Phytoextraction of enriched phosphate soil by cucumber ( Cucumis sativus ) and sunflower ( Helianthus annuus )

Soil phosphorus (P) enrichment due to increased P fertilizer use in agriculture contributes to eutrophication and adverse environmental impacts. Thus, one of the biggest global concerns is to reduce enriched P from the soil. One appealing way to remove excessive of P in soil is through phytoextraction. Therefore, a study was conducted to evaluate cucumber ( Cucumis sativus ) and sunflower ( Helianthus annus ) for phytoextraction and the effectiveness of chemical amendments for soil P reduction. Crops were grown in a factorial design with five treatments, including control − 0P, applied recommended P for the crop, 0P + 6 g Ca/kg, 0P + 2.0 g Al/kg, and 0P + 0.6 g Fe/kg. Phosphorus accumulation was as high as 1.70% of dry weight for cucumber and 1.50% for sunflower. When cucumber and sunflower were grown in the control soil, the available P concentration was reduced by 11.04 and 7.50%, respectively. The available P was decreased after adding alum by 36.02 and 32.9% in soil used to grow cucumber and sunflowers, respectively with the yield reduction by 23.3 and 14.3%. Similarly, the yield reduction of two crops was 21.5 and 9.8% with application of FeCl 3 . The crop yields were not affected by the application of CaCO 3 . A greater reduction in resin P fraction in soils was observed in cucumber (93.12%) and sunflower (94.98%). The P can be removed from P-enriched soils by cucumber and sunflower crops at 2.20 and 1.13 g P/plant dry weight without affecting the yield. It can be concluded that even though both crops are worthy nominees for phytoextraction, the cucumber shows superior ability over the sunflower.