Sources of phosphorus associated inoculation with Pseudomonas fluorescens in development and maize yield Fontes de fósforo associadas à inocula o com Pseudomonas fluorescens no desenvolvimento e produtividade do milho

The increased use of fertilizers to raise phosphorus availability to plants has promoted a strong economic impact on agriculture. For the better efficiency of use of phosphate fertilizers, this study aimed to evaluate the effect of P sources linked to inoculation with Pseudomonas fluorescens via seeds, in the development and yield components of corn plants. The experiment was conducted in the field, in 6x2 factorial, in randomized block design with four replications. Were applied 120 kg ha-1 P in the soil through five sources: triple superphosphate (SFT), Gafsa rock phosphate, Itafos rock phosphate, SFT+Gafsa and SFT+Itafos, and a control treatment (no P). The seeds of the cultivar AG 8088 were subjected to inoculation or not with the Pseudomonas fluorescens strain 1008. The variables studied in the flowering were: plant height (AP), height of ear insertion (AIE), stem diameter (DC), leaf area AF), leaf dry mass (MSF), total dry weight (MST) and leaf P content (PF). At harvest, there was the assessment of yield components: number of kernels per ear (NG), weight of 100 grains (M100), P content in grain (PG), yield (PROD), harvest index (IC) and relative agronomic effectiveness (EAR). The inoculation with P. fluorescens to seeds increased the AIE and AP when used SFT. At control the rhizobacteria inoculation resulted in 87% of EAR. The applications of SFT and SFT+Itafos and SFT+Gafsa can be an alternative to farming systems, aiming to lower use of acidulated phosphate. The yield performance of corn was not altered by the P sources and levels of inoculation with P. fluorescens. A utiliza o crescente de fertilizantes para elevar a disponibilidade de P para as plantas tem promovido um forte impacto econ mico no setor agrícola. Visando a melhor eficiência do uso dos fertilizantes fosfatados, este estudo teve como objetivo avaliar o efeito de fontes de P associados à inocula o com Pseudomonas fluorescens via sementes, no desenvolvimento e nos componentes de produ o de plantas de milho. O experimento foi conduzido a campo, em esquema fatorial 6x2, em blocos casualizados, com quatro repeti es. Foram aplicados 120 kg ha-1 de P via solo por meio de seis fontes: Superfosfato Triplo (SFT), Gafsa, Itafós, SFT+Gafsa e SFT+Itafós, além do controle (sem P). As sementes da cultivar AG 8088 foram submetidas à inocula o ou n o com Pseudomonas fluorescens da Estirpe 1008. As variáveis analisadas no florescimento foram: altura de plantas (AP), altura da inser o da espiga (AIE), diametro do colmo (DC), área foliar (AF), massa seca de folhas (MSF), massa seca total (MST)