NP   Lettuce Radish Cucumber Types EC50 (mg/L) GI affected by 1000 mg/L NP EC50 (mg/L) GI affected by 1000 mg/L NP EC50 (mg/L) GI affected by 1000 mg/L NP CuO 12.9 -100%* 397.6 -100%* 175.4 -100%* NiO 27.9 -100%* 400.7 -100%* 228.2 -100%* Fe2O3 > 5000 -55.0%* > 5000 -38.4% 1682 -68.4%* TiO2 > 5000 -36.2% > 5000  -47.6%* > 5000 -10.2% Co3O4 > 5000 -43.6% > 5000 +13.7% > 5000 -20.7% GI – Germination Index; ‘+’ - enhancement, ‘-’ – inhibition, ‘*’ – significant difference

Table 1: Effects of NPs on seeds activities.