Screening of the effects of Zinc oxide based nanofertilizers on the germination of Lathyrus sativa L. seeds

Zinc based nanofertilizers may be useful tools in improving crop culture, especially in Zinc deficient soil. The present study aims to investigate the role of nanosized zinc oxide particles (ZnO NPs, diameter<100 nm) in modulating seed germination, embryo nutrition and growth of grass pea (Lathyrus sativus L.). Our data revealed ameliorating or inhibiting effects depending of the concentration of ZnO NPs administrated. At metabolic level, the growing embryonic axes seem to cope with induced oxidative stress, by enhancing hydrogen peroxide scavenging capacity. We revealed interesting regulatory mechanisms evolved within the embryonic cells to limit the oxidative damages induced by ZnO NPs and Zinc sulfate when applied at low concentrations (0.01 mg mL-1, 0.1 mg mL-1). Nonetheless, at high concentrations (1 mg mL-1, 10 mg mL-1), ZnO NPs led to drastic perturbations in the metabolism, which resulted in the inhibition of root and seedling growth. Our work may bring novel insight into the mechanistic understanding of the physiological role of the nanosized ZnO in enhancing the efficacy of fertilization. We also assess the critical role of applied concentration of nano-fertilisers to avoid toxicity to plants. Such phytotoxicity is not only affecting crops yield, but also may alter the biological properties and the nutritive quality of plant-derived food products, which may endanger or risk human health