1536 AJCS 12(09):1536-1542 (2018) ISSN:1835-2707 doi: 10.21475/ajcs.18.12.09.PNE1382 Effects of Boron (B) doses and forms on boron use efficiency of wheat Fernando Shintate Galindo 1* , Marcelo Carvalho Minhoto Teixeira Filho 1 , Salatiér Buzetti 1 , Willian Lima Rodrigues 1 , Eduardo Henrique Marcandalli Boleta 1 , José Mateus Kondo Santini 2 , Maikon Richer de Azambuja Pereira 1 1 Department of Plant Health, Rural Engineering, and Soils, Faculdade de Engenharia de Ilha Solteira, Universidade Estadual Paulista “Júlio de Mesquita Filho”, Ilha Solteira, Sao Paulo State, Zip Code 15385-000, Brazil 2 Higher Education Institute of Rio Verde, College Objetivo, Rio Verde, State of Goiás, Brazil * Corresponding author: fs.galindo@yahoo.com.br Abstract Boron is one of the most limiting micronutrients in the grain production system in Brazil, mainly due to its complex dynamics in the soil-plant system. In this way, the objective of this study was to evaluate the efficiency of application forms and doses of boron with emphasis on wheat grain yield. The experiment was conducted in no-tillage system in an Oxisol with clay texture in Selvíria, MS. The experimental design was a randomized block design with four replicates arranged in a 4 x 3 factorial scheme, using four doses of boron (0, 1, 2 and 4 kg ha -1 ) with boric acid source (B = 17%); and three apllication forms: (A1) in desiccation of the predecessor straw, along with herbicide; (A2) at the time of sowing, in soil along with the formulated fertilization seeding and (A3) foliar application along with the syrup of the herbicide (with the application of post emergent herbicide). The increase in boron doses reduced the recovery of apparent boron (RAB), boron uptake efficiency (BUpE) and agronomic efficiency (AE), but the application of 2 kg ha -1 provided the highest boron utilization efficiency (BUtE) and wheat grain yield. We recommend application of 2 kg ha -1 of B in the soil at sowing to obtain approximately 4311 kg ha -1 of wheat. Keywords: Efficiency of borated fertilization, Borated fertilization, Boron time application, Boron uptake, Triticum aestivum. Abbreviations: RAB_Recovery of applied boron; PE_physiological efficiency; AGREC_agrophysiological efficiency; BUtE_boron utilization efficiency; BUpE_boron uptake efficiency; AE_agronomic efficiency; BHI_boron harvest index; a.i._active ingredient; O.M._organic matter Introduction Wheat (Triticum aestivum L.) is an annual cycle plant, considered among the cool season cereal, one that has greater economic importance with large grain yield capacity (Teixeira Filho et al., 2010; 2012; 2014; Marini et al., 2011; Theago et al., 2014). This cereal occupies over 17% of cultivable land in the world and represents approximately 30% of world grain production. In the periods from 2012 to 2016, the annual average area of wheat cultivation worldwide was approximately 220 million hectares, reaching 734 million tons in the 2015/2016 harvest (USDA, 2016). Fertilization is recognized as one of the factors that favors the productivity and sustainability of the activity (Araújo, 2011; Galindo et al., 2016; 2017a; 2017b). Among the nutrients that most affect productivity, boron (B) is the most limiting micronutrient for crops, especially in the tropical soils, which are generally low in available B and organic matter, which is a major source of this nutrient to plants, affecting inadequacy in plant nutrition (Souza et al., 2011). Boron is an essential element to plant growth, participating in several processes, such as sugar transport, lignification, cell wall structure, carbohydrate metabolism, RNA metabolism, respiration, indole acetic acid (IAA) metabolism, phenolic metabolism, ascorbate metabolism, besides it has function in cell wall synthesis and plasma membrane integrity (Calonego et al., 2010; Foloni et al., 2016). According to Metwally et al. (2017), B influences the germination of the pollen grain and pollen tube growth, increases flower glue and granulation, causes less male sterility and less grain puffiness. In addition to the better fertilization of flowers and grain formation, B interferes with the retention of newly formed spikes, besides acting on meristem growth, cell differentiation, maturation, cell division and plant growth (Tahir et al., 2009; Muhmood et al., 2014; Galindo et al., 2018). As a result of its low mobility within the phloem, there is a need for a constant availability or supply of this nutrient during the vegetative phase of the plants (Calonego et al., 2010; Mantovani et al., 2013). Therefore, conduction of further studies on the ideal boron management and boron fertilization is of highly importance. However, there are few studies on B fertilization in wheat cultivation focusing on the best application method associated with the appropriate dose of this nutrient, aiming to improve the efficiency of boron fertilization. The hypothesis of this study is based on the complex dynamics of boron in the soil-plant system, where it would