The effects of nano TiO_2 and Nano aluminium on the growth and some physiological parameters of the wheat (Triticum aestivum)

Nanoparticles are atomic or molecular particles with at least 1–100 nanometer diameters. they have entered vastly into the world of agriculture and biology; this is because of their special effect and their unique features. their unknown impact on living things and the ecosystems has caused a lot of concern. this research was done in order to study the effects of nano-tio_2 and nano aluminium on wheat (triticum aestivum). both nano titanium dioxide and nano aluminium were used in four concentrations {(0, 100, 1000, 2000 mgl^-1) and (0, 500, 100, 1000, 2000 mgl^-1) respectively}. the experiment was done as factorial in a completely randomized design in 3 replications. the seeds were sterilized and transferred into pots containing sand. when the plants reached four leaves stages, the nanoparticles were sprayed on plants two times in a week internal. the results revealed that nano aluminium decreased the length of root and shoot and the content of chlorophyll; however, it increased the content of proline and malondialdehyde in shoot and root. the treatment of plants in different levels of nano aluminium with nano titanium dioxide especially in 100 mgl^-1 concentration increased the length of both the root and shoot. nano titanium dioxide in 1000 and 2000 mgl^-1 increased the mda and proline content. generally the application of nano titanium dioxide in low concentration can moderate the damage effects of nano aluminium in the range of 100 mgl^-1.