Abstract:
Nanotechnology is the fastest growing industry now-a-days which is having considerable impacts on society, economy, and also on environment. One of the most recent aspects in the domain of environment and nanotechnology is the potential assessment of nanoparticles interactions with plants. This study focused on interactive effect of phosphorus fertilizer levels and TiO2 nanoparticles method of application on growth of rice. Rice was exposed to TiO2 nanoparticles using three different methods i.e. via irrigation, soil application and foliar spray. For each treatment, there were four phosphorus levels (P1 = 0 mg kg-1, P2 = 10 mg kg-1, P3 = 20 mg kg-1, P4 = 40 mg kg-1), whereas recommended N (70 mg kg-1) and K (32.5 mg kg-1) were added. The first phase and analysis, focused on plants’ growth variations under these treatments. The purpose of second phase was to assess plant uptake of phosphorus and rice grain protein content. The results revealed significant (p < 0.05) combined effects of TiO2 nanoparticles method of application and phosphorus fertilizer level on root dry weight and grain protein content. The highest shoot length (63.4 cm), number of tillers (7 n plant-1), root dry weight (6.2 g plant-1), shoot dry weight (7.52 g plant-1), shoot phosphorus (1140 mg kg-1) and rice grain protein content (23.8%) were recorded under the application of TiO2 nanoparticles through irrigation method in combination with 40 mg P kg-1, although this method of TiO2 nanoparticles application performed equally good at half dose of 20 mg P kg-1. The positive effects of TiO2 nanoparticles can be attributed to their ability to penetrate through the root surfaces, improving root water and nutrient acquisition, therefore enhance the fertilizer use efficiency. TiO2 nanoparticles might have exerted catalytic role to trigger metabolic activities for plant growth. Further detailed studies are needed to understand the mechanisms involved in improved phosphorus uptake and plant growth.
