Conclusion
In this study, we obtained tetraploid and octoploid J. curcas by treating the shoot tips of seedlings with colchicine. Compared with diploid J. curcas plants, the sizes of stomata, leaves, male and female flowers, pollen, fruits and seeds of tetraploid plants became larger, but stomatal density, the stomatal conductance, single seed weight and oil content decreased. The octoploid plants were sterile, with no flower buds on three-year-old plants. Compared with those of diploid plants, the stomata became larger, and leaves became thicker in octoploid plants, but the plant height, leaf size, stomatal density, the net photosynthetic rate, and stomatal conductance decreased.