Abstract

                                TNAU Rice Hybrid CO 4 (TNRH 174) a derivative of the cross TNAU CMS 23 A/ CB 174 R, released during the year 2011 matures in 130-135. The hybrid recorded a mean productivity of 7327 Kg/ha with 14.5 and 11.3 per cent increase over CO (R) 49, the fine rice check variety and 27P11, the private hybrid respectively. It gave higher yield under SRI than normal method and showed better agronomic efficiency than the check variety CO(R)49. The hybrid produced medium slender white rice with the L/B ratio of 2.96, with high milling percentage (68.6%) and head rice recovery (62.5%). It has intermediate amylose content (24.01), soft gel consistency (65) and moderate gelatinization temperature indicating its superior cooking quality. Upon cooking, linear elongation ratio (1.7) and volume expansion (5.0) ratio were higher than 27 P 11 and CO(R) 49. This hybrid showed higher yield, better pest and disease resistance and good cooking quality in comparison to the checks CO (R) 49 and 27 P11 and hence was released as a new medium duration hybrid, TNAU Rice Hybrid CO 4 for cultivation during late samba / thaladi season throughout Tamil Nadu.

Key words : TNAU Rice hybrid CO4, (TNRH 174) medium duration, medium slender rice