Exploration and Genepool Sampling of Landrace Diversity in Oryza from Chhotanagpur Region Chandel K. P. S., Chauhan J. S.1, Chauhan V. S.1, Sinha P. K.1 National Bureau of Plant Genetic Resources, New Delhi. 1 Central Rice Research Institute, Rainfed Research Station, Hazaribagh (Bihar). Abstract Rich genetic diversity in Oryza landraces occur in Indian gene centre. Chhotanagpur plateau and adjoining. Orissa State possesses amazing variability in its landrace forms. Several wild species also continue to perpetuate in this region. Exploration and germplasm collection work was undertaken in Chhotanagpur region of Bihar comprising districts of Ranchi, Gumla, Lohardaga, parts of Palamau and Girdih and adjoining Keonjhar and Sundargarh districts of Orissa. Ecologically diverse regions and farming systems, representing varying soil and edaphic factors were explored for the collection of primitive diversity. The population samples from each site/miero-niche were obtained randomly, sampling 80–100 panicles/accession. Detailed observations were recorded on 10 randomly drawn panicles/accession. Detailed data were collected on different accessions for panicle and grain characters. The range, mean and standard error of means were calculated. The genepool sampling and its analysis showed occurrence of considerable genetic variability. The differences were prominent for varying degree of adaptation to different soil conditions. More than 150 distinct landraces of Oryza sativa var. indica were captured. Amazing genetic variability is exhibited in their forms, differing widely in plant height, foliage colour, internode length, stem thickness, stiffness of straw, maturity, grain size cplour, aroma and glume colour etc. Several genetically unique forms and wild Oryza species were collected during the exploration trip. The analysis of diversity showed the efficiency of random genepool sampling. Top |