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Lettuce is an annual herbaceous plant, native to the mild climate regions of the northern Mediterranean. Lettuce varieties can likely be developed well in mild temperatures, but the cold and frosty winds of the autumn/winter season may damage the leaves. Their cultivation under low tunnels is an alternative to reduce this problem. This study was carried out with the aim of evaluating the influence of different cropping systems on the productive performance of lettuce in the autumn/winter cropping season. The experiments were installed following a split plot scheme with three cropping systems: (i) Open field with black polyethylene mulching (BPM); (ii) low tunnel (LT); (iii) Open field cropping (OFC) system without BPM. Three lettuce varieties of different groups were used in the subplots, with a total of nine treatments. The experimental design was of randomized blocks with four replications, at two altitudes (700 and 950 m). The number of leaves per plant, stem length, head diameter, fresh and dry matter mass per plant, leaf area index, and specific leaf area were evaluated. LT should be used for lettuce cultivation at an altitude of 950 m, as it provided higher productive performance in the autumn season. The use of the low tunnel provided for the production of lettuce plants with thinner leaves and better visual appearance, at an altitude of 700 m.

Iron (Fe) is essential for the maintenance of processes such as respiration and photosynthesis, thus being an important element for the plant production of cultivated or natural species. However, the combination of Fe and the acidity of acid rain creates favourable environments for the occurrence of oxy-reduction reactions, which transform Fe3+ into soluble forms (Fe2+), increasing the availability of this metal in the soil, causing direct and indirect effects on plant growth, development, and productivity. Fe can also affect the availability of other nutrients in the soil like nitrogen (N) and phosphorus (P), directly influencing plant growth. At an optimum concentration, Fe can increase the availability of N, while in high concentrations, it does not alter N content. However, Fe has a high affinity for P and in acid soils this metal is commonly found in high concentrations, thus Fe usually binds to P, making this macronutrient unavailable for uptake by the plant, thereby negatively affecting the plant’s metabolism. To promote the recovery of environments contaminated by toxic levels of Fe, the use of mycorrhizal associations, such as ectomycorrhizae, is considered a promising practice. Ectomycorrhizal (ECM) fungi developed three Fe absorption mechanisms to prevent its insolubility and toxicity: acidification of the medium, reduction of ferric to ferrous form, and secretion of iron-chelating molecules (melanins and siderophores). However, for host plants to obtain the benefits of fungi under conditions of Fe toxicity, it is necessary to carry out in vitro studies, using several sources of this metal. It is also extremely important to analyse the relationship of Fe with other nutrients in the medium, mainly N and P, since ECM fungi have intra and interspecific variations, and their growth is influenced by several abiotic factors.

Iron is an essential nutrient but is toxic in excess mainly under acidic conditions. Yeasts have emerged as low cost, highly efficient soil inoculants for the decontamination of metal-polluted areas, harnessing an increasing understanding of their metal tolerance mechanisms. Here, we investigated the effects of extracellular iron and acid pH stress on the dimorphism of Yarrowia lipolytica. Its growth was unaffected by 1 or 2 mM FeSO4, while a strong cellular iron accumulation was detected. However, the iron treatments decreased the hyphal length and number, mainly at 2 mM FeSO4 and pH 4.5. Inward cell membrane H+ fluxes were found at pH 4.5 and 6.0 correlated with a pH increase at the cell surface and a conspicuous yeast-to-hypha transition activity. Conversely, a remarkable H+ efflux was detected at pH 3.0, related to the extracellular microenvironment acidification and inhibition of yeast-to-hypha transition. Iron treatments intensified H+ influxes at pH 4.5 and 6.0 and inhibited H+ efflux at pH 3.0. Moreover, iron treatments inhibited the expression and activities of the plasma membrane H+-ATPase, with the H+ transport inhibited to a greater extent than the ATP hydrolysis, suggesting an iron-induced uncoupling of the pump. Our data indicate that Y. lipolytica adaptations to high iron and acidic environments occur at the expense of remodelling the yeast morphogenesis through a cellular pH modulation by H+-ATPases and H+ coupled transporters, highlighting the capacity of this non-conventional yeast to accumulate high amounts of iron and its potential application for bioremediation.

Main conclusion: Higher vacuolar proton pump activity may increase plant energy and nutrient use efficiency and provide the nexus between plant inoculation with Herbaspirillum seropedicae and growth promotion. Abstract: Global change and growing human population are exhausting arable land and resources, including water and fertilizers. We present inoculation with the endophytic plant-growth promoting bacterium (PGPB) Herbaspirillum seropedicae as a strategy for promoting growth, nutrient uptake and photosynthetic efficiency in rice (Oryza sativa L.). Because plant nutrient acquisition is coordinated with photosynthesis and the plant carbon status, we hypothesize that inoculation with H. seropedicae will stimulate proton (H+) pumps, increasing plant growth nutrient uptake and photosynthetic efficiency at low nutrient levels. Plants were inoculated and grown in pots with sterile soil for 90 days. Herbaspirillum seropedicae endophytic colonization was successful and, as hypothesized, inoculation (1) stimulated root vacuolar H+ pumps (vacuolar H+-ATPase and vacuolar H+-PPase), and (2) increased plant growth, nutrient contents and photosynthetic efficiency. The results showed that inoculation with the endophytic bacterium H. seropedicae can promote plant growth, nutrient uptake and photosynthetic efficiency, which will likely result in a more efficient use of resources (nutrients and water) and higher production of nutrient-rich food at reduced economic and environmental costs.

Serendipita indica (former Piriformospora indica) is a non-obligate endophytic fungus and generally a plant growth and defence promoter with high potential to be used in agriculture. However, S. indica may switch from biotrophy to saprotrophy losing its plant growth promoting traits. Our aim was to understand if the free-living stage growth conditions (namely C availability) regulate S. indica’s phenotype, and its potential as plant-growth-promoting-microbe (PGPM). We grew S. indica in its free-living stage under increasing C availabilities (2–20 g L–1 of glucose or sucrose). We first characterised the effect of C availability during free-living stage growth on fungal phenotype: colonies growth and physiology (plasma membrane proton pumps, stable isotopic signatures, and potential extracellular decomposing enzymes). The effect of the C availability during the free-living stage of the PGPM was evaluated on wheat. We observed that C availability during the free-living stage regulated S. indica’s growth, ultrastructure and physiology, resulting in two distinct colony phenotypes: compact and explorer. The compact phenotype developed at low C, used peptone as the major C and N source, and displayed higher decomposing potential for C providing substrates; while the explorer phenotype developed at high C, used glucose and sucrose as major C sources and casein and yeast extract as major N sources, and displayed higher decomposing potential for N and P providing substrates. The C availability, or the C/N ratio, during the free-living stage left a legacy to the symbiosis stage, regulating S. indica’s potential to promote plant growth: wheat growth promotion by the explorer phenotype was ± 40% higher than that by the compact phenotype. Our study highlights the importance of considering microbial ecology in designing PGPM/biofertilizers. Further studies are needed to test the phenotypes under more extreme conditions, and to understand if the in vitro acquired characteristics persist under field conditions.

Chronic myeloid leukemia (CML) is a clonal myeloproliferative disease, accounting for 15 to 20% of leukemias, with an incidence of one to two cases/100,000 inhabitants. In Brazil, the estimated incidence of leukemia is six cases/100,000 men and 4.28 cases/100,000 women. CML is characterized by the presence of the Philadelphia chromosome. At present, three types of tyrosine kinase inhibitors (TKI) are administered to treat CML patients in the Brazilian public national health system (NHS), called the Unified Health System (in Portuguese, “Sistema Unico de Saude”, SUS). Such treatments are only effective if patients adhere to strict dosage regimens; protocol improvements that increase patient adherence to treatment would have economic and health benefits for overburdened health care systems. Here, pharmacist-monitored treatment is assessed. In our study, we applied two questionnaires, one to assess the adherence to pharmacological treatment and another to assess the quality of life. All patients studied (n = 23) were diagnosed with CML at a local hospital in “Espirito Santo” State, the “Hospital Evangelico Vila Velha” (HEVV). Treatment adherence was significantly higher in pharmacist-monitored patients than in nonmonitored patients (p = 0.0135). The quality of life of CML patients was also analyzed, indicating that monitored patients had a lower number of symptoms/complaints during treatment periods than nonmonitored patients. Finally, improved treatment adherence also translated into better clinical conditions, particularly during the early stage of treatment (e.g., the first 4 months). The intervention of a clinical pharmacist is significant to obtain positive clinical results. Therefore, it is recommended that this protocol be included in the standard NHS treatment protocol CML patient outcomes to reduce the indirect and recurring costs to the health care system caused by nonadherence.

At relatively low concentrations, the element manganese (Mn) is essential for plant metabolism, especially for photosynthesis and as an enzyme antioxidant cofactor. However, industrial and agricultural activities have greatly increased Mn concentrations, and thereby contamination, in soils. We tested whether and how growth of Pisolithus tinctorius is influenced by Mn and glucose and compare the activities of oxidative stress enzymes as biochemical markers of Mn stress. We also compared nutrient accumulation, ecophysiology, and biochemical responses in Eucalyptus grandis which had been colonized by the ectomycorrhizal Pisolithus tinctorius with those which had not, when both were exposed to increasing Mn concentrations. In vitro experiments comprised six concentrations of Mn in three concentrations of glucose. In vivo experiments used plants colonized by Pisolithus tinctorius, or not colonized, grown with three concentrations of Mn (0, 200, and 1000 μM). We found that fungal growth and glucose concentration were correlated, but these were not influenced by Mn levels in the medium. The anti-oxidative enzymes catalase and glutathione S-transferase were both activated when the fungus was exposed to Mn. Also, mycorrhizal plants grew more and faster than non-mycorrhizal plants, whatever Mn exposure. Photosynthesis rate, intrinsic water use efficiency, and carboxylation efficiency were all inversely correlated with Mn concentration. Thus, we originally show that the ectomycorrhizal fungus provides protection for its host plants against varying and potentially toxic concentrations of Mn.

In nature, iron (Fe) occurs in abundance and ranks fourth among all elements on Earth’s surface. Still, its availability to plants is reduced, once this element is in the form of hydrated oxides, which can limit plant productivity and biomass production. On the other hand, in high concentrations, this essential micronutrient for the plants can become a toxic agent, increasing the environmental contamination. Fe is necessary for the maintenance of essential processes like respiration and photosynthesis, participating in the electron transport chain and in the conversion between Fe2+ and Fe3+, being a key element for carbon dioxide (CO2) fixation and, therefore, important for crop production of cultivated or natural species. The balance of Fe should be strictly controlled, because both its deficiency and its toxicity affect the physiological process of plants. In aerated soils Fe is present in the form of Fe3+, which is the oxidized form and is less available to plants, so these organisms have devel...

Background Chronic kidney disease (CKD) is the convergent point of several pathological processes, and its evolution is insidious and characterized by a progressive and irreversible loss of kidney function. This impaired function induces the accumulation of uremic toxins and individuals with terminal CKD often have altered physiological responses, including a persistent state of immuno-suppression and development of diseases. A better characterization and stratification of these patients with CKD in different immuno-compromised groups would contribute to more effective and personalized treatments. The focus of this study was to use two parameters to stratify patients with CKD into four separate groups that are representative of different immunological status. Methods Patients with CKD were chosen randomly and stratified into four separate groups according to the period of time receiving dialysis treatment and leukocyte blood counts. The amount of apoptotic CD4 T cells were measured in each group of patients, and clinical/hematological parameters were correlated by multivariate analysis with each group. Results Observations reveal that one of the four groups of patients with CKD (group 3) had more apoptotic CD4 T cells than the other group; this group also had an increased malnutrition inflammation score (MIS), an elevated Kt/V, and a higher incidence of smoking. Conclusion A simple two-parameter-based stratification strategy could be used to design effective immunological therapies that differentiate the degrees of immuno-suppression across groups of patients with CKD.

In commercial lettuce growing, the intensive cultivation of the soil results in an increase in weed populations, making it difficult to fully exploit the area and increasing production costs. Under such circumstances, the use of soil covers can minimize this problem. Consequently, the objective of this study was to evaluate the effects of different materials as soil covers on the agronomic performance of three lettuce cultivars. The experiment was arranged in randomized blocks, with treatments set in a subdivided plot scheme. Five types of soil cover (plots) were tested: no cover, black plastic, double white faced plastic, straw mulching and kraft paper and three Lettuce cultivars (subplots): loose-crested leaf group, iceberg lettuce group, with four replicates. Number of leaves per plant, stem length and diameter, head diameter, mass of fresh and total dry matter, fresh matter mass of leaves and stem were evaluated. For the Lisa and Americana lettuce groups, bed soil cover materials were more efficient when compared to the uncovered beds. For economic and environmental reasons, kraft paper is recommended as a bedding cover material for these cultivars. Variation in growth occurred between the lettuce cultivars, independently of the use of bedding cover. This occurred in the sequence: loose leaf > iceberg lettuce> loose-crested leaf group.

The fishery on Penaeidae shrimp is done all over the Brazilian coast, especially the seabob shrimp (Xiphopenaeus kroyeri). It is captured in large quantities in the Southeast and Southern Brazil. In order to study the population structure of X. kroyeri from Anchieta Municipality, Espirito Santo State, during the period from January to December 2008, monthly samplings with one-hour-long were conducted to verify the number of individuals, biomass, sex, total length and gonad maturity stage. The specimens had total length ranging from 2.96 to 9.96 cm, and females were larger than males. It is suggested that the population of X. kroyeri presents patterns of recruitment and reproduction similar to those of the Northeast region. The estimated size of first gonadal maturation was 4.5 and 6.9 cm for males and females, respectively. The fishing operates on a stock composed of predominantly adult males and juveniles and adult females. The mesh size of the nets and the high plant biomass in the fishing areas may be contributing to the increased catch of juveniles, undermining the recruitment of X. kroyeri.

Brazil is known for production and worldwide export of coffees. Study of adaptation of new progenies/cultivars of Arabica coffee ( C. arabica L.) with resistance to rust in mountainous edaphoclimatic conditions is important for crop renewal and also for new plantations. This study was performed in the mountainous region of the Espirito Santo state, Brazil, with 30 progenies/cultivars of Arabica coffee planted at 2.5 x 0.7 m spacing with four replicates and seven plants/plot. The objective of the study was to evaluate the adaptation of rust-resistance coffee genotypes and compare them with the standard cultivars (Yellow and Red Catuais), with regards to the characteristics of productivity, rust infection, productivity, sieve, aspect, plant vigor and yield according to the different maturity periods of the fruits. The results show that there are progenies/cultivars available with yields superior to Red and Yellow Catuais for the five different maturation periods. The progenies/cultivars present tolerance/resistance to rust, high plant vigor and good agronomic characteristics of the beans. These are options for new plantations or for renovation of crops for high harvest yield and do not required the use of pesticides.

Several pollutants interfere with plant metabolism and heavy metals (HMs) are one of the most common. The HM toxicity can cause plant growth retardation, inhibition of photosynthesis, induction and inhibition of enzymes, DNA damage, and the generation of oxidative stress. To avoid toxicity from HMs, plants developed a range of different response mechanisms acting in additive and/or synergistic ways. The plant protection against metal toxicity occurs through control of root uptake of metal and metal transport within the plant. Proteins such as ferritin, metallothioneins, and glutathione-derived peptides (phytochelatins) and organic molecules such as organic acids and phytate play an important role in plant storage and detoxification process in metal homeostasis; when these systems are overloaded, oxidative stress defense mechanisms are activated. Understanding the functioning of these mechanisms in climate change is of utmost importance to understanding the process of adaptation of plants to environmental changes and their use in bioremediation process. This chapter chapter briefly summarizes some recent aspects of biological, molecular, and proteomic mechanisms concerning the responses of plants to HMs.

Talitroides topitotum (Amphipoda) was introduced in Brazil by silviculture activities. Currently the species is distributed in the states of Parana, Rio de Janeiro and Sao Paulo. This paper describes the species' occurrence in the state of Espirito Santo. The objective of this study was to determine the interference of the edge effect on community structure of macroinvertebrates associated with leaf litter, where a T. topitotum female specimen was observed in coffee cultivations in March 2008.

Fruit color and odor are the main features regulating the rate of fruit predation and dispersal. The aim of this study was to analyze the effect of odor and color on fruit predators and dispersers. The present study was conducted in a 30ha area of secondary forest in Southeastern Atlantic Brazil. This area was divided into two transects, in which four points were marked with a 30m distance from each other. Each sampling point contained a total of 30 artificial fruit which belong to six different treatment groups, with five artificial fruit per group. Each group was randomly placed on the ground and that artificial fruit was checked every seven days. For each group of five fruit, 5mL of essence (vanilla or pineapple) were placed, and no essence was used in the control group. Artificial fruit was made with green and red nontoxic modeling clay, as well as artificial essences (vanilla and pineapple). A total of 960 fruits were used. Predated fruit equaled 26.9% (258 units), from which the red/pineapple had the highest predation rate (81.9%), followed by red/vanilla (46.3%), while green/control fruits were not predated. Throughout the experiment, bitten fruit and pecked fruit equaled 58.3% and 41.7%, respectively. No significant differences were recorded (x²=7.57, df=5, p=0.182) between bitten and pecked fruit. Fruit color and odor are important in attracting predators and dispersers, which explains the high rate of predation of red/vanilla and red/pineapple, and the absence of predated fruits in the green/control group. Regarding the potential disperser, there was no statistically significant difference between pecked fruit and bitten fruit. As a result, it should be taken into consideration that zoochory (mammalochory and ornithochory) is the most important dispersal; therefore, it should be concluded that birds are more attracted by color and mammals by odor. Rev. Biol. Trop. 60 (2): 925-931. Epub 2012 June 01.El olor y el color de los frutos son las características principales que regulan el nivel de consumo y la dispersión de las semillas. Este estudio tuvo como objetivo analizar el efecto que tiene el olor y el color de los frutos sobre los depredadores y dispersores de semillas. El área de estudio abarca 30ha de bosque secundario localizado en el Atlántico sureste de Brasil. Este espacio se dividió en dos sectores, en los cuales se marcaron cuatro puntos con una distancia de 30m entre sí. En cada punto de muestreo se utilizaron 30 frutos que se distribuyeron en seis tratamientos, con cinco frutos artificiales para cada tratamiento. Además, cabe resaltar que cada tratamiento se colocó en el suelo de forma aleatoria y que los frutos artificiales se verificaron cada siete días. Para cada grupo de cinco frutos se utilizaron 5mL de esencia (vainilla y ananá) y para el grupo de control no se utilizó ningún aditivo de olor. Los frutos se confeccionaron con plastilina atóxica de color verde y roja, además de esencias artificiales (ananá y vainilla), asimismo se obtuvieron 960 frutos. El nivel de frutos consumidos fue del 26.9% (258 unidades), de los cuales los rojos/ananá fueron los más consumidos (81.9%), seguidos del rojo/vainilla (46.3%), mientras que los verde/control no fueron comidos. Durante el experimento la tasa de frutos mordidos fue del 58.3% y de picoteados un 41.7%. No se registró una diferencia significativa (x²=7.57, gl=5, p=0.182) entre frutos mordidos y picoteados. El color y el olor de los frutos son aspectos importantes para atraer depredadores y dispersores, lo que explica los niveles de consumo de los frutos rojos/vainilla y rojo/ananá y la ausencia de frutos comidos en el tratamiento del verde/control. En cuanto al potencial dispersor, no hubo una diferencia estadística significativa entre frutos mordidos y picoteados, por lo que se debe tomar en cuenta que la dispersión principal es la zoocoria (ornitocoria y mamalocoria). Por lo tanto, se puede concluir que las aves son atraídas por el color y los mamíferos por el olor.