The presented field experiment on rice (Oryza sativa L.) commenced in the summer of 2020 at the Rice Research Station in Al-Mishkhab, Iraq, aiming to estimate the genetic parameters of rice cultivars using bio-, organic, and mineral fertilizers. The experiment layout had a randomized complete block design (RCBD) with a split-plot arrangement and three replications. The main plots included fertilizer combinations, i.e., full dose of mineral fertilizer (T0), full dose of biological fertilizer (T1), full dose of organic fertilizer (T2), half of the mineral and biofertilizer (T3), half of the organic and biofertilizer (T4), and half of the organic and mineral fertilizer (T5). The subplots comprised six rice cultivars, i.e., Yasamin, Dijlah, Mishkhab-2, Brnamge-4, Amber-33, and Ghadeer. The results revealed, on average, the rice cultivar Amber-33 had the tallest plant height (107.32 cm) and minimum days to 50% flowering (103.73 days), and cultivar Dijlah had the highest average for panicle length, 1000-grain weight, and biological yield (28.12 cm, 23.05 g, and 12.29 t ha^-1, respectively). Cultivar Yasamin showed the maximum grain yield (4.50 t ha^-1) compared with other cultivars. For fertilizer treatments, half of the organic and mineral fertilizer (T5) had the utmost average of grain yield (4.05 t ha^-1), and half of the mineral and biofertilizer (T3) had the maximum plant height, panicle length, and biological yield (90.24 cm, 25.13 cm, and 13.58 t ha^-1, respectively).

Keywords: Rice (O. sativa L.) cultivars, biological fertilizers, mineral fertilizers, organic fertilizers, , growth and yield traits

Key findings: Rice (O. sativa L.) cultivars and fertilizer combinations revealed significant differences for all the traits. Cultivar Yasamin showed the highest average grain yield (4.50 t ha^-1). The solutions with half of the organic and mineral fertilizer (T5) and half of the mineral and biofertilizer (T3) excelled in most of the characteristics under study.