Absorption of Carbon-13 Labelled Fullerene (C) on Rice Seedlings and Effect of Phytohormones on Growth.

This study explores the effects of nanomaterials in rice seedlings using carbon 13 (C)-labelled fullerene (C). The experiment consisted of three groups, one CK and two nano particle groups with C: 100 mg L and 20 mg L. Mass spectrometry indicated higher C abundances in the nano particle groups compared with the CK. The C abundances of the 20 mg L group, 100 mg L group and CK were 1.0718%, 1.0715% and 1.0704%, respectively. We analyzed phytohormone concentrations in the rice at harvest time. Decreases in the concentrations of dihydrozeatin riboside (23% and 18% for the 20 mg L and 100 mg L group, respectively), zeatin riboside (23% and 18%, respectively), abscisic acid (11.1% and 12.7%, respectively), brassinolide (12.9% and 13.1%, respectively) and gibberellic acid 4 (12.9% and 13.1%, respectively) were observed compared with the CK. The gibberellic acid 3 concentrations in the 20 mg L and 100 mg L group increased by 12% and 7% compared with the CK, respectively. The methyl jasmonate concentration in the 100 mg L group increased by 19.4% compared with the CK. The concentration of indole-3-acetic acid in the 100 mg L group decreased by 13.5% compared with the CK. There was no change on isopentenyl adenosine concentration. This study indicates that C can be absorbed by rice and its effect on the growth of rice via phytohormones, including ABA, IAA, IPA, BR, GA₃, GA₄, DHZR, ZR and JA-ME. The results showed that, under the treatments of C NMs, the contents of some phytohormone in rice were decreased in comparison with CK.