The advent of next-generation sequencing (NGS) technologies has revolutionised research capacity and its broad applicability over the past decade. These technologies have directly impacted researchers’ ability to understand host-pathogen interactions, holistically, and on a molecular scale. Recently, the avocado industry has begun to unravel some of the underlying mysteries that pertain to prevalent avocado pests and diseases; the Avocado Research Programme (ARP) has been highly influential in this space.

As a founding member of the Avocado Genome Consortium - an international collaborative effort which was established in 2016 - the ARP has directly contributed to the development of a high quality, chromosome-level reference genome assembly for Persea americana (avocado). The Avocado Genome Consortium has used this new reference genome to re-sequence more than 10 additional cultivars and rootstocks as part of an ongoing project, with plans to increase this number soon. Provided with this data, researchers will be able to accelerate the arduous process of selecting rootstocks and cultivars with desirable traits.

As part of the broader objectives of the Avocado Genome Consortium, transcriptomic data has also been generated. This data will be utilized to answer fundamental questions pertaining to the evolutionary biology, gene expression, physiological processes, and molecular pathways in avocado. Transcriptomic data from a dual RNA-sequencing experiment - involving both susceptible and partially resistant avocado rootstocks challenged with Phytophthora cinnamomi - was also used to identify avocado defence targets and discovery of pathogen effectors involved in disease development. The data from this work has been published across several research articles and will be used to further our understanding of the avocado-P. cinnamomi interaction.

 

The researchers involved are:

  • David Kuhn, USDA, Florida
  • Patricia Manosalva, UCR, California
  • Noëlani van den Berg, UP, South Africa
  • Antonio Javier Matas Arroyo, Departamento de Biología Vegetal, University of Malaga, Spain
  • Aureliano Bombarley Gomez, Virginia Tech Horticulture, USA
  • Randy Ploetz, University of Florida, USA
  • Alan Chambers, University of Florida, USA

 

New Publications

Hlongwane NL, Dzomba EF, Hadebe K, van der Nest MA, Pierneef R, Muchadeyi FC. (2024) Identification of signatures of positive selection that have shaped the genomic landscape of South African pig populations. Animals 14:235. 10.3390/ani14020236
De Vos L, van der Nest MA, Santana QC, van Wyk S, Leeuwendaal KS, Wingfield BD, Steenkamp ET. (2024) Chromosome-level assemblies for the pine pitch canker pathogen Fusarium circinatum. Pathogens 13(1):70. 10.3390/pathogens13010070
Joubert M, van den Berg N, Theron J, Swart V. (2024) Global transcriptomic analysis in avocado nursery trees reveals differential gene expression during asymptomatic infection by avocado sunblotch viroid (ASBVd). Virus Research 339:199263. 10.1016/j.virusres.2023.199263. PDF
Anbu SP, Swart V, van den Berg N. (2023) Unmasking the invaders: NLR-mal function in plant defense. Frontiers in Plant Science 14:1307294. 10.3389/fpls.2023.1307294 PDF
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
Kooverjee BB, Soma P, van der Nest MA, Scholtz MM, Neser FWC. (2023) Copy Number Variation Discovery in South African Nguni-Sired and Bonsmara-Sired Crossbred Cattle. Animals 13(15):2513. 10.3390/ani13152513
Dzomba EF, Van der Nest MA, Mthembu JNT, Soma P, Snyman MA, Chimonyo M, Muchadeyi FC. (2023) Selection signature analysis and genome-wide divergence of South African Merino breeds from their founders. Frontiers in Genetics 13:932272. 10.3389/fgene.2022.932272
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
Swalarsk Parry BS, Steenkamp ET, Van Wyk S, Santana QC, van der Nest MA, Hammerbacher A, Wingfield BD, De Vos L. (2022) Identification and characterization of a QTL for growth of Fusarium circinatum on pine-based medium. Journal of Fungi 8(11):1214. 10.3390/jof8111214
Wienk R, Mostert‑O’Neill M, Abeysekara N, Manosalva P, Freeman B, van den Berg N. (2022) Genetic diversity, population structure and clonal verification in South African avocado cultivars using single nucleotide polymorphism (SNP) markers. Tree Genetics and Genomes 18(41) 10.1007/s11295-022-01573-8 PDF