Forest tree species such as Eucalyptus and Pine are subjected to attack by various pests and pathogens during their life-time. Examples are the insect pest, Leptocybe invasa, the stem canker pathogen, Chrysoporthe austroafricana, the root rot pathogen, Phytophthora cinnamomi, and the pitch canker pathogen Fusarium circinatum. Disease incidence is exacerbated by climate change, which is predicted to make environments more favorable for pathogens and pests. "Host-jumping" from native hosts to forest plantations has been reported. Such threats are especially severe for clonally propagated tree species such as Eucalyptus as entire plantations could be lost due to susceptibility of a particular clone. Thus genotypes with improved resistance or tolerance are necessary as part of an integrated management strategy to curb losses due to pests and pathogens. It is with this vision that the Eucalyptus and Pine Pathogen Interactions programme was initiated. The research in our programme is aimed at understanding the plant defence mechanisms that exist in Eucalyptus and Pine trees which may be harnessed to improve its resistance capacity in future. We are currently dissecting the Eucalyptus defensome (or defence transcriptome) based on the recently released genome sequence of Eucalyptus grandis, coupled with data from high-throughput transcriptome technologies.

Collaboration:

  • Tree Pathology Co-operative Programme
  • Sappi and Mondi

On-going projects:

Projects undertaken by EPPI aim to (i) ascertain the molecular basis of disease responses in Eucalyptus to a canker pathogen Chrysoporthe austroafricana (ii) determine the molecular defence mechanisms of E. grandis against the gall wasp Leptocybe invasa and (iii) determine the effectiveness of induced resistance in Pinus patula against Fusarium circinatum. These pathosystems provide the biological platform to address key questions such as: "What is the molecular basis of tolerance and susceptibility?", "What are the signature defence responses to different types of pests and pathogens?", "What are the convergent defence responses in the host?" and "Which regulatory sequences and defence genes could be targeted for enhancing defence in the host?". This would provide a basis to implement biotechnology strategies to develop resistant families (seedling forestry) or clones (clonal forestry) in future.

New Publications

Backer R, Naidoo S, van den Berg N. (2023) The expression of the NPR1-dependent defense response pathway genes in Persea americana (Mill.) following infection with Phytophthora cinnamomi. BMC Plant Biology 23(1):548. 10.1186/s12870-023-04541-z PDF
Swanepoel S, Visser EA, Shuey SS, Naidoo S. (2023) The In Planta Gene Expression of Austropuccinia psidii in Resistant and Susceptible Eucalyptus grandis. Phytopathology 113(6):1066-1076. 10.1094/PHYTO-07-22-0257-R PDF
Solís M, Hammerbacher A, Wingfield MJ, Naidoo S. (2023) A robust disease scoring method to screen Eucalyptus for resistance against the aggressive leaf blight pathogen, Teratosphaeria destructans. Plant Disease:1418 - 1424. 10.1094/PDIS-06-22-1347-RE PDF
Teshome DT, Zharare GE, Ployet R, Naidoo S. (2023) Transcriptional reprogramming during recovery from drought stress in Eucalyptus grandis. Tree Physiology 10.1093/treephys/tpad022
Swanepoel S, Visser E, Shuey L, Naidoo S. (2023) The In Planta Gene Expression of Austropuccinia psidii in Resistant and Susceptible Eucalyptus grandis. PHYTOPATHOLOGY 10.1094/PHYTO-07-22-0257-R
Visser EA, Kampmann TP, Wegrzyn JL, Naidoo S. (2022) Multispecies comparison of host responses to Fusarium circinatum challenge in tropical pines show consistency in resistance mechanisms. Plant, Cell & Environment 46(5):1705-1725. 10.1111/pce.14522 PDF
Solís M, Wingfield MJ, Hammerbacher A, Naidoo S. (2022) Comparison of the infection biology of Teratosphaeria destructans and Teratosphaeria epicoccoides on Eucalyptus. Plant Disease 10.1094/PDIS-09-21-1877-RE PDF
Messal M, Vivas M, Kemler M, Begerow D, Brachmann A, Witfeld F, Naidoo S, Slippers B. (2022) Fungal Communities of Eucalyptus grandis Leaves Are Influenced by the Insect Pest Leptocybe invasa. Frontiers in Microbiology 13(3:841621) 10.3389/fmicb.2022.841621 PDF
Jackson C, Christie N, Reynolds SM, Marais GC, Tii-kuzu Y, Caballero M, Kampman T, Visser EA, Naidoo S, Kain D, Whetten RW, Isik F, Wegrzyn J, Hodge GR, Acosta JJ, Myburg AA. (2021) A genome- wide SNP genotyping resource for tropical pine tree species. Molecular Ecology Resources 10.1111/1755-0998.13484 PDF
Swanepoel S, Oates CN, Shuey SS, Pegg GS, Naidoo S. (2021) Transcriptome analysis of Eucalyptus grandis implicates brassinosteroid signaling in defense against myrtle rust (Austropuccinia psidii). Frontiers in Forests and Global Change 4(200):778611. 10.3389/ffgc.2021.778611 PDF
Teshome DT, Zharare GE, Naidoo S. (2020) The threat of the combined effect of biotic and abiotic stress factors in forestry under a changing climate. Frontiers in Plant Science 10.3389/fpls.2020.601009 PDF
Oates C, Denby K, Myburg A, Slippers B, Naidoo S. (2020) Insect egg‐induced physiological changes and transcriptional reprogramming leading to gall formation. Plant, Cell & Environment 10.1111/pce.13930
Mhoswa L, O'Neill M, Makobatjatji MM, Oates CN, Payn KG, Slippers B, Myburg AA, Naidoo S. (2020) A Genome-Wide Association Study for resistance to the insect pest Leptocybe invasa in Eucalyptus grandis reveals genomic regions and positional candidate defence genes. Plant & Cell Physiology (pcaa057) 10.1093/pcp/pcaa057
du Toit Y, Coles DW, Mewalal R, Christie N, Naidoo S. (2020) eCALIBRATOR: A Comparative Tool to Identify Key Genes and Pathways for Eucalyptus Defense Against Biotic Stressors. Frontiers in Microbiology 11:216. 10.3389/fmicb.2020.00216
Messal M, Slippers B, Naidoo S, Bezuidt O, Kemler M. (2019) Active fungal communities in asymptomatic Eucalyptus grandis stems differ between a susceptible and resistant clone. Microorganisms 7(10):375. 10.3390/microorganisms7100375
Visser EA, Wegrzyn JL, Steenkamp ET, Myburg AA, Naidoo S. (2019) Dual RNA-Seq Analysis of the Pine-Fusarium circinatum Interaction in Resistant (Pinus tecunumanii) and Susceptible (Pinus patula) Hosts. Microorganisms 7:315. 10.3390/microorganisms7090315 PDF
Solís M, Salas A, Lagos C, Valenzuela S, Emhart V, Fernández M. (2019) De Novo Transcriptome Assembly of Eucalyptus nitens and the Expression of R2R3-MYB Genes in Response to Cold Acclimation in Eucalyptus Spp.. Plant Molecular Biology Reporter 37(4):376–388. 10.1007/s11105-019-01160-7
Naidoo S, Slippers B, Plett JM, Coles D, Oates CN. (2019) The road to resistance in forest trees. Frontiers in Plant Science 10:273. 10.3389/fpls.2019.00273
Backer R, Naidoo S, van den Berg N. (2019) The NONEXPRESSOR OF PATHOGENESIS-RELATED GENES 1 (NPR1) and Related Family: Mechanistic Insights in Plant Disease Resistance. Frontiers in Plant Science 10:102. 10.3389/fpls.2019.00102
Myriam Solís. 2019. Sensibilidad de Botrytis cinera a Switch en viveros forestales . Editorial academica española. PDF

New Publications

Backer R, Naidoo S, van den Berg N. (2023) The expression of the NPR1-dependent defense response pathway genes in Persea americana (Mill.) following infection with Phytophthora cinnamomi. BMC Plant Biology 23(1):548. 10.1186/s12870-023-04541-z PDF
Swanepoel S, Visser EA, Shuey SS, Naidoo S. (2023) The In Planta Gene Expression of Austropuccinia psidii in Resistant and Susceptible Eucalyptus grandis. Phytopathology 113(6):1066-1076. 10.1094/PHYTO-07-22-0257-R PDF
Solís M, Hammerbacher A, Wingfield MJ, Naidoo S. (2023) A robust disease scoring method to screen Eucalyptus for resistance against the aggressive leaf blight pathogen, Teratosphaeria destructans. Plant Disease:1418 - 1424. 10.1094/PDIS-06-22-1347-RE PDF
Teshome DT, Zharare GE, Ployet R, Naidoo S. (2023) Transcriptional reprogramming during recovery from drought stress in Eucalyptus grandis. Tree Physiology 10.1093/treephys/tpad022
Swanepoel S, Visser E, Shuey L, Naidoo S. (2023) The In Planta Gene Expression of Austropuccinia psidii in Resistant and Susceptible Eucalyptus grandis. PHYTOPATHOLOGY 10.1094/PHYTO-07-22-0257-R
Visser EA, Kampmann TP, Wegrzyn JL, Naidoo S. (2022) Multispecies comparison of host responses to Fusarium circinatum challenge in tropical pines show consistency in resistance mechanisms. Plant, Cell & Environment 46(5):1705-1725. 10.1111/pce.14522 PDF
Solís M, Wingfield MJ, Hammerbacher A, Naidoo S. (2022) Comparison of the infection biology of Teratosphaeria destructans and Teratosphaeria epicoccoides on Eucalyptus. Plant Disease 10.1094/PDIS-09-21-1877-RE PDF
Messal M, Vivas M, Kemler M, Begerow D, Brachmann A, Witfeld F, Naidoo S, Slippers B. (2022) Fungal Communities of Eucalyptus grandis Leaves Are Influenced by the Insect Pest Leptocybe invasa. Frontiers in Microbiology 13(3:841621) 10.3389/fmicb.2022.841621 PDF
Jackson C, Christie N, Reynolds SM, Marais GC, Tii-kuzu Y, Caballero M, Kampman T, Visser EA, Naidoo S, Kain D, Whetten RW, Isik F, Wegrzyn J, Hodge GR, Acosta JJ, Myburg AA. (2021) A genome- wide SNP genotyping resource for tropical pine tree species. Molecular Ecology Resources 10.1111/1755-0998.13484 PDF
Swanepoel S, Oates CN, Shuey SS, Pegg GS, Naidoo S. (2021) Transcriptome analysis of Eucalyptus grandis implicates brassinosteroid signaling in defense against myrtle rust (Austropuccinia psidii). Frontiers in Forests and Global Change 4(200):778611. 10.3389/ffgc.2021.778611 PDF
Teshome DT, Zharare GE, Naidoo S. (2020) The threat of the combined effect of biotic and abiotic stress factors in forestry under a changing climate. Frontiers in Plant Science 10.3389/fpls.2020.601009 PDF
Oates C, Denby K, Myburg A, Slippers B, Naidoo S. (2020) Insect egg‐induced physiological changes and transcriptional reprogramming leading to gall formation. Plant, Cell & Environment 10.1111/pce.13930
Mhoswa L, O'Neill M, Makobatjatji MM, Oates CN, Payn KG, Slippers B, Myburg AA, Naidoo S. (2020) A Genome-Wide Association Study for resistance to the insect pest Leptocybe invasa in Eucalyptus grandis reveals genomic regions and positional candidate defence genes. Plant & Cell Physiology (pcaa057) 10.1093/pcp/pcaa057
du Toit Y, Coles DW, Mewalal R, Christie N, Naidoo S. (2020) eCALIBRATOR: A Comparative Tool to Identify Key Genes and Pathways for Eucalyptus Defense Against Biotic Stressors. Frontiers in Microbiology 11:216. 10.3389/fmicb.2020.00216
Messal M, Slippers B, Naidoo S, Bezuidt O, Kemler M. (2019) Active fungal communities in asymptomatic Eucalyptus grandis stems differ between a susceptible and resistant clone. Microorganisms 7(10):375. 10.3390/microorganisms7100375
Visser EA, Wegrzyn JL, Steenkamp ET, Myburg AA, Naidoo S. (2019) Dual RNA-Seq Analysis of the Pine-Fusarium circinatum Interaction in Resistant (Pinus tecunumanii) and Susceptible (Pinus patula) Hosts. Microorganisms 7:315. 10.3390/microorganisms7090315 PDF
Solís M, Salas A, Lagos C, Valenzuela S, Emhart V, Fernández M. (2019) De Novo Transcriptome Assembly of Eucalyptus nitens and the Expression of R2R3-MYB Genes in Response to Cold Acclimation in Eucalyptus Spp.. Plant Molecular Biology Reporter 37(4):376–388. 10.1007/s11105-019-01160-7
Naidoo S, Slippers B, Plett JM, Coles D, Oates CN. (2019) The road to resistance in forest trees. Frontiers in Plant Science 10:273. 10.3389/fpls.2019.00273
Backer R, Naidoo S, van den Berg N. (2019) The NONEXPRESSOR OF PATHOGENESIS-RELATED GENES 1 (NPR1) and Related Family: Mechanistic Insights in Plant Disease Resistance. Frontiers in Plant Science 10:102. 10.3389/fpls.2019.00102
Myriam Solís. 2019. Sensibilidad de Botrytis cinera a Switch en viveros forestales . Editorial academica española. PDF