Metabolic profiles of six African cultivars of cassava (Manihot esculenta Crantz) highlight bottlenecks of root yield

Open Access Article; Published online: 17 Jan 2020Cassava is an important staple crop in sub‐Saharan Africa, due to its high productivity even on nutrient poor soils. The metabolic characteristics underlying this high productivity are poorly understood including the mode of photosynthesis, reasons for the high rate of photosynthesis, the extent of source/sink limitation, the impact of environment, and the extent of variation between cultivars. Six commercial African cassava cultivars were grown in a greenhouse in Erlangen, Germany, and in the field in Ibadan, Nigeria. Source leaves, sink leaves, stems and storage roots were harvested during storage root bulking and analyzed for sugars, organic acids, amino acids, phosphorylated intermediates, minerals, starch, protein, activities of enzymes in central metabolism and yield traits. High ratios of RuBisCO:phosphoenolpyruvate carboxylase activity support a C3 mode of photosynthesis. The high rate of photosynthesis is likely to be attributed to high activities of enzymes in the Calvin–Benson cycle and pathways for sucrose and starch synthesis. Nevertheless, source limitation is indicated because root yield traits correlated with metabolic traits in leaves rather than in the stem or storage roots. This situation was especially so in greenhouse‐grown plants, where irradiance will have been low. In the field, plants produced more storage roots. This was associated with higher AGPase activity and lower sucrose in the roots, indicating that feedforward loops enhanced sink capacity in the high light and low nitrogen environment in the field. Overall, these results indicated that carbon assimilation rate, the K battery, root starch synthesis, trehalose, and chlorogenic acid accumulation are potential target traits for genetic improvement

Predation of ants and termites by army ants, Nomamyrmex esenbeckii (Formicidae, Ecitoninae). in the Brazilian Amazon

In four different localities in the Brazilian Amazon we registered raids of army ants (Nomamyrmex esenbeckii). The prey were ants of the genera Atta, Odontomachus and Camponotus and termites of the genus Nasutitermes. The behavior of the army ant and its prey were registered. Our observations expand the number of prey recorded in the literature. It is possible that the dietary regime of these army ants is more flexible than previously believed and is related to food availability

Extração de macro e micronutrientes por frutos de quatro variedades de manga (Mangifera indica L.)

Quantities of nutrients removed by the harvest of mango fruits (Mangifera indica L.) of four varieties (Haden, Sensation, Tommy-Atkins and Edward) are presented. The orchard was nine years old, situated on an alfison in Piracicaba, SP, Brazil. The fruits were harvested 39, 55, 97, 108, 125 and 144 days from the initial stage of growth. The fruits were rinsed, dried, weighed, and analyzed for nutrient content by laboratory conventional methods. The authors concluded: Fruit growth followed the decreasing order: Edward, Haden, Tommy-Atkins and Sensation; The total amount of nutrients (macro and micronutrients) removed by each variety for the production of 15,000kg of fresh fruits by hectare amounted to: Haden 44kg, Sensation 29kg, Tommy-Atkins 40kg and Edward 39kg.Determinou-se o crescimento e a extração de nutrientes pelos frutos das variedades, Haden, Sensation, Tommy-Atkins e Edward, colhidos em sete épocas distintas, de um pomar de nove anos situado sobre uma "terra roxa estruturada" em Piracicaba, SP. Os frutos foram lavados, pesados e analisados para macro e micronutrientes. O crescimento dos frutos nas variedades obedece a seguinte ordem decrescente: Edward, Haden, Tommy-Atkins e Sensation. O conteúdo total de nutrientes nas variedades foi em ordem decrescente: Haden , Tommy-Atkins, Edward e Sensation

Low temperature behavior of poultry fat biodiesel:diesel blends

AbstractAs the worldwide consumption of poultry meat rises the use of poultry fat as a feedstock for biodiesel production becomes attractive considering economical and environmental reasons. However, poultry fat biodiesel still faces some restrictions due to its poor flow properties at low temperatures. In this study ethylic and methylic poultry fat biodiesels and their blends with diesel were evaluated in terms of flow properties. Modulated Temperature Differential Scanning Calorimetry (MT-DSC) was used to understand the physical meaning of properties as Cold Filter Plugging Point (CFPP), Pour Point (PP) and Cloud Point (CP), widely used in biodiesel characterization. Based on the MT-DSC studies, it was observed that the first crystallization peak temperature had values similar to CFPP and CP. This way CP was found to be associated with the first solidified material and not with the early formation of the first nuclei, as normally reported. On the other hand, these crystals already lead to the flow decrease, as indicate by the CFPP results. PP values were close to the second crystallization peak temperature, not being related to the complete solidification of the fuel

Aplicação de produtos químicos na repicagem da figueira

Como a repicagem de mudas de figueira (Ficus carica L. cv. Roxo de Valinhas) apresen ta frequentemente problemas no transplante, estudou-se o efeito de produtos químicos nesta fase crftica para a formação do figueiral. Procedeu-se aos tratamentos de redução da área foliar, pulverização com Transplantone 10 g/l água, Oed green (oxietileno docosanol) 40 ml/1 ,Good-rite peps (polisulfeto de polietíleno) 0,6 ml/l e Mobileaf 200 ml/l, além do controle. Redução da área foliar ou pulverização com oxietileno docasonol aumentaram a porcentagem de sobrevivência das figueiras transplantadas. Os produtos químicos não promoveram variações significativas na altura das mudas de figueira 'Roxo de Valinhos'. Auxinas componentes do Transplantone (naftalenacetamida e àcido naftalenacético) causaram aumento no número de folhas da figueira transplantada.This research deals with the effects of chemicals on, transplantation of Ficus carica L. cv. Roxo de Valinhos. Fig plants were sprayed with Transplantone (naphthaleneacetamide plusnaphtaleneacetic acid) 10 g/1 , Oed green (oxyethylene docosanol) 40 ml/1, Good-rite peps (polyethylene polysulfite) 0,6 ml/1, and Mobileaf 200 ml/1. A check treatment and aereduction to half of leaf area were also established. Reduction of leaf area and application of oxyethylene docosanol promoted higher plant survival. The chemicals did not affect the growth of transplanted plants. Auxins constituents of Transplantone increased leaf number of fig plants

Genetic Diversity Of Pacu And Piapara Broodstocks In Restocking Programs In The Rivers Paraná And Paranapanema (brazil)

The genetic diversity of Piaractus mesopotamicus (pacu) and Leporinus elongatus (piapara) broodstocks used in restocking programs in the rivers Paraná and Paranapanema is analyzed. One hundred and twenty specimens (two broodstocks of each species) from fish ponds in Palotina PR Brazil and in Salto Grande SP Brazil were assessed. Ten primers produced 96 fragments, comprising 68 (70.83%) and 94 (97.92%) polymorphic fragments for P. mesopotamicus and L. elongatus broodstocks, respectively. Differences (p <0.05) in the frequency of 15 and 27 fragments were detected for each species, without exclusive fragments. Shannon Index (0.347-0.572) and the percentage of polymorphic fragments (57.3%-94.8%) revealed high intra-population genetic variability for all broodstocks. Results of molecular variance analyses (AMOVA) showed that most variations do not lie between the broodstocks but within each broodstock (89%). Genetic (0.088 and 0.142) and identity (0.916 and 0.868) distance rates demonstrated similarity between the broodstocks of each species, corroborated by Fst (0.1023 and 010.27) and Nm (4.18 and 4.33) rates, with a slight genetic difference due to genic flux. High intrapopulation genetic variability and similarity between the broodstocks of each species was also detected, proving a common ancestry.3742365237

Lorentz-violating effects on topological defects generated by two real scalar fields

The influence of a Lorentz-violation on soliton solutions generated by a system of two coupled scalar fields is investigated. Lorentz violation is induced by a fixed tensor coefficient that couples the two fields. The Bogomol'nyi method is applied and first-order differential equations are obtained whose solutions minimize energy and are also solutions of the equations of motion. The analysis of the solutions in phase space shows how the stability is modified with the Lorentz violation. It is shown explicitly that the solutions preserve linear stability despite the presence of Lorentz violation. Considering Lorentz violation as a small perturbation, an analytical method is employed to yield analytical solutions.Comment: (9 pages, 11 figures

Seroprevalence of Kaposi Sarcoma–associated Herpesvirus and Other Serologic Markers in the Brazilian Amazon

To determine the presence of Kaposi sarcoma–associated herpesvirus (KSHV) and other serologic markers, we tested serum specimens of 339 Amerindians, 181 rural non-Amerindians, and 1,133 urban blood donors (13 Amerindians) in the Brazilian Amazon. High KSHV seroprevalence in children and inverse association with herpes simplex virus type 2 indicates predominant nonsexual transmission among Amerindians