@article{Brito_Büll_Beltrão_Rigon_Sofiatti_2014, title={Absorption and critical levels of phosphorus in castor bean shoots grown in different soil classes}, volume={35}, url={https://ojs.uel.br/revistas/uel/index.php/semagrarias/article/view/14789}, DOI={10.5433/1679-0359.2014v35n1p239}, abstractNote={<p class="Pa7">Soil that has a high degree of weathering, with more inorganic P bound to Fe and Al oxides, has less P availability to plants. Thus, the critical element of a plant refers to the level below which the growth rate and plant production decreases, demonstrating the need for supplementary fertilization. Accordingly, an experiment was conducted in a greenhouse at Embrapa Algodão with the objective of evaluating the response of castor plants to five doses of P in four types of soil with different adsorption characteristics and critical levels of foliar P. The experimental design was completely randomized in a 4 x 5 factorial design, four types of soil and 5 levels of P with four replications. For TCo, there was an increase in height growth, with dose of 229.6 mg dm-3 responsible for maximum plant height (74.3 cm). The largest diameter stem (17.58 mm) was observed in CXve with an application of 229.6 mg dm-3 of P; a decrease was seen when using higher doses. The increase in leaf area was smaller in RY (4724.8 cm2), where it was obtained with a dose of 280.2 mg dm-3. In general, critical levels of P in the plant shoots did not vary much between the soils. The critical level of P in castor bean shoot dry mass was higher (4.61 g kg-1) in TCo, this result being directly related to the low clay content of the soil.</p>}, number={1}, journal={Semina: Ciências Agrárias}, author={Brito, José Félix and Büll, Leonardo Theodoro and Beltrão, Napoleão Esberard and Rigon, João Paulo Gonsiorkiewicz and Sofiatti, Valdinei}, year={2014}, month={fev.}, pages={239–250} }