Effect of Multi-walled Carbon Nanotubes, Urea, and Peat Moss on Growth and Yield of Bean Plants Cultivated in Sandy Soil

This study was designed to investigate the potential of using carbon nanotubes (CNTs) either alone or loaded with urea and peat moss to reclaim sandy soil. A pot study (over 3 seasons) was designed in which bean seeds were planted in sandy soil either alone or amended with different concentrations of urea, peat moss, and multi-walled carbon nanotubes. In general, soil conditioners amended to the sandy soil caused a significant increase in all of the growth and yield attributes of the Phaseolus vulgaris plants over the 3 consecutive growth and developmental phases under study. The foliar application of carbon nanotubes to bean plants grown in sandy soil for all the duration of the experiment reduced ion leakage from the differently treated plants below the control levels. Furthermore, the addition of CNTs alone or in combination with urea and/or peat moss to sandy soil induced significant increases in all enzymatic antioxidants determined in the bean plants. It is worth highlighting that foliar application of CNTs alone or mixed with urea and/or peat moss reduced kidney bean crop life duration by 20.00% when compared to the normal life span of the relevant crop. On the other hand, the soil integration treatment used on kidney bean plants shortened their lifespan by 16.91% as compared with control plants. There may be some discrepancy between the changes in enzymatic antioxidants seen in vegetative bean plants and the corresponding changes in growth and yield owing to metabolic alterations caused by varying CNT concentrations or soil conditioners. Aside from that, the data clearly showed that CNTs (foliar spray) + urea + peat moss was superior to CNTs + urea + peat moss (soil incorporation). This is the best strategy for restoring sandy soil. These new and original discoveries may also be a new nanotechnology method for recovering sandy soil for agricultural development.