The Molecular Plant-Pathogen Interactions (MPPI) Group is located in the Plant Sciences Complex at the University of Pretoria. The group is part of the Department of Plant & Soil Sciences and the Forestry and Agricultural Biotechnology Institute (FABI) and is headed by Prof Dave Berger. Research focuses on the molecular basis of plant-pathogen interactions and the mechanisms of plant defence using a range of approaches from whole plant phenotyping to functional genomics, as well as developing bioinformatics tools. The MPPI group has particular experience in transcriptomics using microarrays and RNAseq.

The main research projects in the MPPI lab involves maize, the staple food of sub-Saharan Africa. We are interested in understanding mechanisms underlying quantitative disease resistance in maize to grey leaf spot (GLS) disease. GLS is an important constraint to maize production in many maize growing regions of the world, particularly in Africa.

We collaborate with maize breeders and field pathologists to understand the disease in its Agricultural context, which gives postgraduate students the opportunity to temporarily "escape" from the lab. Apart from glasshouse bioassays, the MPPI group is employing genomics, such as high density molecular markers, and transcriptomics to study maize defence mechanisms against GLS, with the long term aim to develop tools for maize improvement, such as marker assisted selection.

The MPPI group, together with the CFPRG in FABI, is also elucidating pathogenicity strategies employed by Cercospora zeina, the causal agent of GLS. We are taking a comparative genomics approach, through whole genome sequencing of C. zeina isolates. The research is followed up using functional genomics tools developed in the CFPRG. In addition, we are carrying out genetic diversity studies of C.zeina.

The MPPI group is hosted in the Plant Sciences Complex with excellent laboratories for plant biotechnology research, and access to phytotron and glasshouse facilities. Several bioinformatics software packages and databases have been developed by the group in collaboration with the Centre for Bioinformatics and Computational Biology at the University of Pretoria.

New Publications

Abkallo HM, Arbuthnot P, Auer TO, Berger DK, Burger J, Chakauya E, Concordet J-P, Diabate A, Di Donato V, Groenewald J-H, Guindo A, Koekemoer LL, Nazare F, Nolan T, Okumu F, Orefuwa E, Paemka L, Prieto-Godino L, Runo S, Sadler M, Tesfaye K, Tripathi L, Wondji C. (2024) Making genome editing a success story in Africa. Nature Biotechnology :1-4. https://rdcu.be/dBJUa
Omondi DO, Dida MM, Berger DK, Beyene Y, Nsibo DL, Juma C, Mahabaleswara SL, Gowda M. (2023) Combination of Linkage and Association Mapping with Genomic Prediction to Infer QTL Regions Associated with Gray Leaf Spot and Northern Corn Leaf Blight Resistance in Tropical Maize. Frontiers in Genetics 14:1-16. 10.3389/fgene.2023.1282673
Welgemoed T, Duong TA, Barnes I, Stukenbrock EH, Berger DK. (2023) Population genomic analyses suggest recent dispersal events of the pathogen Cercospora zeina into East and Southern African maize cropping systems. G3 Genes|Genomes|Genetics 10.1093/g3journal/jkad214
Wingfield BD, Berger DK, Coetzee MPA, Duong TA, Martin A, Pham NQ, Van den Berg N, Wilken PM, Arun-Chinnappa KS, Barnes I, Buthelezi S, Dahanayaka BA, Durán A, Engelbrecht J, Feurtey A, Fourie A, Fourie G, Hartley J, Kabwe ENK, Maphosa M, Narh Mensah DL, Nsibo DL, Potgieter L, Poudel B, Stukenbrock EH, Thomas C, Vaghefi N, Welgemoed T, Wingfield MJ. (2022) IMA genome‑F17 Draft genome sequences of an Armillaria species from Zimbabwe, Ceratocystis colombiana, Elsinoë necatrix, Rosellinia necatrix, two genomes of Sclerotinia minor, short‑read genome assemblies and annotations of four Pyrenophora teres isolates from barley grass, and a long-read genome assembly of Cercospora zeina. 13:19. 10.1186/s43008-022-00104-3
Craze HA, Pillay N, Joubert F, Berger DK. (2022) Deep Learning Diagnostics of Gray Leaf Spot in Maize under Mixed Disease Field Conditions. Plants 11(1942):1-17. https://bit.ly/3vg484g
Luo G-F, Podolyan A, Kidanemariam D, Pilotti C, Houliston G, Sukal AC. (2022) A review of viruses infecting Yam (Dioscorea spp.). Viruses 14(662) 10.3390/v14040662
Nsibo DL, Barnes I, Omondi DO, Dida MM, Berger DK. (2021) Population genetic structure and migration patterns of the maize pathogenic fungus, Cercospora zeina in East and Southern Africa. Fungal Genetics and Biology 149(103527) 10.1016/j.fgb.2021.103527
Pillay N, Gerber M, Holan K, Whitham SA, Berger DK. 2021. Quantifying the Severity of Common Rust in Maize Using Mask R-CNN. In: Artificial Intelligence and Soft Computing. ICAISC 2021. Lecture Notes in Artificial Intelligence, vol 12854. Rutkowski L, Scherer R, Korytkowski M, Pedrycz W, Tadeusiewicz R, Zurada J. (eds). Springer, Cham., pp 202-213.
Aveling TAS, De Ridder K, Olivier NA, Berger DK. (2020) Seasonal variation in mycoflora associated with asymptomatic maize grain from small-holder farms in two provinces of South Africa. Journal of Agriculture and Rural Development in the Tropics and Subtropics (JARTS) 121(2):265-275. 10.17170/kobra-202011262275 PDF
Berger DK, Mokgobu T, De Ridder K, Christie N, Aveling TAS. (2020) Benefits of maize resistance breeding and chemical control against northern leaf blight in smallholder farms in South Africa. South African Journal of Science 12(11) 10.17159/sajs.2020/8286
Welgemoed T, Pierneef R, Read DA, Schulze SE, Pietersen G, Berger DK. (2020) Next generation sequencing reveals past and current widespread occurrence of maize yellow mosaic virus in South Africa. European Journal of Plant Pathology 158(1):237-249. 10.1007/s10658-020-02070-1
Human MP, Berger DK, Crampton BG. (2020) Time-course RNAseq reveals Exserohilum turcicum effectors and pathogenicity determinants. Frontiers in Microbiology 11(360) 10.3389/fmicb.2020.00360
Welgemoed T, Pierneef R, Sterck L, Van de Peer Y, Swart V, Scheepers KD, Berger DK. (2020) De novo assembly of transcriptomes from a B73 maize line introgressed with a QTL for resistance to gray leaf spot disease reveals a candidate allele of a lectin receptor-like kinase. Frontiers in Plant Science http://bit.ly/2SmKPmT
Devnarain N, Crampton BG, Olivier N, van der Westhuizen C, Becker JVW, O'Kennedy MM. (2019) Transcriptomic analysis of a Sorghum bicolour landrace identifies a role for beta-alanine betaine biosynthesis in drought tolerance.. South African Journal of Botany 127 10.1016/j.sajb.2019.08.049
Zumaquero A, Martinez-Ferri E, Matas AJ, Reeksting B, Olivier NA, Pliego-Alfaro F, Barcelo A, van den Berg N, Pliego C. (2019) Rosellinia necatrix infection induces differential gene expression between tolerant and susceptible avocado rootstocks. PLoS ONE 14(2):e0212359. 10.1371/journal.pone.0212359
Nsibo DL, Barnes I, Kunene NT, Berger DK. (2019) Influence of farming practices on the population genetics of the maize pathogen Cercospora zeina in South Africa. Fungal Genetics and Biology 125:36-44. 10.1016/j.fgb.2019.01.005
Read DA, Featherstone J, Rees DJG, Thompson GD, Roberts R, Flett BC, Mashingaidze K, Berger DK, Welgemoed T, Pietersen G, Schulze SE, Kiula B, Kullaya A, Mbega E. (2019) First report of maize yellow mosaic virus (MaYMV) on maize (Zea mays) in Tanzania. Journal of Plant Pathology 101:203. 10.1007/s42161-018-0152-5
van den Berg N, Mohamed W, Olivier NA, Swart V, Crampton B. (2018) Transcriptome analysis of an incompatible Persea americana-Phytophthora cinnamomi interaction reveals the involvement of SA- and JA-pathways in a successful defense response. PLoS ONE 13(10):e0205705. 10.1371/journal.pone.0205705
Viljoen E, Odeny DA, Coetzee MPA, Berger DK, Rees DJG. (2018) Application of Chloroplast Phylogenomics to Resolve Species Relationships Within the Plant Genus Amaranthus. Journal of Molecular Evolution 86(3-4):216-239. 10.1007/s00239-018-9837-9
Liversage J, Coetzee MPA, Bluhm BH, Berger DK, Crampton BG. (2018) LOVe across kingdoms: Blue light perception vital for growth and development in plant–fungal interactions. Fungal Biology Reviews 32(2):86-103. 10.1016/j.fbr.2017.11.003
Wingfield BD, Berger DK, Steenkamp ET, Lim H-J, Duong TA, Bluhm BH, De Beer ZW, De Vos L, Fourie G, Naidoo K, Olivier NA, Lin Y, Van der Peer Y, Joubert F, Crampton BG, Swart V, Soal N, Tatham C, Van der Nest MA, Van der Merwe NA, Van Wyk S, Wilken PM, Wingfield MJ. (2017) IMA Genome-F 8 Draft genome of Cercospora zeina, Fusarium pininemorale, Hawksworthiomyces lignivorus, Huntiella decipiens and Ophiostoma ips. IMA Fungus 8 (2):385‑396. 10.5598/imafungus.2017.08.02.10 PDF
Meyer J, Berger DK, Christensen SA, Murray SL. (2017) RNA-Seq analysis of resistant and susceptible sub-tropical maize lines reveals a role for kauralexins in resistance to grey leaf spot disease, caused by Cercospora zeina. BMC Plant Biology 17:197. 10.1186/s12870-017-1137-9
Amuge T, Berger DK, Katari MS, Myburg AA, Goldman SL, Ferguson ME. (2017) A time series transcriptome analysis of cassava (Manihot esculenta Crantz) varieties challenged with Ugandan cassava brown streak virus. Scientific Reports 7:9747. 10.1038/s41598-017-09617-z
Swart V, Crampton BG, Ridenour JB, Bluhm BH, Olivier NA, Meyer JJM, Berger DK. (2017) Complementation of CTB7 in the maize pathogen Cercospora zeina overcomes the lack of in vitro cercosporin production. Molecular Plant-Microbe Interactions 30(9):710-724. 10.1094/MPMI-03-17-0054-R
Zwart L, Berger DK, Moleleki LN, Van der Merwe NA, Myburg AA, Naidoo S. (2017) Evidence for salicylic acid signalling and histological changes in the defence response of Eucalyptus grandis to Chrysoporthe austroafricana. Scientific Reports 7:45402. 10.1038/srep45402 PDF
Christie N, Myburg AA, Joubert F, Murray SL, Carstens M, Lin Y-C, Meyer J, Crampton BG, Christensen SA, Ntuli JF, Wighard SS, Van de Peer Y, Berger DK. (2017) Systems genetics reveals a transcriptional network associated with susceptibility in the maize-gray leaf spot pathosystem. The Plant Journal 89(4):746-763. 10.1111/tpj.13419
Reitmann A, Berger DK, van den Berg N. (2017) Putative pathogenicity genes of Phytophthora cinnamomi identified via RNA-Seq analysis of pre-infection structures. European Journal of Plant Pathology 147(1):211-228. 10.1007/s10658-016-0993-8
Human MP, Barnes I, Craven M, Crampton BG. (2016) Lack of population structure and mixed reproduction modes in Exserohilum turcicum from South Africa. Phytopathology 106(11):1386-1392. 10.1094/PHYTO-12-15-0311-R
Muller MF, Barnes I, Kunene NT, Crampton BG, Bluhm B, Phillips S, Olivier NA, Berger DK. (2016) Cercospora zeina from maize in South Africa exhibits high genetic diversity and lack of regional population differentiation. Phytopathology 106(10):1194-1205. 10.1094/PHYTO-02-16-0084-FI
Oelofse D, Gazendam I, Veale A, Djami-Tchatchou A, Berger D, Dubery I. (2016) Functional characterization of a defense-related class-III chitinase promoter from Lupinus albus, active in legume and monocot tissues. European Journal of Plant Pathology 146(4):923-936. 10.1007/s10658-016-0970-2