Produção e caracterização fisico-quimica de morango (Fragaria X Ananassa Duch) sob diferentes fontes de adubação fosfatada Production and physical and chemical characterization of strawberry (Fragaria X Ananassa Duch) under different sources of phosphate fertilization

In the establishment of coffee crops, phosphate fertilization is one of the most important soil fertility managements. Aiming to minimize losses, among the options in use are fertilizers with a slow release of nutrients, combined with the inoculation of arbuscular mycorrhizal fungi (AMF). This study aimed to evaluate the initial growth of coffee plants inoculated with AMF and submitted to different types of phosphate fertilizers. The experiment was conducted in a greenhouse, using a complete randomized block design, in a 2 x 4 factorial scheme, with four replications. The first factor referred to the presence or absence of AMF (Rhizophagus clarus) and the second one to phosphate [monoammonium phosphate (MAP)], pelletized organomineral and grainy organomineral fertilizers, as well as a control (without fertilization). The plant height, leaf chlorophyll content, number of plagiotropic branches, leaf area, shoot and root dry matter mass, percentage of root colonization and leaf phosphorus were evaluated. The inoculation with AMF, associated with the pelletized organomineral fertilizer, provided a higher growth for the shoot and root system and higher phosphorus contents, in relation to the other treatments, and it can be an alternative to the implantation or renewal of coffee crops.

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.

No abstract

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

No abstract

The objective of this study was to evaluate the growth and quality of arabica coffee seedlings produced in tubes under different sources of phosphorus (P). The experiment was conducted in a greenhouse in a randomized block design with ten treatments (control, Osmocote®, three doses of pelleted organomineral, three doses of mashed organomineral, MAP, coated MAP) and four replications, three plants per plot. The dose of organomineral, MAP, and MAP coated was based on the recommendation of P2O5 for the formation of coffee seedlings. For Osmocote®, the manufacturer's recommendation was used depending on the amount, in dm³, of substrate. After 180 days of transplanting, the growth characteristics of the plants (leaf dry matter, stem, and roots) were evaluated, and the aerial part and root system ratio and Dickson's quality index were calculated, as well as regression equations were adjusted for the evaluated parameters. For the growth and quality of seedlings, it was observed that in fertilizations with pelleted and branched organomineral, coated MAP and Osmocote®, the highest averages were obtained for the contents of dry matter, height, diameter of the collection and quality indexes, when compared to the other sources of P2O5. The dose that provides the maximum growth and quality of coffee seedlings for the treatments with organomineral was calculated, this being equal to 6 g/dm³ of P2O5 for bran and pelleted organomineral. According to the results, the sources that promoted the formation of a vigorous seedling, with an adequate supply of nutrients and a good quality standard are pelleted organonineral fertilization and MAP, reducing the risk of losses and consequently the need to discard the seedlings in the nursery.