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A produção de orquídeas do gênero Phalaenopsis tem crescido nos últimos anos devido principalmente ao seu rápido crescimento e a produção de hastes florais com uma grande variedade de cores. Entre os fatores que afetam o crescimento e desenvolvimento destas plantas, a adequada nutrição é fundamental para obtenção de mudas de qualidade. O objetivo do trabalho foi avaliar o efeito de doses de osmocote® (15-09-12-N-P2O5-K2O, respectivamente) no desenvolvimento inicial da orquídea Phalaenopsis sp. O fertilizante osmocote® foi adicionado nas seguintes doses: 0, 2, 4, 6, 8 e 10 g vaso-1. Após doze meses foram avaliados: comprimento e largura média das folhas, área foliar total, massa seca da parte aérea e raiz e teores de clorofila a, b e carotenoides. Dos substratos foram avaliados o pH e a condutividade elétrica. O comprimento e largura das folhas atingiram seu máximo nas doses de 4,7 e 5,0 g vaso-1, respectivamente. Para massa seca de folhas, raizes e área foliar total, as doses de máxima eficiência estimada foram 4,6, 3,5 e 4,5 g vaso-1, respectivamente. O aumento nas doses de Osmocote® acarretou na morte das plantas na aplicação de 10 g vaso-1. Doses estimadas entre 3,5 a 5,1 g vaso-1 de Osmocote® (15-09-12) são recomendadas no desenvolvimento inicial da orquídea Phalaenopsis sp. por proporcionar incrementos na altura, largura, área foliar, massa seca da planta e nos pigmentos fotossintetizantes. Doses acima de 6 g vaso-1 foram prejudiciais ao desenvolvimento devido ao aumento da condutividade elétrica e redução do pH

Soybean and maize are some of the main drivers of Brazilian agribusiness. However, biotic and abiotic factors are of great concern, causing huge grain yield and quality losses. Phosphorus (P) deficiency is important among the abiotic factors because most Brazilian soils have a highly P-fixing nature. Thus, large amounts of phosphate fertilizers are regularly applied to overcome the rapid precipitation of P. Searching for alternatives to improve the use of P by crops is essential to reduce the demand for P input. The use of multifunctional rhizobacteria can be considered one of these alternatives. In this sense, the objective of the present work was to select and validate bacterial strains with triple action (plant growth promoter, phosphate solubilizer, and biocontrol agent) in maize and soybean, aiming to develop a multifunctional microbial inoculant for Brazilian agriculture. Bacterial strains with high indole acetic acid (IAA) production, phosphate solubilization, and antifungal activity against soil pathogenic fungi (Rhizoctonia solani, Macrophomina phaseolina, and Fusarium solani) were selected from the maize rhizosphere. Then, they were evaluated as growth promoters in maize under greenhouse conditions. Based on this study, strain 03 (Ag75) was selected due to its high potential for increasing biomass (root and shoot) and shoot P content in maize. This strain was identified through genomic sequencing as Bacillus velezensis. In field experiments, the inoculation of this bacterium increased maize and soybean yields by 17.8 and 26.5%, respectively, compared to the control (25 kg P2O5). In addition, the inoculation results did not differ from the control with 84 kg P2O5, indicating that it is possible to reduce the application of phosphate in these crops. Thus, the Ag75 strain has great potential for developing a multifunctional microbial inoculant that combines the ability to solubilize phosphate, promote plant growth, and be a biocontrol agent for several phytopathogenic fungi.

Studies showed that intercropping garlic reduced pests in strawberry field crops. However, influence of intercropping on yield was not tested. The objective of the study was to evaluate the strawberry pseudofruit and garlic bulb productions in monocropping and intercropping systems. Assessments of the yields and calculation of the land equivalent ratio, competition ratio and gross income were performed. The experiments were conducted in three areas (two open field and one greenhouse) in Londrina municipality. Treatments in the field experiments were garlic or strawberry in monocrops (controls), strawberry (S) + one garlic row (GR), S + 2GR or S + 3GR per plot. In the greenhouse experiment, plants were grown in pots with following treatments: garlic or strawberry in monocrops, 2S + 2 garlic plants per plot (GPP), 2S + 4GPP or 2S + 5GPP. Similar yields (garlic bulbs and strawberry pseudofruits) were observed among the treatments. Intercropping garlic among strawberry plants increased the land equivalent ratio. The intercrop land equivalent ratio index ranged from 1.34 to 2.55. An increasing in gross income were observed when increasing garlic plant densities in intercropping with strawberry. Results showed that intercropping garlic with strawberry increases land equivalent ratio and gross income. Production of strawberry pseudofruits and garlic bulbs were not influenced by intercropping systems compared to monocropping.