A prática do cultivo de milho sucessivo à beterraba tem apresentado retornos econômicos positivos aos produtores, sendo um dos fatores primordiais para o sucesso da atividade, a adubação. O estudo objetivou avaliar diferentes manejos de adubação nos aspectos quantitativos e qualitativos na cultura da beterraba, bem como seus efeitos residuais no cultivo do milho plantado em sucessão. O experimento foi conduzido no município de Diamantina-MG, em casa de vegetação, sob delineamento em blocos casualizados, com sete tratamentos, sendo controle (sem adubação), mineral, organomineral peletizado NPK 04-17-07 nas doses de 40, 80, 160 e 320% da recomendação para a cultura da beterraba, com quatro repetições. Avaliou-se altura de plantas, diâmetros longitudinal e transversal das raízes, clorofila A e B, peso de massa fresca e seca da parte aérea e raízes, produtividade, teor de sólidos solúveis e o tempo de prateleira. Na segunda etapa experimental, verificou-se o número de espigas por planta, peso por espiga, peso do sabugo, peso de 100 grãos e estimada a produtividade. Os dados foram submetidos à análise de variância e ao teste Tukey (p < 0,05) para comparação de médias. A análise de regressão foi feita diante as doses do fertilizante organomineral para produtividade de ambas as culturas. A utilização do fertilizante organomineral peletizado e torta de filtro no plantio proporcionam efeitos positivos ao desenvolvimento e produção de plantas de beterraba assim como para o milho em sucessão, mostrando-se alternativas viáveis à adubação mineral neste sistema.

The inoculation of coffee plants with arbuscular mycorrhizal fungi (AMF) may influence some of its physiological parameters, promoting benefits in the growth of newly planted coffee. The objective of this work was to evaluate the physiological responses of different cultivars of Coffea arabica inoculated with arbuscular mycorrhizal fungi. The experiment was conducted in a vegetation house in Diamantina, state Minas Gerais. The design was in randomized blocks, in a 3 x 4 factorial scheme, with four replications. The factors were composed of coffee seedlings of Rubi (MG 1192), Mundo Novo (IAC 379-19) and Catuaí Vermelho (IAC 144) cultivars, inoculated or not with FMA Rhizophagus clarus, Acaulospora colombiana and Mix composed by R. clarus and A. colombiana. At 150 days after transplantation, physiological characteristics such as photosynthetic rate, internal carbon concentration, stomatal conductance, transpiration rate, water use efficiency, internal carbon / atmospheric carbon ratio and percentage of mycorrhizal colonization were evaluated. AMF inoculation affected positively the physiology of coffee plants, increasing photosynthetic rate (A), stomatal conductance (Gs), transpiration, carbon consumed (∆CO 2), water use efficiency (EUA) and percentage of mycorrhizal colonization (%), as well as reducing the internal carbon concentration (Ci) for all combinations of AMF cultivars and species. The cultivar Rubi, when inoculated with R. clarus or Mix, obtained a higher percentage of colonization. The physiological activity of coffee plants is altered by symbiotic association, and their responses varied between AMF species and cultivars.

Crescimento inicial de milho submetido a diferentes manejos de adubação Initial growth of corn under different fertilization management

The inoculation of coffee plants with arbuscular mycorrhizal fungi (AMF) may influence some of its physiological parameters, promoting benefits in the growth of newly planted coffee. The objective of this work was to evaluate the physiological responses of different cultivars of Coffea arabica inoculated with arbuscular mycorrhizal fungi. The experiment was conducted in a vegetation house in Diamantina, state Minas Gerais. The design was in randomized blocks, in a 3 x 4 factorial scheme, with four replications. The factors were composed of coffee seedlings of Rubi (MG 1192), Mundo Novo (IAC 379-19) and Catuaí Vermelho (IAC 144) cultivars, inoculated or not with FMA Rhizophagus clarus, Acaulospora colombiana and Mix composed by R. clarus and A. colombiana. At 150 days after transplantation, physiological characteristics such as photosynthetic rate, internal carbon concentration, stomatal conductance, transpiration rate, water use efficiency, internal carbon / atmospheric carbon ratio and percentage of mycorrhizal colonization were evaluated. AMF inoculation affected positively the physiology of coffee plants, increasing photosynthetic rate (A), stomatal conductance (Gs), transpiration, carbon consumed (∆CO 2), water use efficiency (EUA) and percentage of mycorrhizal colonization (%), as well as reducing the internal carbon concentration (Ci) for all combinations of AMF cultivars and species. The cultivar Rubi, when inoculated with R. clarus or Mix, obtained a higher percentage of colonization. The physiological activity of coffee plants is altered by symbiotic association, and their responses varied between AMF species and cultivars.