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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. [ABSTRACT FROM AUTHOR]

The dry matter partitioning is the product of the flow of assimilates from the source organs (leaves and stems) along the transport route to the storage organs (grains). A 2-year field experiment was conducted at the agronomy research farm of the University of Agriculture Peshawar, Pakistan during 2015–2016 (Y1) to 2016–2017 (Y2) having semiarid climate. Four summer crops, pearl millet (Pennisetum typhoidum L.), sorghum (Sorghum bicolor L.) and mungbean (Vigna radiata L.) and pigeonpea (Cajanus cajan L.) and four winter crops, wheat (Triticum aestivum L.), barley (Hordeum vulgare L.), fababean (Vicia faba) and rapeseed (Brassica napus) were grown under two irrigation regimes (full vs. limited irrigation) with the pattern of growing each crop either alone as sole crop or in combination of two crops in each intercropping system under both winter and summer seasons. The result showed that under full irrigated condition (no water stress), all crops had higher crop growth rate (CGR), leaf dry weight (LDW), stem dry weight (SDW), and spike/head dry weight (S/H/PDW) at both anthesis and physiological maturity (PM) than limited irrigated condition (water stress). In winter crops, both wheat and barley grown as sole crop or intercropped with fababean produced maximum CGR, LDW, SDW, S/H/PDW than other intercrops. Among summer crops, sorghum intercropped either with pigeon pea or with mungbean produced maximum CGR, LDW, SDW, and S/H/PDW at both growth stages. Sole mungbean and pigeon pea or pigeon pea and mungbean intercropping had higher CGR, LDW, SDW, S/H/PDW than millet and sorghum intercropping. On the other hand, wheat and barley grown as sole crops or intercropped with fababean produced maximum CGR, LDW, SDW, and S/H/PDW than other intercrops. Fababean grown as sole crop or intercropped with wheat produced higher CGR, LDW, SDW, and S/H/PDW at PM than intercropped with barley or rapeseed. From the results it was concluded that cereal plus legume intercropping particularly wheat/fababean in winter and sorghum/pigeon pea or sorgum/mungbean in summer are the most productive intercropping systems under both low and high moisture regimes. [ABSTRACT FROM AUTHOR]