Study of in vitro selection and plant regeneration of Indica rice tolerant to iron

Iron tolerant callus lines of Indica rice Vars. Khandagiri and Jagannath has been achieved on Murashige and Skoog (MS) medium supplemented with 1.0 mg/l Kinetin, 3.0 mg/l 2,4-D, 12 mM Fe. Somatic embryos derived from both tolerant non-tolerant calluses are germinated on MS medium supplemented with 1.0 mg/l 6-benzylaminopurine (BA), 0.25 mg/l 1-napthalen-eacetic acid (NAA) and 12 mM Fe within four weeks of subculture. The growth parameters like fresh and dry weight of callus, growth tolerance index, enzyme activity (Catalase and Peroxidase) and biochemical markers were used as indicators of iron tolerance. Measurements as early as two weeks after the beginning of the treatments did not yield consistent results. However, the growth tolerance index in the four weeks after the beginning of treatments yielded significant differences among non-tolerant and tolerant calluses. The enzyme activity is enhanced in the tolerant calluses than non-tolerant one. The in vitro raised plantlets derived from tolerant callus lines are grown in vitro in the presence of BA, NAA and 12 mM iron. The tolerant plantlets are established in the pots with iron-rich soil. This study will help to develop iron tolerant rice plants for breeding program.

Khandagiri and Jagannath callus lines showed tolerance to Fe and the plants are also growing normally in the iron rich soil.

The enzyme activities were significantly higher in tolerant callus lines and pigment content was also more in tolerant callus compare with non-tolerant calluses.