Improved Samba Mahsuri Possessing SCM2 Gene P. Jayamma 1, 2 , C.H. Anuradha 1 , P. Senguttuvel 2 , E. Punniakotti 2 , M.B.V.N. Kousik 2 , G. Harika 2 , K. Chaitra 2 , T. Ramesh 1 , D. Subramanyam 2 and R.M. Sundaram 2 * 1 Institute of Biotechnology, Professor Jayashankar Telangana State Agricultural University (PJTSAU), Rajendranagar, Hyderabad 500030, India 2 Indian Council of Agricultural Research (ICAR)-Indian Institute of Rice Research (IIRR), Rajendranagar, Hyderabad 500030, India *Corresponding author ABSTRACT Introduction Rapid population growth and global demand for rice consumption has been estimated to rise from the present level of 700 million tons (mt) to 852 mt in 2035. In the case of India, where ‘rice is life’ and where population is steadily increasing, we need to increase rice production from the present level of 103 mt to at least 136 mt by the year 2050 (http://www.icar-iirr.org/IIRR%20Vision% 202050.pdf). Such a robust increase in rice production can be realized either by extending rice cultivation to additional land or by increasing the productivity per unit area. Increasing rice yields on existing land remain the major challenge for increasing production. Therefore, improvement in the yield potential of rice has proven to be the major strategy to increase global rice production particularly International Journal of Current Microbiology and Applied Sciences ISSN: 2319-7706 Volume 8 Number 09 (2019) Journal homepage: http://www.ijcmas.com India ranks second in production of rice (Oryza sativa). The culm plays an important role in determining the lodging resistance and crop architecture of rice. The gene, STRONG CULM (SCM2) has been reported to be associated with strong culm. In the present study, BC 2 F 2 lines in the background of Improved Samba Mahsuri (ISM) derived by crossing Improved Samba Mahsuri (ISM) and a breeding line of Swarna possessing SCM2 were genotyped for presence of SCM2 with a newly designed gene specific marker (SCM2-8F/8R) and plants positive for the gene were then phenotyped and measured for Culm thickness with an average of three plants per each line of the BC 2 F 2 selected best lines along with the parents for culm thickness by measuring the Culm diameter with Vernier Calipers and by observing the Internode Culm cross sections under Microscope. All the backcross plants possessing the gene had significantly better culm thickness, and culm diameter as compared to Improved Samba Mahsuri indicating a perfect co- segregation of trait phenotype with marker genotype, validating the utility of the marker. The backcross plants of ISM possessing increased culm strength are being crossed with breeding lines of ISM possessing higher number of per panicle. Keywords Back cross introgression lines, Improved Samaba Mashuri, SCM2, Gene specific and allele specific marker, Codominant marker, Culm diameter, Millimeters and μm Accepted: 04 August 2019 Available Online: 10 September 2019 Article Info