Loading...
8 results
Search Results
Now showing 1 - 8 of 8
- Identification and characterization of molecular factors associated with the Phytophthora cinnamomi infection mechanismsPublication . Choupina, Altino; Meirinho, Sofia G.; Carvalho, Marisa; Jorge, Lurdes; Sousa, Maria João; Cravador, Alfredo
- Effects of wild plant essential oils in the growth control of Phytophthora cinnamomi abd the host Castanea sativa MillPublication . Guimarães, Rafaela; Sousa, Maria João; Choupina, Altino; Martins, AnabelaPlant diseases caused by this genus are difficult to control chemically, and the perspective of a active natural product agent as a great importance especially in regions that have chestnut as main natural resource. The essential oils are natural compounds with bactericide, fungicide and allelopathic effects, this characteristics can be a very interesting tool to fifth or control the infections produced by Phytophthora cinnamomi. Essential oils from wild plants growing in the northeast region of Portugal were tested in vitro in is effects on the growth of Phytophthora cinnamomi.The essential oils were tested in differents concentrations from 100% to 2%. Dilutions were madewith alcohol 10%, and were tested in mycelium after 1,2,3, and 4 weeks in culture. Simultaneously in vitro chestnut plants were tested in they growth in the present of imbibed paper filter with the same essential oils and concentrations in order to understand if the essential oils can affect the development of the plants.Preliminary show that essential oils from plants of Mentha genus can reduce the P. cinnamomi growing without affect drastically the C. sativa in vitro development.
- Identification and characterization of molecular factors associated with the Phytophthora cinnamomi infection mechanismsPublication . Choupina, Altino; Meirinho, Sofia G.; Carvalho, Marisa; Jorge, Lurdes; Sousa, Maria João; Cravador, Alfredo
- Silencing the gip gene of Phytophthora cinnamomi by iRNA and subcellular localization of GIP and NPP1 proteinsPublication . Chahed, Abdessalem; Chatti, Noureddine; Costa, Rodrigo Arthur Fonseca; Sousa, Maria João; Choupina, AltinoInk Disease is considered one of the most important causes of the decline of chestnut orchards. The break in yield of Castanea sativa Mill is mainly caused by Phytophthora cinnamomi one of the most aggressive and widespread plant pathogen causing enormous economic losses and up to now no efficient treatments are available to fight these pathogens. Because of the importance of chestnut at economical and ecological levels especially in Portugal, it becomes essential to explore the molecular mechanisms that determine the interaction between Phytophthora species and host plants through the study of proteins GIP and NPP1 produced by P.cinnamomi during the infection.
- Expression analysis by RT-PCR of GIP gene from Phytophthora cinnamomiPublication . Belo, Hélio; Martins, Fátima; Jorge, Lurdes; Sousa, Maria João; Rodrigues, Luciano; Choupina, AltinoSpecies of the genus Phytophthora secrete glucanase inhibitor proteins (GIPs) to inhibit the activity of enzymes involved in plant defense responses, including during plant infection process of Castanea sativa Mill by Phytophthora cinnamomi. GIPs show structural homology to the chymotrypsin class of serine proteases (SP) but lack proteolytic activity due to the absence of an intact catalytic triad and, thus, belong to a broader class of proteins called serine protease homologs (SPH) nonfunctional because one or more residues of the essential catalytic triad is absent (His-Asp-Ser). GIPs show high homology to the S1A subfamily of SP, however questions remain about the expression patterns and potential roles of different GIPs during pathogenesis and their possible interaction with host EGases in the plant apoplast. ORF of GIP gene from P. cinnamomi encodes a 269 aa protein. In order to understand its function, we proceeded to the heterologous expression in Pichia pastoris. The expression was studied during growth in different carbon sources and a time course of glucanase inhibitor protein production by RT-PCR was also performed. The major expression levels occurred at the medium with glucose as carbon source.
- Effects of wild plants essential oils on the growth of Phytophthra cinnamomi and Castanea sativaPublication . Sousa, Maria João; Martins, Fátima; Belo, Hélio; Choupina, Altino; Martins, AnabelaWild plant essential oil effects on the growth control of Phytophthora cinnamomi and Castanea sativa M. João Sousa1, Fátima Martins1, Hélio Belo1, Altino Choupina1, 2 and Anabela Martins1 1Instituto Politécnico de Bragança, Escola Superior Agrária, Campus de Santa Apolónia, Apartado 1172, 5301-854 Bragança, Portugal 2CIMO- Centro de Investigação de Montanha, Campus de Santa Apolónia, Apartado 1172, 5301-854 Bragança, Portugal Corresponding author: joaos@ipb.pt In regions that have chestnut as the main economic resource such as in Bragança, a region in the North of Portugal, plant diseases caused by Phytophthora cinnamomi namely the chestnut ink disease are the reason for major economic losses. The prospect of an active natural product agent has a great importance, especially if this product comes from a spontaneous plant, common in this region. The essential oils are natural compounds with bactericide, fungicide and allelopathic effects, and these characteristics can be a very interesting tool to control the development of the pathogenic agents and prevent infections cause by P. cinnamomi. The essential oils were tested in different concentrations from 100% to 2% dilutions (in 70% ethanol), on P. cinnamomi mycelium after 1, 2, 3, and 4 weeks of pure culture. Since the pathogen can be found in water and can be transmitted through water, their growth was simultaneously tested in the presence of imbibed paper filter with the same essential oils and concentrations, in liquid medium, in order to understand if the essential oil can affect their development in these conditions. The essential oils from Mentha pulegioides wild plants, growing in the Northeast region of Portugal were tested also in vitro for their effect on the growth of C. sativa, to see if the oils are not toxic to this plant. Preliminary results show that essential oils of Mentha species at concentrations of less than 80% can reduce and even stop the growth of P. cinnamomi, and in concentrations of less than 90% do not affect drastically the development of C. sativa in vitro.
- Knockdown of Phytophthora cinnamomi gip gene by iRNAPublication . Chahed, Abdessalem; Costa, Rodrigo Arthur Fonseca; Sousa, Maria João; Choupina, AltinoInk Disease is considered one of the most important causes of the decline of chestnut orchards. The break in yield of Castanea sativa Mill is mainly caused by Phytophthora cinnamomi one of the most aggressive and widespread plant pathogen causing enormous economic losses and up to now no efficient treatments are available to fight these pathogens. Because of the importance of chestnut at economical and ecological levels especially in Portugal, it becomes essential to explore the molecular mechanisms that determine the interaction between Phytophthora species and host plants through the study of GIP protein produced by P.cinnamomi during the infection.
- Silencing the gip gene of Phytophthora cinnamomi by iRNA and subcellular localization of GIP and NPP1 proteinsPublication . Chahed, Abdessalem; Chatti, Noureddine; Costa, Rodrigo Arthur Fonseca; Sousa, Maria João; Choupina, AltinoInk Disease is considered one of the most important causes of the decline of chestnut orchards. The break-in yield of Castanea sativa Mill is mainly caused by Phytophthora cinnamomi one of the most aggressive and widespread plant pathogen causing enormous economic losses and up to now, no efficient treatments are available to fight these pathogens. Because of the importance of chestnut at economical and ecological levels especially in Portugal, it becomes essential to explore the molecular mechanisms that determine the interaction between Phytophthora species and host plants through the study of proteins GIP and NPP1 produced by P.cinnamomi during the infection.