Effects of CuSO4 and Uniconazole on Mature Embryo Culture in Japonica Rice

In order to establish the system of high frequency plant regeneration for japonica rice mature embryos, the effects of different concentrations of CuSO4 and uniconazole on in vitro culture of mature embryos were studied using three rice cultivars of Kongyu 131, Longjing 24, and Dongnong 425 as test materials. The results showed that callus induction and differentiation of japonica rice mature embryos were apparently improved on the medium with 10–15 μmol • L−1 CuSO4 and 0.50–1.00 mg • L−1 uniconazole. Induction and differentiation rates of different genotype rice mature embryos displayed different sensitivities to CuSO4 and uniconazole. For the callus induction frequency of three varieties, the optimal concentration of CuSO4 was 15.0 mol • L−1. When the concentration of CuSO4 was 15 μmol • L−1, the plantlet differentiation rates of Kongyu 131 and Dongnong 425 got to the highest, while the concentration of CuSO4 was 10 μmol • L−1 for Longjing 24. For the callus induction and plantlet differentiation rates of Kongyu 131 and Dongnong 425, the ideal concentration of uniconazole was 0.50 mg • L−1 and for Longjing 24 was 1.00 mg • L−1.