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The variability of growth patterns and capacity to resist to environmental stresses that exists in populations of Coffea canephora Pierre ex Froehner makes it possible to select genotypes for different types of cultivation conditions. The objective of this study was to evaluate the monthly growth rate as a criterion to measure the genetic diversity of genotypes and to estimate the direct and indirect effects of the monthly growth rate, by path analysis, over the length of orthotropic stems. The experiment followed a randomized complete block design, studying 10 genotypes of C. canephora Pierre ex A. Froehner, with four replications and six plants per experimental plot. The magnitudes of the direct and indirect effects observed in the path analysis are consistent indicatives that the growth rate during recovery months, in the peaks after periods of slower growth, is highly important to determine the length of the stems during the final of the season. There is a considerable level of similarity between the growth of genotypes from the same group regarding ripening cycle; however, the high variability makes possible to identify genotypes from different behaviors regardless of the group. Key words: Conilon coffee, orthotropic stems, genetic parameters, variability.

The objective of this study was to quantify the nutritional efficiency and responsiveness in relation to nitrogen of twelve genotypes of physic nut (Jatropha curcas L.) grown in soil without nitrogen supply and also with three levels of fertilization in a controlled environment. The experiment was conducted in factorial scheme 12 × 4 with four replications, the factors being: 12 genotypes of physic nut and four levels of nitrogen fertilization, studied in a randomized design. The plants were grown in pots, without restrictions, for 100 days and their dry matter and N contents were evaluated (for roots, leaves and total). Subsequently, the efficiency ratios for absorption, translocation, use and responsiveness in relation to the N supply were calculated. Overall, the nutritional efficiencies for nitrogen increase linearly with the increase of nitrogen supply in the soil. The genotypes CNPAE 161-II, CNPAE 167-II, CNPAE 180-I, CNPAE 255-I and CNPAE 300-I were classified as efficient and responsive to nitrogen fertilization being highlighted for plant breeding programs aiming to improve this agronomic trait. Key words: Physic nut, mineral nutrition, alpha parameter.

Reduced soil fertility has been surpassed by the supply of mineral nutrients, which results in increased rates of plant production and costs. In this context, the optimization of plants’ nutritional efficiency is critical to increase productivity and reduce the cost of agricultural production systems. The nutritional efficiency of plants is conditioned by numerous factors and the growing environment. Therefore, the knowledge of genetic basis and mode of inheritance can assist in selecting genotypes with desirable agronomic characteristics coupled with nutritional efficiency and genetic variability. The trend of expanding agricultural frontiers has increased interest in the use of genotypes with the potential to adapt to adverse conditions of soil fertility. Within crops, the coffee beans are the second most traded commodity in the world. In this sense, optimization of nutritional efficiency of the coffee has a positive impact on the sum of efforts to make sustainable activity. This review aimed to present a systematic analysis of the nutritional efficiency of the coffee. Key words: Nutrient absorption and utilization, root length, genetic variability.

A correção do solo e adubação são práticas agrícolas imprescindíveis para obtenção de boas produtividades. As culturas da mamoneira e pinhão-manso, embora adaptáveis a uma gama de ambientes, apresentam-se sensíveis a deficiências minerais e a acidez, carecendo ainda de mais estudos.Diante do exposto, objetivou-se avaliar o desenvolvimento inicial do pinhão-manso e da mamona submetidos a diferentes corretivos e doses de fósforo Foram realizados dois ensaios (1-mamona; 2- pinhão-manso) em casa de vegetação utilizando vasos plásticos como recipiente. O delineamento experimental utilizado foi em blocos casualizados, com dez tratamentos e quatro repetições, distribuídos em esquema fatorial 2 x 5, sendo os fatores: dois tipos de correções (calcário; calcário + óxido de magnésio), cinco doses de adubação fosfatada (50, 100, 150, 200 e 250% da dose recomendada), totalizando 40 unidades experimentais, para cada experimento. Em ambas as culturas o efeito da combinação calcário + óxido de magnésio proporcionou resposta semelhante a aplicação com calcário. No geral não houve influência no desenvolvimento inicial, da mamona e pinhão-manso, com aplicação de fósforo a níveis acima de 100%