Understanding the effects of crevice and galvanic corrosion for seawater desalination plants management

 This research revealed the differences that occur when two forms of corrosion occur simultaneously in comparison to the individual corrosions, crevice and galvanic. It was shown that two forms of corrosion can actually reduce the amount of damage caused in selected conditions.

Nanostructured liquid crystalline particle assisted delivery of 2,4-dichlorophenoxyacetic acid to weeds, crops and model plants

Routine agricultural practices are heavily dependent on the use of surfactants, many of which are toxic to humans and detrimental to the environment. In proof of concept work we have previously shown the potential of nanostructured liquid crystalline particles (NLCP) to safely interact with plant leaf cuticular surfaces with minimal impact on epicuticular waxes. Here we demonstrate the use of NLCP to effectively deliver the auxin herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) to plant leaves in laboratory and field studies. In the laboratory, the physiological stress responses of lupin, Lupinus angustifolius (L.) (Fabaceae) towards NLCP spray applications were shown to be much reduced in comparison with application of two common surfactants. Phytotoxicity assays of 2,4-D loaded NLCP were used to validate the herbicidal effects on Arabidopsis thaliana (L.) Heynth. (Brassicaceae) and established a similarity with that of surfactant assisted 2,4-D delivery when tested at a concentration of 0.1%. Field trials were conducted to test the efficacy of NLCP-assisted delivery of 2,4-D in comparison with commercial surfactants for the control of the invasive weed wild radish, Raphanus raphanistrum (L.) (Brassicaceae), in wheat, Triticum aestivum (L.) (Poaceae) crop fields. Compared against Estercide 800, a commercially available 2,4-D formulation, NLCP assisted delivery of 2,4-D was effective at low concentrations of 0.03% and 0.06%. The crop yield remained similar for all the tested concentrations and formulations of 2,4-D loaded NLCP and Estercide 800. This is the first report to directly show that, as an alternative to conventional methods, NLCP can be used under both laboratory and field conditions to successfully delivery an agrochemical.

Metal ion ligands in hyperaccumulating plants

Metal-hyperaccumulating plants have the ability to take up extraordinary quantities of certain metal ions without succumbing to toxic effects. Most hyperaccumulators select for particular metals but the mechanisms of selection are not understood at the molecular level. While there are many metal-binding biomolecules, this review focuses only on ligands that have been reported to play a role in sequestering, transporting or storing the accumulated metal. These include citrate, histidine and the phytosiderophores. The metal detoxification role of metallothioneins and phytochelatins in plants is also discussed.

Metabolite profiling reveals distinct changes in carbon and nitrogen metabolism in phosphate-deficient barley plants (Hordeum vulgare L.)

Plants modify metabolic processes for adaptation to low phosphate (P) conditions. Whilst transcriptomic analyses show that P deficiency changes hundreds of genes related to various metabolic processes, there is limited information available for global metabolite changes of P-deficient plants, especially for cereals. As changes in metabolites are the ultimate ‘readout’ of changes in gene expression, we profiled polar metabolites from both shoots and roots of P-deficient barley (Hordeum vulgare) using gas chromatography–mass spectrometry (GC-MS). The results showed that mildly P-deficient plants accumulated di- and trisaccharides (sucrose, maltose, raffinose and 6-kestose), especially in shoots. Severe P deficiency increased the levels of metabolites related to ammonium metabolism in addition to di- and trisaccharides, but reduced the levels of phosphorylated intermediates (glucose-6-P, fructose-6-P, inositol-1-P and glycerol-3-P) and organic acids (α-ketoglutarate, succinate, fumarate and malate). The results revealed that P-deficient plants modify carbohydrate metabolism initially to reduce P consumption, and salvage P from small P-containing metabolites when P deficiency is severe, which consequently reduced levels of organic acids in the tricarboxylic acid (TCA) cycle. The extent of the effect of severe P deficiency on ammonium metabolism was also revealed by liquid chromatography–mass spectrometry (LC-MS) quantitative analysis of free amino acids. A sharp increase in the concentrations of glutamine and asparagine was observed in both shoots and roots of severely P-deficient plants. Based on these data, a strategy for improving the ability of cereals to adapt to low P environments is proposed that involves alteration in partitioning of carbohydrates into organic acids and amino acids to enable more efficient utilization of carbon in P-deficient plants.

Hydropower Energy Simulation Using Mike 11 Model; A Case Study In South Germany's Small Run-Of-River Hydropower Plants

Renewable energy production is a basic supplement to stabilize rapidly increasing global energy demand and skyrocketing energy price as well as to balance the fluctuation of supply from non-renewable energy sources at electrical grid hubs. The European energy traders, government and private company energy providers and other stakeholders have been, since recently, a major beneficiary, customer and clients of Hydropower simulation solutions. The relationship between rainfall-runoff model outputs and energy productions of hydropower plants has not been clearly studied. In this research, association of rainfall, catchment characteristics, river network and runoff with energy production of a particular hydropower station is examined. The essence of this study is to justify the correspondence between runoff extracted from calibrated catchment and energy production of hydropower plant located at a catchment outlet; to employ a unique technique to convert runoff to energy based on statistical and graphical trend analysis of the two, and to provide environment for energy forecast. For rainfall-runoff model setup and calibration, MIKE 11 NAM model is applied, meanwhile MIKE 11 SO model is used to track, adopt and set a control strategy at hydropower location for runoff-energy correlation. The model is tested at two selected micro run-of-river hydropower plants located in South Germany. Two consecutive calibration is compromised to test the model; one for rainfall-runoff model and other for energy simulation. Calibration results and supporting verification plots of two case studies indicated that simulated discharge and energy production is comparable with the measured discharge and energy production respectively.

Allelopathic plants. 7. Sunflower (Helianthus annuus L.)

Sunflower is an annual dicotyledonous plant, herbaceous, erect and native of North America. It is thermo- and photo-insensitive, hence, can be grown round the year in sub-tropical and tropical countries. Only two spp. H. annuus and H. tuberosum are cultivated for food, remaining spp. are ornamentals, weeds and wild plants. However, H. annuus is allelopathic and inhibit the growth and development of other plants thus reducing their productivity. Much information is available about the allelopathic effects of sunflower crop on following crops in crop rotations. Although it is harmful to all crops, but, is less harmful to crops of Graminae family than other families. It seems that the harmful effects of sunflower in crop rotations are due to release and accumulation of root exudates during crop growth in soil. Soil incorporation of its fresh (green manure) or dry biomass in soil is inhibitory to both crops and weed spp. Several allelochemicals have been characterized from the H. annuus, which inhibit the seed germination and seedling growth of A. albus, A. viridis, Agropyron repens (Elymus repens), Ambrosia artemsiifolia, Avena fatua, Celosia crustata, Chenopodium album, Chloris barbara, Cynodon dactylon, D. sanguinalis, Dactyloctenium ageyptium, Digitaria ciliaris, Echinochloa crus-galli, Flaveria australasica, Parthenium hysterophorus, Portulaca oleracea, Sida spinosa, Trianthema portulacastrum, Veronica perisca the inhibitory effects of this crop may be used for weed management with less herbicides for sustainable agriculture.

Sourgrass densities affecting the initial growth and macronutrient content of coffee plants

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Physiological dose response of coffee (Coffea arabica L.) plants to glyphosate depends on growth stage

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Glyphosate has low toxicity to citrus plants growing in the field

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Characterization of the genetic variability among Caesalpinia pulcherrima (L.) Sw. (Fabaceae) plants using RAPD molecular markers

O flamboyanzinho (Caesalpinia pulcherrima, Fabaceae) é muito utilizado como cerca-viva e na arborização de ruas, parques e jardins. de florescimento exuberante, suas flores podem apresentar coloração rosa, laranja ou amarela, conforme a variedade. Como características florais são essenciais para a definição do valor comercial de espécies ornamentais, o objetivo principal do trabalho foi verificar a existência de polimorfismo entre plantas de C. pulcherrima, que produzem flores de diferentes colorações, por marcadores moleculares RAPD. Foram escolhidas aleatoriamente 30 plantas adultas, cultivadas no município de Jaboticabal, Estado de São Paulo, para a retirada de amostras foliares para a extração de DNA. Dentre essas matrizes, 20 possuem flores alaranjadas, oito, flores amarelas, e apenas duas produzem flores de coloração rosa. Dos 140 primers de RAPD avaliados, 94 foram capazes de ampliar fragmentos definidos, gerando 246 bandas, das quais se observou 100% de bandas monomórficas, indicando que nenhum dos primers utilizados detectou polimorfismo entre os tratamentos. Concluiu-se que a técnica para detecção de polimorfismo por marcadores RAPD não foi eficiente, e que existe a necessidade de se testarem marcadores moleculares mais específicos. Além disso, a característica morfológica cor de flor é, possivelmente, controlada por vários genes ou pela combinação deles.

Effects of plant density and proportion on the interaction between wheat with alexandergrass plants

A determinação das relações competitivas entre espécies de plantas requer delineamentos experimentais e métodos de análise apropriados. A hipótese da pesquisa foi que duas espécies crescendo em convivência têm comportamento de crescimento e desenvolvimento distintos em função da sua competitividade relativa. O objetivo desta pesquisa foi quantificar a competitividade relativa da cultura do trigo com o capim-marmelada através da medida dos efeitos da densidade e da proporção de plantas, usando experimentos em série substitutiva. Monoculturas foram cultivadas em densidades de 1, 3, 5, 10 e 15 plantas por caixa e analisadas por regressão dos dados de massa seca, em 2006. Experimento em mistura foi cultivado nas proporções trigo:capim-marmelada de 0:6, 1:5, 2:4, 3:3, 4:2, 5:1 e 6:0 plantas por caixa e analisado através de interpretação gráfica de características de crescimento e produção, em 2007. Ambos os experimentos foram realizados em delineamento completamente casualizado com quatro repetições. Capim-marmelada foi mais sensível que trigo à competição intraespecífica. Capim-marmelada foi levemente mais competitivo que trigo. Número e massa de espigas e número de afilhos foram as características do trigo mais afetadas pela interferência do capim-marmelada.

Description and key to the fifth-instars of some Cicadas (Hemiptera: Cicadidae) associated with coffee plants in Brazil

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Oviposition of Quesada gigas (Hemiptera: Cicadidae) in coffee plants

Branches of coffee-plant were collected in Sao Sebastiao do Paraiso County, Minas Gerais State, at the Experimental Station of the Agricultural Research Company (Empresa de Pesquisa Agropecuaria de Minas Gerais - EPAMIG), with the aim of studying various aspects of oviposition by Quesada gigas (Hemiptera: Cicadidae). The number of branches with Q. gigas egg nests was analyzed, as well as the number of nests per branch, the eggs per nest and the diameter of the egg nest location on the branch. The preference for oviposition either on alive or dry branches and the size of the egg were assessed. Egg-laying occurred only on dry branches. The mean of the branch diameter on which the egg nests occurred was 2.5 +/- 0.53 mm. The number of eggs per nest averaged 13.2 +/- 4.9, and the number of egg nests per branch was 2.2 +/- 1.74. The eggs were 1.9 +/- 0.08 mm long by 0.5 +/- 0.04 mm wide. The largest diameters of the branches containing egg nests were found on the upper third of the trees, as well as the greatest amount of branches with egg nests, of egg nests per branch and of eggs per nest. The correlation relationship between all of the experiment variables was positive.

Transmission of Citrus leprosis virus C by Brevipalpus phoenicis (Geijskes) to Alternative Host Plants Found in Citrus Orchards

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)