Fruit Yield in Cucumber Grafted on Different Rootstocks

Grafting is an alternative technique often recommended for cucumber culture in protected environments. This study aimed to study yield of cucumber grafted on different rootstocks compared to non-grafted plants in non-infected soil. Five treatments (Japanese cucumber hybrid 'Tsuyataro' without grafting, grafted on squash hybrids 'Shelper', 'Excitte Ikki', 'Daiguy' and 'Keiji') were evaluated in a completely randomized blocks design, with four repetitions and six plants per plot. Lesser fruit yield was obtained in cucumber grafted on 'Keiji', while cucumber grafted on other rootstocks did not differ from non-grafted plants. So, in the absence of soil borne diseases, grafting did not increase cucumber fruit yield, and, depending on rootstock, grafting can decrease production compared with non grafted plants.

Growth and development of Mentha piperita L. in nutrient solution as affected by rates of potassium

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Phosphate forms in plant and their internal buffering in five soybean cultivars

Diferenças inter e intra-específicas na habilidade de suportar períodos de estresse nutricional podem dever-se à capacidade de armazenar e liberar íons dos vacúolos, e, ou, à intensidade de retranslocação de nutrientes em tais condições. Neste trabalho, pretendeu-se avaliar diferenças varietais quanto ao tamanho do pool não-metabólico de Pi; velocidade de liberação do Pi previamente armazenado (VLPi), quando o P citoplasmático cai a um valor limite; capacidade de transportar Pi de regiões menos ativas para aquelas mais ativas metabolicamente e definir compartimentos que são preferencialmente fontes e os que são preferencialmente drenos para o Pi, em condições de absorção limitada de P. Avaliaram-se a produção de matéria seca e os teores internos de Pi, orgânico (Po) e total solúvel em ácido (Pts), de diferentes órgãos de plantas dos cultivares de soja (Glycine max L. Merrill) Santa Rosa, Uberaba, IAC8, Doko e UFV1, submetidos a oito dias de omissão do elemento. A VLPi foi estimada como tangente às equações obtidas para Pi como função do perído de omissão no ponto médio do período de omissão em que houve maior decréscimo em Pi (zero a quatro dias de omissão de P), t = dois dias, considerando-se que -deltaPi/deltat expressa a velocidade de liberação de Pi. A capacidade interna de tamponamento de Pi (CTIPi) foi calculada como o inverso da VLPi. O cultivar Santa Rosa apresentou maior capacidade de armazenar Pi, quando o suprimento externo foi alto, liberando-o mais intensamente sob condições de baixo suprimento de P que os cultivares IAC8 e UFV1. O cultivar Uberaba mostrou-se superior ao Doko em sua habilidade de armazenar e utilizar o Pi. Folhas superiores mostraram ser o principal dreno para o Pi armazenado em folhas medianas e inferiores, seguidas por raízes e caules. Raízes comportaram-se como fontes ou drenos para o Pi. Raízes e folhas superiores apresentaram maiores (VLPi) e menores valores de CTIPi que folhas medianas e folhas inferiores, sendo o caule o compartimento com menor VLPi e maior CTIPi. Dentre as variedades, as diferenças foram pequenas, destacando-se a maior VLPi e menor CTIPi do cultivar Santa Rosa. O cultivar Doko apresentou a menor VLPi e maior CTIPi, enquanto Uberaba, IAC8 e UFV1 ocuparam posição intermediária quanto a essas características.

Eficiência de argila silicatada no controle de Xanthomonas axonopodis pv. passiflorae, in vitro e em mudas de maracujazeiro-amarelo

A mancha bacteriana do maracujá, causada pela bactéria Xanthomonas axonopodis pv. passiflorae, ocorre em todas as regiões produtoras do País, sendo responsável por grandes perdas econômicas na cultura do maracujazeiro-amarelo. O presente trabalho teve como objetivos testar a eficiência de argila silicatada na inibição da bactéria X. axonopodis pv. passiflorae in vitro e no controle preventivo e curativo da mancha bacteriana em mudas de maracujazeiro-amarelo. A argila silicatada foi adicionada ao meio de cultura batata-dextrose-ágar fundente, nas concentrações de 0,0; 0,5; 1,0; 1,5 e 2,0%; vertido em placas de Petri. Após resfriamento do meio, repicou-se a suspensão bacteriana (10(7) UFC.mL-1) com uma alça, incubando-se as placas a 28 °C por três dias, quando se avaliou o crescimento bacteriano. Posteriormente, o produto, nas mesmas concentrações citadas, foi pulverizado em mudas de maracujá 'Afruvec' de forma preventiva ou curativa. A inoculação da bactéria foi realizada através de pulverização foliar da suspensão bacteriana (10(7) UFC.mL-1), 24 h antes ou após os tratamentos curativo e preventivo, respectivamente. A severidade da doença foi avaliada com auxílio de uma escala diagramática nas quatro primeiras folhas verdadeiras contadas de baixo para cima. Nas concentrações avaliadas, a argila silicatada inibiu a bactéria in vitro e os sintomas da mancha bacteriana no tratamento curativo, enquanto no tratamento preventivo, controle significativo foi obtido a partir de 1,0% de argila silicatada. Com base nestes resultados, a argila silicada pode ser recomendada, na concentração de 1,0-2,0%, para o controle da mancha bacteriana do maracujazeiro em pulverizações foliares.

Analysis of the efficiency of silicate clay on the control of Xanthomonas axonopodis PV. passiflorae in vitro and in seedlings of yellow passion fruit contaminated

The bacterial spot in yellow passion fruit plants, caused by the bacteria Xanthomonas axonopodis pv. passiflorae, occurs in all producing areas of the country, and is responsible for great economic losses in the culture of passion fruit. This study aimed to test the efficiency of the silicate clay in the inhibition of the bacteria Xanthomonas axonopodis pv. passiflorae in vitro, and in both preventive and curative control of the bacterial spot in seedlings of yellow passion fruit plants. The silicate clay was added to the growth medium at concentrations of. 0.5, 1.0, 1.5 and 2.0%, placed in Petri dishes. After the culture medium was cooler, the bacterial suspension was inoculates (10(7) UFC.mL(-1)) with a handle, and left incubating at 28 degrees C for three days, and then the bacterial growth was evaluated. Subsequently, the product at the same concentrations above was sprayed on seedlings of 'Afruvec' passion fruit, as preventive or curative. The inoculation of the bacteria was made by foliar spraying of bacterial suspension (10(7) ufc.mL(-1)), 24 hours before or after the curative and preventive treatments, respectively. The severity of the disease was measured comparing each four true leaves from bottom up, with a diagrammatic scale. In the concentrations evaluated, the silicate clay inhibited both bacteria in vitro and symptoms of bacterial spot in the curative treatment. In preventive treatment, significant results were obtained using more than 1.0% of clay silicates. Based on these results, the clay silicate can be recommended, the concentration of 1.0-2.0% for the control of bacterial spot of passion fruit plants, in foliar sprays.

Caracterização in situ e diversidade genética de algodoeiros mocós (Gossypium hissutum raça marie galante) da Região Nordeste do Brasil

Brazil is one of the major centers of diversity for polyploid cotton plants; these plants belong to the genus Gossypium, which has three known species: G. hirsutum, G. barbadense and G. mustelinum. The Northeast is the only region where the three species occur, the last group being endemic. Northeast s cotton plants can be important sources of variability for genetic breeding. It is believed that great part of local diversity is being lost, due to economic, political, cultural and agricultural problems. In an attempt to mitigate this loss and delineate conservation strategies it is necessary to know how the species are found where they occur. The objective was to characterize and determine how plants are maintained in situ in the states of Maranhão, Piauí, Ceará, Rio Grande do Norte and Paraíba at the beginning of the XXI century. The in situ characterization of G. hirsutum and G. barbadense was conducted through structured interviews with the cotton plants owners and through the analysis of the environment. The data were collected during expeditions undertaken between the years 2004 to 2005. Twenty-two plants were collected in the state of Paraíba, forty-four in the state of Rio Grande do Norte, one hundred and forty-six in the state of Ceará, forty in the state of Maranhão and ninety-one plants in the state of Piauí. All plants collected in the states of Paraíba and Rio Grande do Norte belonged to moco type. Moco cotton plants also predominated in the other states, representing 92%, 62% and 78% of plants collected in Ceará, Piauí and Maranhão, respectively. The other cotton plants collected belong to the species G. barbadense. The cotton plants were found in situ as dooryard plants, roads side, feral populations, cultivation or local varieties. Great part were dooryard plants (45.2%), being major in Piauí and Maranhão. Cultivation predominated in Ceará; in Rio Grande do Norte feral populations were the most frequent and, in Paraíba, local varieties. The maintenance of moco plants is related, mainly, to the phytotherapic domestic use (20.9%) and to confection of lamp wicks (29.7%). Few inhabitants in Paraíba, Rio Grande do Norte, Piauí and none in Maranhão used harvest the plants, storage the seeds or gin; however, in Ceará, 40.5% of owners affirmed that they harvested and commercialized the fiber. It was found that the maintenance of species is dependent of the fragile cultural habits of local inhabitants, therefore the maintenance in situ is not a suitable way to conservation of genetic resources. The efforts must be directed to the continuity of collections, maintenance and characterization ex situ

Caracterização genética e in situ de Gossypium barbadense na região norte do Brasil

Brazil has been considered one of the diversity centers of Gossypium barbadense species. It is believed that a relatively big erosion genetic process occurs with the species, due to economic, cultural and agricultural problems. A local diagnostic about species situation is the first step for reducing the diversity loss and establishing conservation strategies in situ. This research aimed the identification of the presence of Gossypium populations, characterization, determination of the main risks and collection of the accesses to store in germoplam banks, in Para and Amapa States. Expeditions were conducted in November 2004. An interview was carried out with the plant proprietor for characterizing in situ of G. barbadense species and of the environment where the plants were inserted. On hundred seventy nine plants in 22 municipal districts were collected in Para State and 117 plants in nine municipal districts in Amapa State. The majority of plants belong to G. barbadense species (98% in Amapa and 94% in Para). Plants occur in back yards, beside roads and spontaneously. That ones from back yards were more abundant (97% in Amapa and 95% in Para) and maintained as medicinal plants as the principal reason. Plants in natural environments in both states evaluated were not found, therefore, the creation of reserves and the application of others conventional methods of maintenance in situ are not applicable. The plant proprietors do not use to store or process seeds. Seed storage was reported as a practice by only 1% of the plant proprietors from Para and 11% from Amapa. The most plants collected were from two to three years of age (58% in Amapa and 93% in Para). As conclusions G. barbadense is the species most spread in the two studied states and are found in back yards. In Amapa State the botanical variety barbadense or Quebradinho is predominant, whereas in Para State the predominant variety is brasiliense or Rim-de-boi. Adequate conservation of thestudied species must be carried out in germoplasm collections maintained ex situ

Cancer risk assessment of ethyl carbamate in alcoholic beverages from Brazil with special consideration to the spirits cachaca and tiquira

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

First report of Trypanosoma vivax outbreak in dairy cattle in São Paulo state, Brazil

Esta é a primeira descrição de um surto de Trypanosomavivax ocorrido no Estado de São Paulo, no município de Lins. Animais acometidos apresentaram febre, icterícia, diminuição da produção de leite, perda de peso, diarreia profusa, abortos, anemia, leucocitose e hiperfibrigenemia. Foram registrados 31 óbitos de vacas e bezerros em 1.080 bovinos no total. Três vacas apresentaram sintomatologia nervosa, como dismetria, ataxia e fraqueza muscular, além de ptialismo, aumento de linfonodos e edema submandibular. Hemoparasitas flagelados foram observados em esfregaços sanguíneos, e a espécie de tripanossomo foi diagnosticada como T.vivax por PCR. A cepa de T. vivax mostrou ser resistente ao tratamento com aceturato de diaminozeno e a infecção disseminou rapidamente no rebanho. Pelo ELISA, observou-se que 98,36% (599) das amostras de soro colhidas apresentaram títulos positivos para IgG anti-T.vivax. O surto ocorreu em condições de baixa precipitação pluviométrica, fato que indica que outros fatores estavam envolvidos na ocorrência desse surto, como a ausência de tabanídeos e a grande presença de Haematobia irritans e Stomoxys calcitrans, cujo aumento populacional pode ser devido ao uso de resíduos de usinas de açúcar e álcool nos canaviais que circundavam a granja leiteira.

Growth and photosynthetic down-regulation in Coffea arabica in response to restricted root volume

Coffee (Coffea arabica L.) plants were grown in small (3-L), medium (10-L) and large (24-L) pots for 115 or 165 d after transplanting (DAT), which allowed different degrees of root restriction. Effects of altered source : sink ratio were evaluated in order to explore possible stomatal and non-stomatal mechanisms of photosynthetic down-regulation. Increasing root restriction brought about large and general reductions in plant growth associated with a rising root : shoot ratio. Treatments did not affect leaf water potential or leaf nutrient status, with the exception of N content, which dropped significantly with increasing root restriction even though an adequate N supply was available. Photosynthesis was severely reduced when plants were grown in small pots; this was largely associated with non-stomatal factors, such as decreased Rubisco activity. At 165DAT contents of hexose, sucrose, and amino acids decreased in plants grown in smaller pots, while those of starch and hexose-P increased in plants grown in smaller pots. Photosynthetic rates were negatively correlated with the ratio of hexose to free amino acids, but not with hexose content. Activities of acid invertase, sucrose synthase, sucrose-P synthase, fructose-1,6- bisphosphatase, ADP-glucose pyrophosphorylase, starch phosphorylase, glyceraldehyde-3-P dehydrogenase, PPi : fructose-6-P 1-phosphotransferase and NADP : glyceraldehyde-3-P dehydrogenase all decreased with severe root restriction. Glycerate-3-P : Pi and glucose-6-P : fructose-6-P ratios decreased accordingly. Photosynthetic down-regulation was unlikely to have been associated directly with an end-product limitation, but rather with decreases in Rubisco. Such a down-regulation was largely a result of N deficiency caused by growing coffee plants in small pots.

Boron transport in Eucalyptus. 2. Identification in silico of a putative boron transporter for xylem loading in eucalypt

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

Identification of suitable internal control genes for expression studies in Coffea arabica under different experimental conditions

Background: Quantitative data from gene expression experiments are often normalized by transcription levels of reference or housekeeping genes. An inherent assumption for their use is that the expression of these genes is highly uniform in living organisms during various phases of development, in different cell types and under diverse environmental conditions. To date, the validation of reference genes in plants has received very little attention and suitable reference genes have not been defined for a great number of crop species including Coffea arabica. The aim of the research reported herein was to compare the relative expression of a set of potential reference genes across different types of tissue/organ samples of coffee. We also validated the expression profiles of the selected reference genes at various stages of development and under a specific biotic stress.Results: The expression levels of five frequently used housekeeping genes (reference genes), namely alcohol dehydrogenase (adh), 14-3-3, polyubiquitin (poly), beta-actin (actin) and glyceraldehyde-3-phosphate dehydrogenase (gapdh) was assessed by quantitative real-time RT-PCR over a set of five tissue/organ samples (root, stem, leaf, flower, and fruits) of Coffea arabica plants. In addition to these commonly used internal controls, three other genes encoding a cysteine proteinase (cys), a caffeine synthase (ccs) and the 60S ribosomal protein L7 (rpl7) were also tested. Their stability and suitability as reference genes were validated by geNorm, NormFinder and BestKeeper programs. The obtained results revealed significantly variable expression levels of all reference genes analyzed, with the exception of gapdh, which showed no significant changes in expression among the investigated experimental conditions.Conclusion: Our data suggests that the expression of housekeeping genes is not completely stable in coffee. Based on our results, gapdh, followed by 14-3-3 and rpl7 were found to be homogeneously expressed and are therefore adequate for normalization purposes, showing equivalent transcript levels in different tissue/ organ samples. Gapdh is therefore the recommended reference gene for measuring gene expression in Coffea arabica. Its use will enable more accurate and reliable normalization of tissue/organ-specific gene expression studies in this important cherry crop plant.

Evolutionary dynamics of rRNA gene clusters in cichlid fish

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

Seed rain and seed limitation in a planted gallery forest in Brazil

With seeds collected monthly during one year from 53 1-m(2) seed traps, we investigated the seed rain and seed limitation in a gallery forest planted in 1994 in SE Brazil. Contrasting animal- (zoochorous) and wind-dispersed (anemochorous) plants we investigated (1) which aspects of the composition and structure of the vegetation influence the abundance and species richness of the seed rain; (2) if such influences differ between zoochorous and anemochorous seeds; (3) if the abundance and richness of the seed rain sampled under zoochorous and nonzoochorous plant species differ; and (4) if seed limitation (given by the proportion of sites to which seeds were not dispersed) differs between zoochorous and anemochorous plant species, and also between species that have been planted and those that further colonized the area (colonists). Seed rain was intense and dominated by anemochorous species. The overall seed rain was not influenced by the vegetation parameters we analyzed (canopy height and cover, plant size, abundance, and richness) or by the plant species above the seed trap. The abundance and richness of zoochorous seeds in a given spot was influenced by the abundance and richness of zoochorous plants in its immediate vicinity. Seed limitation was higher for anemochorous than zoochorous species and higher for planted than for colonist species. We concluded with recommendations for the initial establishment of a planted forest, including the homogeneous distribution of zoochorous plants to permit a spatially homogeneous zoochorous seedfall, which will likely enhance the chances of survival and successful establishment of seeds.

Comparative gas exchange performance during the wet season of three Brazilian Styrax species under habitat conditions of cerrado vegetation types differing in soil water availability and crown density

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