Coffee genes associated with systemic acquired resistance (SAR) and incompatible reaction against coffee leaf rust inoculation were identified by suppression subtractive hybridization. Analysis of 384 clones of each of the subtracted cDNA libraries identified genes involved in oxidative burst ⁄ apoptosis ⁄ hypersensitive response, synthesis of antimicrobial proteins, synthesis and transport of antimicrobial metabolites, signal perception and transduction, metabolism of lipids, regulated protein degradation and cell maintenance and development. Induction of distinct sets of genes in the two resistance responses was observed. A wide range of genes involved in defence responses described in other plant species was also found in coffee plants. Semi-quantitative and quantitative RT-PCR analysis of seven selected genes showed differences in their expression profile within 72 h after treatment. Fulllength cDNA sequences of two b-1,3-glucanases, one induced during SAR and the other in the incompatible reaction, were obtained by 5¢ and 3¢ RACE and the sequence data suggest different properties and cellular localization of the encoded proteins.
Resumo -O objetivo deste trabalho foi determinar o efeito de 60 isolados de Trichoderma e do produto Trichodermil na promoção do crescimento e na indução de resistência sistêmica à antracnose, causada por Colletotrichum lagenarium em pepineiro, além de identificar as espécies dos isolados de Trichoderma spp. efetivas como indutores de resistência. Nos experimentos de promoção de crescimento, os isolados de Trichoderma spp. foram submetidos à inoculação no substrato e, após 21 dias, a massa de matéria seca da parte aérea das plantas foi mensurada. Nos experimentos de indução de resistência, os isolados que promoveram crescimento foram introduzidos no substrato, na base das plantas, sete dias antes da inoculação de C. lagenarium nas folhas. O isolado que apresentou melhor desempenho foi avaliado quanto à redução dos sintomas de antracnose, em aplicações aos 3, 7 ou 14 dias antes da inoculação do patógeno, e quanto à capacidade de aumentar a atividade de peroxidase. Dezenove isolados e o Trichodermil promoveram o crescimento de pepineiro em até 100% e conferiram proteção à antracnose em até 88,39%. O isolado IB 31/06 reduziu a severidade da doença nos intervalos de tempo avaliados. Não foi observado aumento significativo de peroxidase, sete dias após o tratamento com IB 31/06, nas plantas tratadas e infectadas com o patógeno, em comparação às plantas infectadas. O sequenciamento gênico dos dezenove isolados permitiu a identificação de sete espécies distintas de Trichoderma.Termos para indexação: Colletotrichum lagenarium, Cucumis sativus, antagonismo, biocontrole, indução de proteção sistêmica, peroxidase. Growth promotion and resistance induction against anthracnosein cucumber using Trichoderma spp.Abstract -The objective of this work was to determine the effect of 60 isolates of Trichoderma and the product Trichodermil on the growth promotion and on the induction of systemic resistance to anthracnose caused by Colletotrichum lagenarium in cucumber, and to identify isolates of Trichoderma spp. effective as resistance inductors. In the assays of growth promotion, the Trichoderma spp. isolates were inoculated in the substrate and, after 21 days, the shoot dry weight of the plants was measured. In the experiments of resistance induction, the isolates which promoted growth were inoculated in the substrate, at the base of the plants, seven days before C. lagenarium inoculation in the leaves. The isolate which showed the best performance was evaluated for anthracnose symptom reduction in applications at 3, 7 or 14 days before the pathogen inoculation, and for its ability of increasing the peroxidase activity. Nineteen isolates and Trichodermil promoted cucumber growth up to 100% and conferred plant protection against anthracnose up to 88.39%. The isolate IB 31/06 reduced the disease severity at the evaluated time intervals. No significant peroxidase increase was observed seven days after treatment with IB 31/06, in the plants treated and infected with the pathogen, in comparison to infected plants. Gene sequencing of th...
1,3-glucanase and chitinase activities were induced locally and systemically 4-25 and 11-25 days, respectively, after spraying the surface ofthe third pair of coffee leaves from the apex of 8-month-old plants with a 50 mg/ml aqueous suspension of Bacillus thuringiensis in a commercial formulation (Thuricide HP-Sandoz). The treatment also induced local and systemic resistance against Hemileia vastatrix after the application of the inducer. Within 14-18 days of application of the Thuricide inducer, the ^-1,3-glucanase activity in the locallyand systemically-protected unchallenged leaves reached maximum levels of 226% and 279% higher levels respectively, than in control plants. The chitinase activity reached maximum levels of 224% and 181% respectively, within 18-21 days after treatment with the inducer. Twô -1,3-glucanase bands were detected by native PAGE electrophoresis in extracts from locally-and systemicallyprotected unchallenged coffee leaves. Zusammenfassung Lokale nnd systemische InduktioD von ^-l,M^lucaiiase und chitinase in Kaffeebliittem, die durch Bacillus thuringiensis gegen Hemileia vastatrix geschllut sind Die Oberfiache des von oben gesehenen dritten Blattpaars 8 Monate alter Kaffeepfianzen wurde mit einer waBrigen Bacillus thuringiensisSnsptnsxon (50 mg/ml, im Handel erhaltliches Praparat Thuricide HP-Sandoz) bespriiht. Nach 4-25 Tagen wurden lokale Aktivitaten von jS-l,3-Glucanase und Chitinase, nach 11-25 Tagen systemische Ativitaten dieser Enzyme festgestellt. Die Applikation des Induktors rief zudem eine lokale und systemische Resistenz gegen Hemileia vastatrix hervor. 14-18 Tage nach der Applikation des Thuricide-lnduktors erreichte die jS-l,3-Glucanase-Aktivitat in den lokal bzw. systemisch geschutzen, nicht herausgeforderten Blattern Maximalwerte, die um 226% bzw. 279% hoher lagen als die bei Kontrollpflanzen gemessenen Werte. Die Chitinaseaktivitat erreichte 18-21 Tage nach der Behand-lung mit dem induktor Hochstwerte von 224% bzw. 181 % Durch native Polyamid-Gelelektrophorese (PAGE) wurden zwei /?-l,3-Glucanase-Banden in Extrakten detektiert, die aus lokal und systemisch geschutzten, nicht herausgeforderten Kaffeeblattern stammten.
O objetivo deste trabalho foi avaliar a capacidade de Trichoderma spp. em promover o crescimento de plantas de feijão e reduzir a severidade da antracnose do feijoeiro (Colletotrichum lindemuthianum), bem como identificar os isolados mais eficientes. Sessenta isolados de Trichoderma spp. foram avaliados quanto à capacidade de promoção do crescimento nas plantas. Os sete isolados que mais se destacaram foram adicionados ao substrato de cultivo e avaliados quanto à redução na severidade da antracnose em plantas de feijão tratadas com conídios de C. lindemuthianum. Os mais eficientes no controle da doença foram identificados por sequenciamento de DNA. O isolado IB 28/07 foi avaliado nas concentrações 0,5, 1, 1,5 e 2% (peso:volume), que reduziram a severidade da doença em 41,51, 55,15, 81,82 e 96,06%, respectivamente. Os isolados mais eficientes de Trichoderma spp. podem proporcionar aumentos superiores a 30% na produção de matéria seca da parte aérea das plantas e reduzir a severidade da doença entre 63 e 98%. Esses isolados foram identificados como pertencentes às espécies Trichoderma harzianum, T. strigosum e T. theobromicola.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.