International Journal of New Technology and Research (IJNTR) ISSN:2454-4116, Volume-1, Issue-7, November 2015 Pages 48-50 48 www.ijntr.org Abstract- This work focuses on the study of the effect of lanthanum application on Rangpur lime (Citrus limonia Osbeck). The experiment was carried out in a greenhouse. Four different doses of lanthanum chloride heptahydrate (50 mg, 100 mg, 200 mg, 400 mg) per citrus plants were applied ninety-eight days after the sowing. The plants were collected three weeks following the application of the lanthanum chloride the plants. The optimal dose was 50 mg. The results showed that the citrus plant physiology changed with the application of lanthanum, i.e., depending on the dose, there is a beneficial or a harmful effect on the growth. Index Terms— citrus, lanthanum, rare earth elements, toxicology. I. INTRODUCTION Rare earth elements (REE) are a cohesive group [1] of 17 chemical elements. It includes the lanthanide series, scandium (Sc) and yttrium (Y). They are usually classified into two categories: light rare earth elements (LREE, from lanthanum to europium) and heavy rare earth elements (HREE, from terbium to lutetium, including yttrium) [2]. The definition of LREE and HREE is based on the electron configuration of each rare earth element. However, scandium properties are not similar enough to classify it as either a LREE or HREE [3]. REE can not be considered rare [4]. For example, cerium (Ce) concentration in nature is similar to the concentration of copper (Cu) and zinc (Zn) [5]. The concentration of REE in soils depends on the composition of source rocks, the weathering conditions, among other factors, but in general the LREE predominate over the HREE ones [5]. REE are present in all plants, but they are not considered essential or toxic [6]. They can be uptake through leaves [7]. China was in fact the first country in the world to use commercial REE-fertilizers applied to crops in the form of foliar sprays, seed treatments or as additions to solid or liquid Christian Turra, Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, Piracicaba, Brazil, Elisabete A. De Nadai Fernandes, Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, Piracicaba, Brazil, Márcio Arruda Bacchi, Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, Piracicaba, Brazil, Gabriel Adrián Sarriés, Escola Superior de Agricultura “Luiz de Queiroz”, Universidade de São Paulo, Piracicaba, SP, Brazil, Fernando Barbosa Júnior, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil, André Luís Teixeira Creste, Cia. Agrícola São José, Rio Claro, SP, Brazil. Andrés Enrique Lai Reyes, Escola Superior de Agricultura “Luiz de Queiroz”, Universidade de São Paulo, Piracicaba, SP, Brazil, root fertilizer formulations [8]. More than 100 crops responded to the application of REE with yield increases ranging from 5% to 10%. Use of adequate REE can promote the germination of seeds and roots development, increase plant biomass, and improve the quality of fruiting bodies [9]. Studies have reported effects of REE to plants, both beneficial [5, 8] and undesirable [10, 11, 12], and a possible relationship of REE with the physiology of plants [13, 14]. Normal concentration of lanthanum (La) in leaves is in the range 0.15 – 0.25 mg kg -1 [15]. However, some experiments [16] found La concentrations in citrus leaves similar to those found in the soil with soil-to-plant transfer factors of 0.65 to 1.05. There are some works with La application in different cultures – tobacco [17]; corn and mungbean [18]; wheat [19]; corn, green gram and black gram seeds [20]. These effects of La application on plants depending on the dose, the type of plant and other conditions. Agricultural supplies can have REE in your composition, mainly in fertilizers rich in P 2 O 5 [21, 22] and citrus plants can accumulate these elements [16]. The Brazilian citriculture demands significant amounts of agricultural supplies to maintain satisfactory production. REE are present in different parts of citrus plants. These elements were also determined in sweet orange fruit (seed, pulp, juice and peel) in Brazil [16]. However, there is no information about uptake by citrus plants and the possible effects of these elements in this culture. This work focuses on study of the lanthanum effect in the citrus plant. The lanthanum chloride heptahydrate (LaCl 3. 7h 2 O) was used as the REE source to experiment due to the high solubility in water and high lanthanum concentration (minimum 99.9%). II. MATERIAL AND METHODS Two seeds of Rangpur lime (Citrus limonia Osbeck) were sowing in each of 456 polypropylene tubes (50 cm -3 ). The substrates used in the sowing were Plantimax (composted pine bark, expanded vermiculite, expanded perlite, peat, concealer and chemical fertilizer) and Vida Verde (composted pine bark, charcoal, phenolic foam and concealer). It was added Osmocote fertilizer (NPK 19 10 6) in the final substrate (2 g of Osmocote per kg of total substrate). The mixture was homogenized before sowing. It was selected one plant per tube, thirty days after sowing. Ninety-eight days after sowing were applied different treatments in Rangur lime plants. Three weeks after treatments application, the plants were collected. Then citrus Effects of Lanthanum on Citrus Plant Christian Turra, Elisabete A. De Nadai Fernandes, Márcio Arruda Bacchi, Gabriel Adrián Sarriés, Fernando Barbosa Júnior, André Luís Teixeira Creste, Andrés Enrique Lai Reyes.