Genetic diversity and molecular characterization of Cucumber mosaic cucumovirus (CMV) subgroup II infecting Spinach (Spinacia oleracea) and Pea (Pisum sativum) in Pothwar region of Pakistan / Diversidade genética e caracterização molecular do Cucumber mosaic cucumovirus (CMV) subgrupo II infectando espinafre (Spinacia oleracea) e ervilha (Pisum sativum) na região de Pothwar, Paquistão

Abstract Cucumber mosaic virus (CMV) is a tremendous threat to vegetables across the globe, including in Pakistan. The present work was conducted to investigate the genetic variability of CMV isolates infecting pea and spinach vegetables in the Pothwar region of Pakistan. Serological-based surveys during 2016-2017 revealed 31.70% overall CMV disease incidence from pea and spinach crops. Triple-antibody sandwich enzyme-linked immunosorbent assay (TAS-ELISA) revealed that all the positive isolates belong to CMV subgroup II. Two selected cDNA from ELISA-positive samples representing each pea and spinach crops were PCR-amplified (ca.1100 bp) and sequenced corresponding to the CMV CP gene which shared 93.7% nucleotide identity with each other. Both the sequences of CMV pea (AAHAP) and spinach (AARS) isolates from Pakistan were submitted to GenBank as accession nos. MH119071 and MH119073, respectively. BLAST analysis revealed 93.4% sequence identity of AAHAP isolate with SpK (KC763473) from Iran while AARS isolate shared maximum identity (94.5%) with the strain 241 (AJ585519) from Australia and clustered with some reference isolates of CMV subgroup II from UK (Z12818) and USA (AF127976) in a Neighbour-joining phylogenetic reconstruction. A total of 59 polymorphic (segregating) sites (S) with nucleotide diversity (π) of 0.06218 was evident while no INDEL event was observed in Pakistani isolates. The evolutionary distance of Pakistani CMV isolates was recorded as 0.0657 with each other and 0.0574-0.2964 with other CMV isolates reported elsewhere in the world. A frequent gene flow (Fst = 0.30478 <0.33) was observed between Pakistani and earlier reported CMV isolates. In genetic differentiation analysis, the value of three permutation-based statistical tests viz; Z (84.3011), Snn (0.82456), and Ks* (4.04042) were non-significant. The statistical analysis revealed the values 2.02535, 0.01468, and 0.71862 of Tajima's D, Fu, & Li's F* and D* respectively, demonstrating that the CMV population is under balancing selection.

Resumo Cucumber mosaic cucumovirus (CMV) é uma tremenda ameaça aos vegetais em todo o mundo, inclusive no Paquistão. O presente trabalho foi conduzido para investigar a variabilidade genética de isolados de CMV infectando vegetais de ervilha e espinafre na região de Pothwar, Paquistão. Pesquisas com base em sorologia durante 2016-2017 revelaram 31,70% da incidência geral da doença por CMV em safras de ervilha e espinafre. O ensaio de imunoabsorção enzimática em sanduíche de anticorpo triplo (TAS-ELISA) revelou que todos os isolados positivos pertencem ao subgrupo II do CMV. Dois cDNA selecionados de amostras positivas para ELISA representando cada safra de ervilha e espinafre foram amplificados por PCR (ca.1100 pb) e sequenciados correspondendo ao gene CMV CP que compartilhou 93,7% de identidade de nucleotídeo um com o outro. Ambas as sequências de isolados de ervilha CMV (AAHAP) e espinafre (AARS) do Paquistão foram submetidas ao GenBank como nos de acesso. MH119071 e MH119073, respectivamente. A análise BLAST revelou 93,4% de identidade de sequência do isolado AAHAP com SpK (KC763473) do Irã, enquanto o isolado AARS compartilhou a identidade máxima (94,5%) com a cepa 241 (AJ585519) da Austrália e agrupada com alguns isolados de referência do subgrupo II de CMV do Reino Unido (Z12818) e EUA (AF127976) em uma reconstrução filogenética vizinha. Um total de 59 sítios polimórficos (segregantes) (S) com diversidade de nucleotídeos (π) de 0,06218 foi evidente, enquanto nenhum evento INDEL foi observado em isolados do Paquistão. A distância evolutiva de isolados de CMV do Paquistão foi registrada como 0,0657 entre si e 0,0574-0,2964 com outros isolados de CMV relatados em outras partes do mundo. Um fluxo gênico frequente (Fst = 0,30478 < 0,33) foi observado entre os isolados de CMV do Paquistão e relatados anteriormente. Na análise de diferenciação genética, os valores de três testes estatísticos baseados em permutação viz, Z (84,3011), Snn (0,82456) e Ks * (4,04042) não foram significativos. A análise estatística revelou os valores 2,02535, 0,01468 e 0,71862 de Tajima's D, Fu, & Li's F * e D * respectivamente, demonstrando que a população de CMV está sob seleção de balanceamento.

Cucumber downy mildew and the mechanisms of host resistance: a review / 生物工程学报

The cultivation and production of cucumber are seriously affected by downy mildew caused by Pseudoperonospora cubensis. Downy mildew damages leaves, stems and inflorescences, and then reduces the yield and quality of cucumber. This review summarized the research advances in cucumber downy mildew, including pathogen detection and defense pathways, regulatory factors, mining of pathogens-resistant candidate genes, proteomic and genomic analysis, and development of QTL remarks. This review may facilitate clarifying the resistance mechanisms of cucumber to downy mildew.

Biochar addition for enhanced cucumber fruit quality under deficit irrigation / Adição de biochar para melhorar a qualidade de frutos do pepino sob irrigação em déficit

In the recent years, biochar has been used as an organic soil amendment. Therefore, this study was undertaken in April 2016 to July 2017 to examine the effect of different biochar addition (BA) rates and deficit irrigation (DI) on quality characteristics of cucumber under greenhouse conditions over two consecutive growing seasons. The BA treatments were B0 (0-ton ha-1), B1 (10-ton ha-1and B2 (20-ton ha-1), while the DI treatments were 1.0 (W1), 0.60 (W2) and 0.40 (W3) of the reference evapotranspiration (ET0). The results obtained elaborated that the combination of B2W1 gave the maximum values of fruit weight (g), fruit water content (%), fruit dry biomass (g) and pH in the both seasons. On the other hand, W2 and W3 increased significantly titratable acidity (TA %) and total soluble solid (TSS %). It was possible to conclude that BA with DI might be a novel approach to improve both crop yield and fruit quality.

Nos últimos anos, o biochar tem sido utilizado como uma alteração do solo orgânico. Desta maneira, este estudo foi realizado entre os períodos de Abril de 2016 a Julho de 2017 para investigar o efeito de diferentes taxas de alteração de biochar e irrigação por déficit (DI) nas características de qualidade do pepino em casa de vegetação durante duas safras consecutivas. Os tratamentos BA foram B0 (0 ton ha-1), B1 (10 ton ha-1 e B2 (20 ton ha-1), juntamente com três lâminas de irrigação em déficit W1, W2 e W3 correspondentes 100%, 60% e 40% da ET0, respectivamente. Os resultados obtidos mostraram que a combinação de B2W1 forneceu os valores máximos de peso dos frutos (g), teor de água dos frutos (%), biomassa seca dos frutos (g) e pH nas duas safras. Por outro lado, W2 e W3 aumentaram significativamente a acidez titulável (TA%) e o sólido solúvel total (TSS%). Foi possível concluir que a alteração de biochar com DI pode ser uma nova abordagem para melhorar tanto a produtividade como a qualidade dos frutos.

Advances in Agrobacterium tumefaciens-mediated transgenic cucumber / 生物工程学报

Cucumber (Cucumis sativus) is an important vegetable crop in the world. Agrobacterium-mediated transgenic technology is an important way to study plant gene functions and improve varieties. In order to further accelerate the transgenic research and breeding process of cucumber, we described the progress and problems of Agrobacterium tumefaciens-mediated transgenic cucumber, from the influencing factors of cucumber regeneration ability, genetic transformation conditions and various additives in the process. We prospected for improving the genetic transformation efficiency and safety selection markers of cucumber, and hoped to provide reference for the research of cucumber resistance breeding and quality improvement.

Influence of physiological and health quality on the vigor of cucumber seeds / Influência da qualidade fisiológica e sanitária no vigor de sementes de pepino

The physiological performance of seeds is related to their physiological quality and seed vigor, while their health quality may interfere with germination and early seedling establishment in the field due to the interaction of microorganisms associated with seeds. The study aimed to evaluate the physiological performance and health quality of cucumber seeds and to verify the relationship between these attributes. The physiological quality of cucumber seeds was evaluated by standard germination tests, first count of germination, controlled deterioration test, electrical conductivity test, seedling emergence, emergence speed index, and traditional accelerated aging and aging modified with saline for 48, 72, and 96 h. The health quality of cucumber seed lots was evaluated by blotter test. Stratification of cucumber seed lots by seedling emergence was similar to seedling emergence by controlled deterioration test, first count of germination, and electrical conductivity results. The cucumber seed lots evaluated showed high germination rates; however, lots 1 and 3 had a better performance in vigor tests than lots 2 and 4. Fungi detected in the blotter test were Alternaria sp., Aspergillus sp., Cladosporium sp., and Penicillium sp. Seed lots 2 and 4 had low vigor evaluated by seedling emergence and controlled deterioration, and showed a higher incidence of Penicillium sp. in the evaluation of health quality of seeds. The incidence of Penicillium sp. may negatively affect the vigor of cucumber seeds evaluated by seedling emergence and by controlled deterioration test.(AU)

O desempenho fisiológico de sementes diz respeito à sua qualidade fisiológica e vigor, enquanto a qualidade sanitária pode interferir na germinação e estabelecimento inicial de plântulas no campo devido à interação dos micro-organismos associados às sementes. O trabalho teve por objetivo avaliar o desempenho fisiológico e a qualidade sanitária de sementes de pepino e verificar a relação entre esses atributos. A qualidade fisiológica de sementes de pepino foi avaliada pelos testes de germinação, primeira contagem de germinação, deterioração controlada, condutividade elétrica, emergência de plântulas, índice de velocidade de emergência e envelhecimento acelerado tradicional e modificado com solução salina por 48, 72 e 96 horas. A qualidade sanitária das sementes foi avaliada pelo método do papel-filtro. A estratificação de lotes de sementes de pepino ocorreu de maneira similar à emergência de plântulas pelos testes de deterioração controlada, primeira contagem da germinação e condutividade elétrica. Os lotes de sementes de pepino avaliados apresentaram alto percentual de germinação; no entanto, os lotes 1 e 3 apresentaram melhor desempenho nos testes de vigor que os lotes 2 e 4. Os fungos detectados no teste do papel-filtro foram Alternaria sp., Aspergillus sp., Cladosporium sp. e Penicillium sp. Os lotes 2 e 4 de menor vigor avaliados pelos testes de emergência de plântulas e de deterioração controlada foram os mesmos que apresentaram maior incidência de Penicillium sp. na avaliação da qualidade sanitária das sementes. A incidência de Penicillium sp. pode influenciar negativamente o vigor de sementes de pepino avaliado pela emergência de plântulas pelo teste de deterioração controlada.(AU)

Growth kinetics of Escherichia coli O157: H7 on the epicarp of fresh vegetables and fruits

ABSTRACT Despite the increasing reports on the incidence of fresh vegetables and fruits as a possible vehicle for human pathogens, there is currently limited knowledge on the growth potential of Escherichia coli O157:H7 on different plant substrates. This study analyzed the selective adhesion and growth of E. coli O157:H7 on chili habanero (Capsicum chinense L.), cucumber (Cucumis sativus), radish (Raphanus sativus), tomato (Lycopersicon esculentum), beet (Beta vulgaris subsp. vulgaris), and onion (Allium cepa L.) under laboratory conditions. The Gompertz parameters were used to determine the growth kinetics. Scanning electron microscopy was used to visualize the adhesion of E. coli O157:H7 on the epicarp of the samples. Predictive models were constructed to compare the growth of E. coli O157:H7 on the samples with different intrinsic factors and to demonstrate the low selectivity of the pathogen. No significant difference was observed in the lag-phase duration (LPD), generation time (GT), and exponential growth rate (EGR) of the pathogen adhered to the samples. The interaction between the microorganism and the substrate was less supportive to the growth of E. coli O157:H7 for onion, whereas for tomato and cucumber, the time for the microorganism to attain the maximum growth rate (M) was significantly longer than that recorded for other samples.

Avaliação da qualidade de pepinos em conserva / Evaluation of the quality of canned cucumbers

O trabalho teve como objetivo avaliar as características físicas, as físico-químicas e a rotulagemde 11 marcas de pepinos em conserva comercializados no município de Itaqui, RS. Foramrealizadas a contagem do número de pepinos nos recipientes, a determinação do diâmetro edo comprimento dos pepinos, peso bruto, peso líquido, peso drenado, espaço livre, vácuo, pH,acidez total titulável e cloretos. Os rótulos das amostras de pepinos em conserva avaliadosobedeceram às normas de rotulagem geral de acordo com a legislação. Os valores de peso líquido edrenado foram superiores aos especificados pelos fabricantes. O espaço livre no frasco continentevariou de 0,83 a 2,23 cm e o vácuo apresentou valores entre 2,67 e 8,33 pol. Hg. A acidez totaltitulável apresentou valores entre 0,48 e 0,92 g de ácido acético/100 g. O pH em todas as amostrasfoi menor do que 4,5. Os teores de cloretos variaram de 1,70 a 3,47 g de cloreto de sódio/100 g.Pode-se afirmar que os pepinos em conserva avaliados são seguros, pois apresentaram pH menorque 4,5. No entanto, as marcas comercializadas não apresentaram padrão para as demais variáveis,pois foram encontradas diferenças nesses parâmetros avaliados.

The objective of this study was to evaluate the physical, the physical-chemical characteristicsand the labeling of 11 brands of canned cucumbers commercialized in the municipality ofItaqui, RS. The cucumbers quantity, diameter, length, gross weight, net weight, drainedweight, free space, vacuum, pH, total titratable acidity and chlorides were determined. All of theevaluated canned cucumber labels complied with the general labeling standards in accordancewith the legislation. The values of liquid weight and drained weight were higher than thosestated by the manufacturers. The free space in the container ranged from 0.83 to 2.23 cm, andthe vacuum values were from 2.67 to 8.33 in pol. Hg. The titratable total acidity presented valuesfrom 0.48 to 0.92 g of acetic acid/100 g. The pH for all of the samples was less than 4.5. Thechloride contents (g sodium chloride/100 g) ranged from 1.70 to 3.47. It can be stated thatthe evaluated canned cucumbers are safe, since they presented pH lower than 4.5. However,the commercial brands did not show the standard for the other variables, as differences werefound in these evaluated parameters.

Avaliação da qualidade de pepinos em conserva / Evaluation of the quality of canned cucumbers

O trabalho teve como objetivo avaliar as características físicas, as físico-químicas e a rotulagem de 11 marcas de pepinos em conserva comercializados no município de Itaqui, RS. Foram realizadas a contagem do número de pepinos nos recipientes, a determinação do diâmetro e do comprimento dos pepinos, peso bruto, peso líquido, peso drenado, espaço livre, vácuo, pH, acidez total titulável e cloretos. Os rótulos das amostras de pepinos em conserva avaliados obedeceram às normas de rotulagem geral de acordo com a legislação. Os valores de peso líquido e drenado foram superiores aos especificados pelos fabricantes. O espaço livre no frasco continente variou de 0,83 a 2,23 cm e o vácuo apresentou valores entre 2,67 e 8,33 pol. Hg. A acidez total titulável apresentou valores entre 0,48 e 0,92 g de ácido acético/100 g. O pH em todas as amostras foi menor do que 4,5. Os teores de cloretos variaram de 1,70 a 3,47 g de cloreto de sódio/100 g. Pode-se afirmar que os pepinos em conserva avaliados são seguros, pois apresentaram pH menor que 4,5. No entanto, as marcas comercializadas não apresentaram padrão para as demais variáveis, pois foram encontradas diferenças nesses parâmetros avaliados.

The objective of this study was to evaluate the physical, the physical-chemical characteristics and the labeling of 11 brands of canned cucumbers commercialized in the municipality of Itaqui, RS. The cucumbers quantity, diameter, length, gross weight, net weight, drained weight, free space, vacuum, pH, total titratable acidity and chlorides were determined. All of the evaluated canned cucumber labels complied with the general labeling standards in accordance with the legislation. The values of liquid weight and drained weight were higher than those stated by the manufacturers. The free space in the container ranged from 0.83 to 2.23 cm, and the vacuum values were from 2.67 to 8.33 in pol. Hg. The titratable total acidity presented values from 0.48 to 0.92 g of acetic acid/100 g. The pH for all of the samples was less than 4.5. The chloride contents (g sodium chloride/100 g) ranged from 1.70 to 3.47. It can be stated that the evaluated canned cucumbers are safe, since they presented pH lower than 4.5. However,the commercial brands did not show the standard for the other variables, as differences were found in these evaluated parameters.

Antioxidative enzymes of Cucumis sativus seeds are modulated by Leucaena leucocephala extracts / Enzimas antioxidativas de sementes de Cucumis sativus são moduladas por extratos de Leucaena leucocephala

This study aimed to analyze oxidative stress produced in cucumber seeds and seedlings when exposed to aqueous extract from dried leaves of leucaena, as well as its effect on the germination behavior, early growth and the antioxidant enzymes activity. It was evaluated the percentage, the speed index, the average time, the frequency and germination synchronization, the root length and shoot, as well as the catalase and peroxidase enzymes activity. There was no significant inhibitory effect of the leaf extracts on the germination percentage. However, there was delay in the seeds germination, as the extract proportion increased. A stimulatory effect of the extract compared to the shoot length was observed, however the root growth was significantly reduced. The catalase activities had a peak at 24 hours after soaking the seeds, however, the activities were reduced in seedlings. The peroxidase activity was low in the seeds and increased in the seedlings at 168 hours after immersion. The results suggest that there was oxidative stress due to allelochemicals present in the leaves extracts from leucaena, verified by germination and initial growth changes, causing alterations in the plants rootlets.

Este trabalho objetivou analisar o estresse oxidativo produzido em sementes e plântulas de pepino quando submetidas a extrato aquoso de folhas secas de leucena bem como, seu efeito sobre o comportamento germinativo, crescimento inicial e atividade de enzimas antioxidantes. Foram avaliadas a porcentagem, índice de velocidade, tempo médio, frequência e sincronização da germinação, comprimento de raiz e parte aérea e atividade das enzimas catalase e peroxidase. Não houve efeito inibitório significativo dos extratos sobre a porcentagem de germinação. No entanto, houve atraso na germinação das sementes, à medida que se aumentou a proporção do extrato. Foi observado efeito estimulatório do extrato em relação ao comprimento da parte aérea, porém o crescimento da raiz foi reduzido significativamente. As atividades da catalase tiveram pico às 24 horas de embebição das sementes, tendo sido reduzido nas plântulas. No entanto, a atividade da peroxidase foi baixa nas sementes e teve aumento nas plântulas, às 168 horas após a embebição. Os resultados sugerem que houve estresse oxidativo devido aos aleloquímicos presentes nos extratos foliares de leucena, verificado pelas alterações na germinação e de crescimento inicial, o que causou alterações nas radículas das plântulas.

Measurement of expansin activity and plant cell wall creep by using a commercial texture analyzer

Background: Expansins play an important role in cell wall metabolism and fruit softening. Determination of expansin activity is a challenging problem since it depends on measuring cell wall properties by using ad hoc extensometers, a fact that has strongly restricted its study. Then, the objective of the work was to adapt a methodology to measure cell wall creep and expansin activity using a commercial texture meter, equipped with miniature tensile grips and an ad hoc cuvette of easy construction. Results: It was possible to measure hypocotyls acid growth and expansin activity in a reliable and reproducible way, using a commercial texture meter, common equipment found in laboratories of food science or postharvest technology. Expansin activity was detected in protein extracts from cucumber hypocotyls, tomato and strawberry fruits, and statistical differences in expansin activity were found in both fruit models at different ripening stages. Conclusions: The possibility of measuring expansin activity following this adapted protocol with a commercial texture meter could contribute to ease and increase the analysis of expansin in different systems, leading to a better understanding of the properties of these proteins under different experimental conditions.

Exogenous glutathione reduces the damage induced by cadmium in cucumber seedlings / Glutationa exógena reduz o dano induzido por cadmio em plantulas de pepino

Cadmium (Cd) toxicity is a worldwide problem for crop production. The present work used hydroponic experiments to investigate the ameliorating effects and physiological mechanisms of glutathione (GSH) mitigation of Cd toxicity in cucumber seedlings. The results revealed that Cd was mainly accumulated in roots of cucumber, 100 µM GSH pretreatment in 50 µM Cd solution significantly recovered Cd-induced growth inhibition, improved photosynthetic and chlorophyll fluorescence performance. Moreover, external GSH obviously depressed hydroxyl free radical (·OH) and malondialdehyde accumulation, increased the total antioxidant capacity in cucumber exposed to Cd. Results indicated that pre-treatment of GSH can alleviate Cd toxicity by reducing Cd uptake and ROS accumulation, reduce the negative consequences of oxidative stress caused by Cd toxicity, moreover protect photosynthetic machinery from damaging, balance nutrients and antioxidants in cucumber.

A toxicidade do Cádmio (Cd) é um problema mundial para a produção de plantas olerícolas. O presente trabalho com o uso experimentos hidropônicos objetivou investigar a atenuação dos efeitos do cádmio por meio de mecanismos envolvendo a glutationa (GSH) e redução da toxicidade em plântulas de pepino submetidas ao Cd. OS resultados revelaram que o Cd acumulou principalmente nas raízes do pepino, Na dose de 100 µM GSH-50 esta reduziu a concentração em µM Cd na solução ea mesma melhora a ou reduz a inibição do crescimento ,bem como melhora o desempenho e a fluorescência clorofílica. Além disso, obviamente, radical Livre hidroxila GSH externa ·OH) aumenta a acumulação do malondialdeído e aumento da capacidade antioxidante total no pepino expostos ao Cd. OS resultados indicaram que o pré -tratamento de GSH pode reduzir a toxicidade, reduzindo a captação Cd e acumulação ROS , reduzir os efeitos negativos do stress oxidativo reduzindo a sua toxicidade, além de proteger o equilíbrio da disponibilidade de nutrientes e antioxidantes.

Phylogenetic and Bioinformatics Analysis of Replicase Gene Sequence of Cucumber Green Mottle Mosaic Virus / 病毒学报

The replicase genes of five isolates of Cucumber green mottle mosaic virus from Jiangsu, Zhejiang, Hunan and Beijing were amplificated, sequenced and analyzed. The similarities of nucleotide acid sequences indicated that 129 kD and 57 kD replicase genes of CGMMV-No. 1, CGMMV-No. 2, CGMMV-No. 3, CGMMV-No. 4 and CGMMV-No. 5 were 99.64% and 99.74%, respectively. The similarities of 129 kD and 57 kD replicase genes of CGMMV-No. 1, CGMMV-No. 3 and CGMMV-No. 4 were 99.95% and 99.94%, while they were lower between CGMMV-No. 2 and the rest of four reference sequences, just from 99.16% to 99.27% and from 99.04% to 99.18%. All reference sequences could be divided into six groups in neighbor-joining (NJ) phylogenetic trees based on the replicase gene sequences of 129 kD, 57 kD protein respectively. CGMMV-No. 1, CGMMV-No. 3 and CGMMV-No. 4 were clustered together with Shandong isolate (Accession No. KJ754195) in two NJ trees; CGMMV-No. 5 was clustered together with Liaoning isolate (Accession No. EF611826) in two NJ trees; CGMMV-No. 2 was clustered together with Korea watermelon isolate (Accession No. AF417242) in phylogenetic tree of 129 kD replicase gene of CGMMV; Interestingly, CGMMV-No. 2 was classified as a independent group in phylogenetic tree of 57 kD replicase gene of CGMMV. There were no significant hydrophobic and highly coiled coil regions on 129 kD and 57 kD proteins of tested CGMMV isolates. Except 129 kD protein of CGMMV-No. 4, the rest were unstable protein. The number of transmembrane helical segments (TMHs) of 129 kD protein of CGMMV-No. 1, CGMMV-No. 2, CGMMV-No. 3 and CGMMV-No. 5 were 6, 6, 2 and 4, respectively, which were 13, 13 and 5 on the 57 kD protein of CGMMV-No. 2, CGMMV-No. 4 and CGMMV-No. 5. The glycosylation site of 129 kD protein of tested CGMMV isolates were 2, 4, 4, 4 and 4, and that of 57 kD protein were 2, 5, 2, 5 and 2. There were difference between the disorders, globulins, phosphorylation sites and B cell antigen epitopes of 129 kD and 57 kD proteins of tested CGMMV isolates. The current results that there was no significant difference between the replicase gene sequences, it was stable and conservative for intra-species and clearly difference for inter-species. CGMMV-No. 1, CGMMV-No. 3, CGMMV-No. 4 and CGMMV-No. 5 had. a close genetic relationship with Shandong and Liangning isolates (Accession No. KJ754195 and EF611826), they are potentially originate from the same source. CGMMV-No. 2 was closer with Korea isolate. High sequence similarity of tested samples were gathered for a class in phylogenetic tree. It didn't show regularity of the bioinformatics analysis results of 129 kD and 57 kD proteins of tested CGMMV isolates. There was no corresponding relationship among the molecular phylogeny and the bioinformatics analysis of the tested CGMMV isolates.

Composição química e atividade alelopática do óleo essencial de eucalipto / Chemical composition and allelopathic activity of the eucalyptus essential oil

Os óleos essenciais constituem um tipo de metabólito secundário de grande importância econômica e estão sendo cada vez mais estudados e utilizados como potentes inibidores de sementes e do crescimento de diversas plantas. O presente trabalho teve por objetivo a análise química qualitativa e quantitativa bem como a avaliação da atividade alelopática do óleo essencial extraído das folhas frescas de eucalipto (Eucalyptus citriodora) sobre a germinação e o desenvolvimento radicular das sementes de sorgo (Sorghum bicolor L.) e pepino (Cucumis sativus L.), cultivados em placa de Petri. O óleo essencial foi obtido por hidrodestilação, utilizando um aparelho tipo Clevenger, e analisado por cromatografia em fase gasosa com detector de ionização de chama e espectrometria de massas. Foi possível identificar doze constituintes químicos correspondendo a 97,69%, com predominância dos monoterpenos oxigenados citronelal (64,92%) e iso-isopulegol (10,20%) e do citronelol (8,25%). Os ensaios biológicos utilizando o óleo essencial mostraram que o mesmo apresenta efeito alelopático, prejudicando a germinação e o desenvolvimento da radícula das sementes de sorgo e pepino, sendo a redução da germinação mais pronunciada no sorgo, e que o aumento da concentração do óleo leva a uma redução linear na capacidade germinativa e no desenvolvimento da radícula.

Essential oils consist of a type of secondary metabolite that holds great economic importance, they have been increasingly studied and used as potent inhibitors of seeds and growth of various plants. The present work aimed at the qualitative and quantitative chemical analysis and evaluation of the allelopathic activity of the essential oil extracted from fresh leaves of eucalyptus (Eucalyptus citriodora) over the germination and root development of seeds of sorghum (Sorghum bicolor L.) and cucumber (Cucumis sativus L.), grown in a Petri dish. The essential oil was obtained by steam distillation, using a Clevenger apparatus, and analyzed by chromatography in gas phase with flame ionization detector and mass spectrometry. It was possible to identify twelve chemical constituents corresponding to 97.69%, with predominance of oxygenated monoterpenes citronellal (64.92%) and iso-isopulegol (10.20%) and citronellol (8.25%). The biological essays using the essential oil showed the presence of an allelopathic effect, affecting the germination and radicule length of sorghum and cucumber seeds, the germination reduction being more pronounced in sorghum, also the increase of the oil concentration leads to a linear decrease in the germination and in the radicule length.

Chemical constituents contained in fatty oil from seeds of Cucumis sativus / 中国中药杂志

<p><b>OBJECTIVE</b>To study the chemical constituents contained in the seeds of Cucumis sativus.</p><p><b>METHOD</b>The fatty oil was extracted by heating and refluxing with petroleum ether. Potassium hydroxide-methanol solution was used for saponification. An unsaponifiable matter was extracted by EtOAc and separated with various chromatographic methods. Its structure was identified on the basis of their physicochemical properties and spectral data. The fatty acid fraction was methyl-esterified and determined by GC. The composition and relative content of fatty acid were determined with normalization method of peak area.</p><p><b>RESULT</b>24-ethylcholesta-7, 22, 25-trienol (1), 24-ethylcholesta-7, 25-dienol (2) ,avenasterol (3), spinasterol (4), karounidiol (5) and isokarounidiol (6) were separated and identified from the unsaponifiable matter. Myristic acid (7, 0.12%), palmitic acid (8, 12.04%), palmitoleic acid (9, 0.09%), heptadecanoic acid (10, 0.06%), stearic acid (11, 5.64%), oleic acid (12, 6.95%), linoleic acid (13, 74.40%), arachidic acid (14, 0.19%), and alpha-linolenic acid (15, 0.51%) were identified from the fatty acids part.</p><p><b>CONCLUSION</b>Compounds 5, 6, 9, 10, 14,and 15 were first reported in C. sativus.</p>

Dinámica de impregnación al vacío en apio (Apium graveolens L) y pepino (Cucumis sativus L) / Vacuum impregnation dynamic on celery (Apium graveolens L) and cucumber (Cucumis sativus L)

Objetivo. Evaluar la respuesta a la impregnación al vacio (IV) en apio y pepino, con soluciones isotónicas de NaCl. Materiales y métodos. Se determinaron variables de impregnación en troncos de apio y rodajas de pepino (3 posiciones diferentes a lo largo de su estructura), considerando, fracción y deformación volumétrica en la etapa de vacío (X1 y g1) y atmosférica (X y g), y la porosidad disponible (Ee) al proceso IV. Resultados. El apio y pepino no presentaron diferencias estadísticas por efecto de la posición. En las etapas de proceso se obtuvieron para el apio y el pepino valores de X1 (-14.32 ± 2.75 y -5.51±1.76%, g1 (-0.587±0.69 y -0.079±0.99%), X(13.49±2.32 y 6.72±2.72%), g (-1.40±1.042% y -2.33±1.26%) y Ee (15.73±2.31 y 9.35±2.57%), respectivamente. Estos resultados indicaron una salida de líquido nativo (X1<0) y una ligera contracción volumétrica de las estructuras (g y g1<0), lo cual se evidenció microestructuralmente. Conclusiones. La respuesta a la IV en apio y pepino, permite identificar estas matrices alimentarias, como aptas para la incorporación de componentes que le proporcionen un valor agregado a estos productos.

Economic analysis of cucumber and lettuce intercropping under greenhouse in the winter-spring

The economical analysis complements the evaluation of the intercrop systems efficiency, considering besides the physical production of crops, the price of products according to their quality classification and time of the year. Intercropping systems of lettuce and cucumber in two plant populations under greenhouse were economically evaluated in winter-spring, in Jaboticabal City, São Paulo State, Brazil. The total operating cost (TOC) of cucumber and lettuce as sole crop and intercropping were estimated, as well as gross revenue (GR) and operating profit (OP). The labor for the crops was the component with greater participation in the TOC of crops in intercropping and single crop. Greater GR and OP were observed in intercrops established by transplanting lettuce and cucumbers on the same day. Considering the operating profit and the land efficient ratio, it is recommended the intercropping of lettuce transplanted until 10 days after the transplanting (DAT) of cucumber with two rows per plot, and at 0 DAT of cucumber grown with a row plot.

A análise econômica complementa a avaliação da eficiência dos cultivos consorciados, considerando além da produção física das culturas, o preço dos produtos segundo sua classificação qualitativa e época do ano. Avaliou-se economicamente consórcios de alface crespa e pepino, em duas populações de plantas, no inverno-primavera, em casa de vegetação, em Jaboticabal, SP, Brasil. Foram calculados o custo operacional total (COT), a receita bruta (RB) e o lucro operacional (LO) das culturas do pepino e alface em monocultura e em consórcio. A mão-de-obra foi a componente com maior participação no COT das culturas em consórcio e monocultura. Maiores RB e LO foram observadas nos cultivos consorciados estabelecidos com o transplante da alface e do pepino no mesmo dia, independente da densidade populacional. Considerando-se o lucro operacional e o índice de uso eficiente da área, recomenda-se o cultivo consorciado com transplante da alface até 10 dias após o transplante (DAT) do pepino, com duas linhas, e ao 0 DAT do pepino cultivado com uma linha no canteiro.

Diversity analysis of archaeal and fungal communities in adjacent cucumber root soil samples in greenhouse by small-subunit rRNA gene cloning / 生物工程学报

Soil archaea and fungi play important roles in the greenhouse soil ecosystem. To develop and apply rich microbial resources in greenhouse ecological environment, and to understand the interaction between microbes and plants, we constructed archaeal 16S rRNA and fungal 18S rRNA gene libraries to analyze the compositions of archaeal and fungal communities. Total greenhouse soil DNA was directly extracted and purified by skiving-thawing-lysozyme-proteinase K-SDS hot treatment and treatment of cetyltriethylammnonium bromide (CTAB). After PCR amplification, retrieving, ligating, transforming, screening of white clones, archaeal 16S rRNA and fungal 18S rRNA gene libraries were constructed. The sequences of archaea and fungi were defined into operational taxonomic units (OTUs) when 97% similarity threshold for OTU assignment was performed by using the software DOTUR. Phylogenetic analysis showed that crenarchaeota and unidentified-archaea were the two major sub-groups and only a few of euryarchaeota existed in the archaeal clone library, total 45 OTUs. All the crenarchaeota belonged to thermoprotei; except for Basidiomycotina, the other four sub-group fungi were discovered in the fungal library, total 24 OTUs. The diversities of archaea were very abundant and a few euryarchaeota (methanebacteria) existed in the archaeal clone library, it might be directly related to the long-term high temperature, high humidity, and high content of organic matter. The limitation of oxygen was the other reason for causing this phenomenon; Ascomycotina (over 80%) was the dominant sub-groups in fungal library. It was because most of the plant fungal diseases belonged to soil-borne diseases which gone through the winter by the ways of scierotium or perithecium and became the sources of primary infection.

Genome-wide identification and phylogenetic analysis of the ERF gene family in cucumbers

Members of the ERF transcription-factor family participate in a number of biological processes, viz., responses to hormones, adaptation to biotic and abiotic stress, metabolism regulation, beneficial symbiotic interactions, cell differentiation and developmental processes. So far, no tissue-expression profile of any cucumber ERF protein has been reported in detail. Recent completion of the cucumber full-genome sequence has come to facilitate, not only genome-wide analysis of ERF family members in cucumbers themselves, but also a comparative analysis with those in Arabidopsis and rice. In this study, 103 hypothetical ERF family genes in the cucumber genome were identified, phylogenetic analysis indicating their classification into 10 groups, designated I to X. Motif analysis further indicated that most of the conserved motifs outside the AP2/ERF domain, are selectively distributed among the specific clades in the phylogenetic tree. From chromosomal localization and genome distribution analysis, it appears that tandem-duplication may have contributed to CsERF gene expansion. Intron/exon structure analysis indicated that a few CsERFs still conserved the former intron-position patterns existent in the common ancestor of monocots and eudicots. Expression analysis revealed the widespread distribution of the cucumber ERF gene family within plant tissues, thereby implying the probability of their performing various roles therein. Furthermore, members of some groups presented mutually similar expression patterns that might be related to their phylogenetic groups.

Inhibition Effects of Silver Nanoparticles against Powdery Mildews on Cucumber and Pumpkin

Powdery mildew is one of the most devastating diseases in cucurbits. Crop yield can decline as the disease severity increases. In this study, we evaluated the effect of silver nanoparticles against powdery mildew under different cultivation conditions in vitro and in vivo . Silver nanoparticles (WA-CV-WA13B) at various concentrations were applied before and after disease outbreak in plants to determine antifungal activities. In the field tests, the application of 100 ppm silver nanoparticles showed the highest inhibition rate for both before and after the outbreak of disease on cucumbers and pumpkins. Also, the application of 100 ppm silver nanoparticles showed maximum inhibition for the growth of fungal hyphae and conidial germination in in vivo tests. Scanning electron microscope results indicated that the silver nanoparticles caused detrimental effects on both mycelial growth and conidial germination.