Variability of Root Anatomical Traits in Rice Germplasm

Root traits influence the amount of water and nutrient absorption, and are important for maintaining crop yield under drought conditions. The objectives of this research were tocharacterize variability of root traits among rice genotypes. Plants were grown in 150 cm columns for 45 days in a greenhouse under optimal growth conditions. Root diameter, Cortex diameter, Stele diameter, late meta-xylem diameterand number of xylem were determined for 268 genotypes of the rice germplasm, Significant genetic variability was observed for root anatomical traits among rice genotypes in Indica panel. Five quantitative characters i.e. root cross section diameter, root cortex diameter, stele diameter, late meta-xylem diameter and late meta xylem number were measured. The largest variation was observed for late meta-xylem number with Coefficient of Variation (CV) of 11.56% followed by stele diameter, late meta-xylem diameter, root cortex diameter and root cross section diameter. Ratio of stele diameter to root diameter has shown the least variation with the CV of 6.51%. The trait such as stele diameter, late meta-xylem diameter, late metaxylem number and ratio of stele diameter to root diameter has recorded as leptokurtic. All the traits registered as positively skewed. The genetic variability identified in this research for root traits can be exploited toimprove drought tolerance and/or resource capture in rice.