Abstract: Black phosphorus nanosheets (BPNSs) as a potential nano fertilizer would bring new opportunities for agriculture development. We conducted a co-cultivation experiment of BPNSs and soybean to verify the accumulation process of BPNSs and its degradation product phosphate in plants, and to explore the influence of BPNSs on soybean growth traits. The results showed that BPNSs significantly increased phosphorus content of soybean plants, especially in roots. Under phosphorus-deficient Hoagland culture conditions, root phosphorus content of the BPNSs treatment group increased by 45.8%, and the aboveground phosphorus content increased by 8%. Leaf chlorosis and phosphorus-deficient symptoms of soybean was significantly delayed, which facilitated the growth rate of aboveground and belowground parts and help them return to normal. Moreover, the observation results of transmission electron microscopy (TEM) indicated that a large number of BPNSs were enriched in roots, especially in the root pith, which explains why root phosphorus content in the BPNSs treatment was much higher than that of the control group. This study provides basic data for the application of BPNSs in nanotechnology-based agriculture.

Key words: black phosphorus nanosheet, phosphorus effect, phosphorus deficiency, soybean, growth trait