Role of elevated phosphorus on wheat plant under different split-root systems

Abstract

Phosphorus (P) is a key nutrient for plant growth and development. It is involved in cellular energy transfer, respiration and photosynthesis. Nutritional requirements of plants vary widely mostly under different ecological conditions. Most of the plants have to survive under adverse to the most severe conditions as they are genetically adapted to their habitats and even some varieties of the same species differ very much in absorption translocations, accumulation and nutrient use. The P is taken up from the soil solution by plant roots as orthophosphates ions, principally as mono-orthophosphates, H2PO4- ions in acidic soil solution while in alkaline soil solutions the principal ions that adsorbed/absorbed are monovalent orthophosphate, H2PO4- ions and divalent orthophosphate, HPO42- ions. In my several experiments, I have used two hypes of soils- one acidic soil having initial soil pH 5.2 in water and the other alkaline soil having initial soil pH 7.9 in water. Two recently BARI released wheat varieties namely BARI GOM 25 and BARI GOM 26 were used throughout the investigations. The KH2PO4 was used as a source of P. The experiments were carried out to examine different parameters such as the roles and effects of different P levels and application methods with three triplications in improving root and shoot developments of wheat plants (in split-root systems), plant growth and development by wheat seedlings, phosphorus use efficiency (PUE) by wheat plants that grown in both acidic and alkaline soils. Effects of added soluble P on the rate of absorption/adsorption of nutrients from the soil solutions and also the effect of P supply to the crop by the soil available P, P fertilizer management, soil and environmental conditions that influence P apply to availability and root-shoot ratio. The experimental results along with their comparison between BARI GOM 25 and BARI GOM 26 in acidic and alkaline soil which in turn show the betterment of wheat plant growth in acidic soil over alkaline soil in tabular and graphical forms. In acidic soil, results showed that the growth parameter plant biomass and P uptake increased 90%-91% with respect to the controlled treatment. Slightly better results but not highly significant, were found for BARI GOM 26 than those for BARI GOM 25. The findings clearly indicate that elevated P takes a significant part in wheat plant development and the added soluble P increases the absorption of nutrients from both acidic and alkaline solutions and the application of elevated P is efficient for both increasing shoot development and the root growths and the PUE with respect to plant utilization. Results also showed that alkaline soil are somewhat below than therefor acid soil. Moreover, the elevated P concentrations in the shoots of the wheat plants probably provided more P for shoot unloading of P and for P assimilation in the controlled roots, resulting in increased P concentrations in the roots of the wheat plants that means, the translocation of P in the roots in acidic and alkaline soils and there is no doubt that P plays a significant role in the P dynamics and P translocation within the wheat plants in split root systems (in both acidic and alkaline soils). The overall experimental results suggested that the acid soil is more suitable than alkaline soil for BARI GOM 25 and BARI GOM 26 wheat (Triticum aestivum L) cultivation. The study concluded that the both wheat varieties can able to utilize P efficiently in both acidic and alkaline soils with the overcoming of P fixation in both soils.