RESUMO
The red flesh coloration of apples is a result of a biochemical pathway involved in the biosynthesis of anthocyanins and anthocyanidins. Based on apple genome analysis, a high number of regulatory genes, mainly transcription factors such as MYB, which are components of regulatory complex MYB-bHLH-WD40, and several structural genes (PAL, 4CL, CHS, CHI, F3H, DFR, ANS, UFGT) involved in anthocyanin biosynthesis, have been identified. In this study, we investigated novel genes related to the red-flesh apple phenotype. These genes could be deemed molecular markers for the early selection of new apple cultivars. Based on a comparative transcriptome analysis of apples with different fruit-flesh coloration, we successfully identified and characterized ten potential genes from the plant hormone transduction pathway of auxin (GH3); cytokinins (B-ARR); gibberellins (DELLA); abscisic acid (SnRK2 and ABF); brassinosteroids (BRI1, BZR1 and TCH4); jasmonic acid (MYC2); and salicylic acid (NPR1). An analysis of expression profiles was performed in immature and ripe fruits of red-fleshed cultivars. We have uncovered genes mediating the regulation of abscisic acid, salicylic acid, cytokinin, and jasmonic acid signaling and described their role in anthocyanin biosynthesis, accumulation, and degradation. The presented results underline the relationship between genes from the hormone signal transduction pathway and UFGT genes, which are directly responsible for anthocyanin color transformation as well as anthocyanin accumulation during apple-fruit ripening.
Assuntos
Ciclopentanos , Malus , Oxilipinas , Malus/genética , Malus/metabolismo , Frutas/genética , Frutas/metabolismo , Antocianinas/metabolismo , Perfilação da Expressão Gênica/métodos , Transcriptoma , Ácido Abscísico/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/metabolismoRESUMO
Microbiological analyses of lettuce, radish, carrot and beetroot were conducted to determine the effect of production system (organic and conventional) on the microbial quality of vegetables in Poland. During 2010-2014 growing seasons, 600 organic and 372 conventional samples were collected from certified farms. The vegetables were analyzed for aerobic mesophilic bacteria, yeasts and molds, Enterobacteriaceae, coliforms and Escherichia coli according to Polish standards. The farmer's survey was conducted to collect information on farm management practices. The index (from 0 - no risk to 4 - high risk) of potential contamination of the produce by human pathogens, related to fertilization system was developed. The mesophilic bacteria, yeasts and molds, coliforms and Enterobacteriaceae numbers for the radish and carrot were similar for organic and conventional cultivation systems (mesophilic bacteria 7.0â¯log10â¯cfuâ¯g-1 and 6.6â¯log10â¯cfuâ¯g-1; yeasts and molds 5.1 and 4.8; coliforms 1.3 and 1.5; Enterobacteriaceae 2.1 and 2.3 for radish and carrot respectively). Organic lettuce harbored significantly more bacteria than conventional (mesophilic 6.7â¯log10â¯cfuâ¯g-1 and 6.4â¯log10â¯cfuâ¯g-1, coliforms 1.8 and 1.4; Enterobacteriaceae 2.5 and 1.9 for organic and conventional respectively). Organic beetroot contained higher number of yeasts and molds (5.1â¯log10â¯cfuâ¯g-1) and Enterobacteriaceae (2.9â¯log10â¯cfuâ¯g-1) than conventional (4.9 and 2.5â¯log10â¯cfuâ¯g-1). The vegetables from organic farms showed significantly higher load of E. coli (on average 0.42â¯log10â¯cfuâ¯g-1) than conventionally cultivated vegetables (in average 0.05â¯log10â¯cfuâ¯g-1). The index 0-4 of potential risk of produce contamination by human pathogens was created according to fertilization practices in both farm types. Its value increased with enhanced contribution of manures and other animal wastes. In organic production the main fertilization practice was application of animal manures, composted and not composted. A popular practice was also top dressing of growing plants with fermented plant extracts, sometimes enriched with dungwater. In conventional farming system mineral fertilization was the main source of the vegetable nutrition. Therefore, organic produce indicated higher index of contamination risk (2-4) than conventional vegetables (1-2). High indexes were positively associated with higher number of E. coli. It was found that fertilization system practiced in organic farms may deteriorate sanitary quality of the produce.
Assuntos
Carga Bacteriana , Escherichia coli/crescimento & desenvolvimento , Contaminação de Alimentos/análise , Fungos/crescimento & desenvolvimento , Agricultura Orgânica , Verduras/microbiologia , Agricultura , Animais , Beta vulgaris/microbiologia , Contagem de Colônia Microbiana , Daucus carota/microbiologia , Escherichia coli/isolamento & purificação , Fungos/isolamento & purificação , Humanos , Lactuca/microbiologia , Esterco/microbiologia , Polônia , Raphanus/microbiologiaRESUMO
Molecular markers that enable monitoring of fungi in their natural environment or assist in the identification of specific strains would facilitate Trichoderma utilization, particularly as an agricultural biocontrol agent (BCA). In this study, sequence analysis of internal transcribed spacer regions 1 and 2 (ITS1 and ITS2) of the ribosomal RNA (rRNA) gene cluster, a fragment of the translation elongation factor 1-alpha (tef1) gene, and random amplified polymorphic DNA (RAPD) markers were applied to determine the genetic diversity of Trichoderma atroviride strains collected in Poland, and also in order to identify loci and PCR-based molecular markers useful in genetic variation assessment of that fungus. Although tef1 and RAPD analysis showed limited genetic diversity among T. atroviride strains collected in Poland, it was possible to distinguish major groups that clustered most of the analyzed strains. Polymorphic RAPD amplicons were cloned and sequenced, yielding sequences representing 13 T. atroviride loci. Based on these sequences, a set of PCR-based markers specific to T. atroviride was developed and examined. Three cleaved amplified polymorphic sequence (CAPS) markers could assist in distinguishing T. atroviride strains. The genomic regions identified may be useful for further exploration and development of more precise markers suitable for T. atroviride identification and monitoring, especially in environmental samples.
Assuntos
Loci Gênicos , Variação Genética , Trichoderma/classificação , Trichoderma/genética , Análise por Conglomerados , DNA Fúngico/química , DNA Fúngico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Marcadores Genéticos , Dados de Sequência Molecular , Tipagem Molecular , Técnicas de Tipagem Micológica , Fator 1 de Elongação de Peptídeos/genética , Filogenia , Polônia , Técnica de Amplificação ao Acaso de DNA Polimórfico , Análise de Sequência de DNA , Trichoderma/isolamento & purificaçãoRESUMO
Specific bacterial disease symptoms were observed on onion bulbs in almost all regions in Poland. For the purpose of identification of agents causing disease, bacteria were isolated from the symptomatic plants. Their pathogenicity was confirmed by using pathogenicity test on onion scales. These bacteria were identified biochemically and molecularly as Serratia plymuthica.