Nitrogen fertilizer ameliorate the remedial capacity of industrial hemp (Cannabis sativa L.) grown in lead contaminated soil

Abstract

Industrial hemp (Cannabis sativa L.) is a fibrous plant with high biomass production, and can survive under heavy metal stress conditions. To determine the growth potential of industrial hemp on lead (Pb) contaminated soil, a pot experiment was conducted using two varieties Bamahuoma (BM) and Yunma-1 (Y1), under different levels of nitrogen (N) fertilizer viz., 0 (control), 0.1, 0.3, 0.5 and 0.7 g kg⁻¹. The soil was artificially spiked with Pb using PbCl. Lead uptake and its accumulation in different organs of both hemp varieties were analyzed. Increasing level of N fertilizer caused a significant increase in the plant growth and dry biomass production in both varieties, while Y1 showed more tolerance to Pb, than BM. Furthermore, N (%) was higher in the leaves and stems then in the roots. Contrastingly, Pb was highly accumulated in the roots then in the leaves and stems of both varieties under varying levels of N fertilizer in the soil. Lead uptake and its accumulation in different plant parts were increased with the increase in N fertilizer in the soil. Hence, these findings indicate that external N fertilization is a useful strategy to enhance dry biomass and Pb accumulation in industrial hemp.

Keywords:

• Cannabis sativa
• lead contaminated soil
• nitrogen fertilizer
• phytoremediation
• plant growth

Additional information

Funding

This research was supported by a grant from the National Natural Science Foundation of China (31501350, 31660351 and 31760403), Natural Science Foundation of Yunnan (2016FB068 and 2017FD060), and China Agriculture Research System (CARS-16-E15). The authors also extend their appreciation to the Researchers supporting project number (RSP-2020/193) and King Saud University, Riyadh, Saudi Arabia.