Symptom development and latent period of <i>Austropuccinia psidii</i> (myrtle rust) in relation to host species, temperature, and ontogenic resistance

Beresford, R.; Shuey, Louise S.; Pegg, Geoff S.

doi:10.1111/ppa.13145

Cited by 29 publications

(25 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Germination of wind-borne urediniospores requires the presence of free water, darkness and optimal temperatures between 15 and 25 °C, with cuticular penetration occurring in susceptible hosts within 12 hours (Hunt 1968). During extended cold periods (∼8 °C) the pathogen can overwinter in a dormant state within the host plant (Beresford et al 2020). The pathogen causes disease symptoms on the new foliage, stems and buds (Tobias et al 2015; Carnegie et al 2015) of a wide range of perennial plants with over 480 known host species globally (Soewarto et al 2019).…”

Section: Introductionmentioning

confidence: 99%

Austropuccinia psidii, causing myrtle rust, has a gigabase-sized genome shaped by transposable elements

Tobias

Schwessinger

Deng

et al. 2020

Preprint

View full text Add to dashboard Cite

Austropuccinia psidii, originating in South America, is a globally invasive plant pathogen causing rust disease on Myrtaceae. Several biotypes are recognized with the most widely distributed pandemic strain spreading throughout the Asia-Pacific and Oceania regions within the last decade. Austropuccinia psidii has a broad host range (currently 480 myrtaceous species), making it a particularly dangerous plant pathogen. In the nine years since the pandemic biotype was first found in Australia in 2010, the pathogen has caused the near extinction of at least three species, the decline of at least one keystone species, and negatively affected commercial production of several Myrtaceae. To enable molecular and genomic studies into A. psidii pathogenicity, we assembled a highly contiguous genome for the pandemic biotype based on PacBio sequence data and scaffolding with Hi-C technology. With an estimated haploid genome size of just over 1 Gbp, it is the largest assembled fungal genome to date. We found the A. psidii genome to have a lower GC content (33.8 %), greatly expanded telomeric and intergenic regions and more repetitive regions (> 90 %) compared to other genomes of species in the Pucciniales, however numbers of predicted coding regions (18,875) are comparable. Most of the increase in genome size is caused by a recent expansion of transposable elements belonging to the Gypsy superfamily. Post-inoculation mRNA sequence capture from a susceptible host provides expression evidence for 10,613 predicted coding genes, including 210 of the 367 putative effectors. The completeness of the genome provides a greatly needed resource for strategic approaches to combat disease spread.3

show abstract

Section: Introductionmentioning

confidence: 99%

Austropuccinia psidii, causing myrtle rust, has a gigabase-sized genome shaped by transposable elements

Tobias

Schwessinger

Deng

et al. 2020

Preprint

View full text Add to dashboard Cite

show abstract

“…However, there is scarce information about the drivers of telia production for A. psidii and the influence of environment, host, and strains are yet to be determined. It is still More severe symptoms were recorded on K. robusta and L. scoparium when the inoculation was repeated after pruning, highlighting the importance of plant growth rates and timing of inoculation in determining vulnerability (Beresford et al, 2020). Both Kunzea spp.…”

Section: Discussionmentioning

confidence: 99%

“…robusta and L . scoparium when the inoculation was repeated after pruning, highlighting the importance of plant growth rates and timing of inoculation in determining vulnerability (Beresford et al, 2020). Both Kunzea spp.…”

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

“…However, artificial screening cannot replace field tests. Myrtaceae plants have different phenological characteristics and react differently to pathogen exposure under different growing environments (Beresford et al, 2018(Beresford et al, , 2020, and pathogen growth and latency, as well as disease expression, are also strongly influenced by environmental conditions. As an example, the levels of infection observed on L. scoparium and K. robusta species inoculated under controlled conditions with the pandemic strain have so far not been observed under natural conditions in New Zealand (Toome-Heller et al, 2020).…”

Section: Discussionmentioning

confidence: 99%

See 2 more Smart Citations

Susceptibility of native New Zealand Myrtaceae to the South African strain of Austropuccinia psidii: A biosecurity threat

et al. 2020

Self Cite

View full text Add to dashboard Cite

Austropuccinia psidii, cause of myrtle rust, has spread globally where Myrtaceae occur. Multiple strains of A. psidii have been identified, including a unique strain found only in South Africa. The South African strain is a biosecurity concern for species of Myrtaceae worldwide. This is because preliminary testing of South African Myrtaceae suggests it could have a wide host range, and thus has the potential to be invasive. In this study, we assessed the ability of the South African strain to infect other species of Myrtaceae by testing the susceptibility of New Zealand provenance Myrtaceae. Seedlings of four native New Zealand Myrtaceae species (Metrosideros excelsa, Leptospermum scoparium, Kunzea robusta, and Kunzea linearis) were artificially inoculated in South Africa with a single‐uredinium isolate of the South African strain. Fourteen days after inoculation, uredinia, and in many cases telia, had developed on the young leaves and stems of all four host species, which led to shoot tip dieback in the more severe cases. When comparisons were made between the species, K. robusta was the least susceptible to the South African strain of A. psidii, while L. scoparium and M. excelsa were the most susceptible. While only a limited number of seed families were tested, only a small proportion of the seedlings showed resistance to infection by the South African strain. This preliminary testing highlights the potential invasive risk the South African strain poses to global Myrtaceae communities, including New Zealand Myrtaceae.

show abstract

Putative biotic drivers of plant phenology: With special reference to pathogens and deciduousness

Burdon

Bartlett

2022

Ecology and Evolution

View full text Add to dashboard Cite

Plant phenology is not only manifested in the seasonal timing of vegetative and reproductive processes but also has ontogenetic aspects. The adaptive basis of seasonal phenology has been considered mainly in terms of climatic drivers. However, some biotic factors as likely evolutionary influences on plants’ phenology appear to have been under‐researched. Several specific cases of putative biotic factors driving plant phenology are outlined, involving both herbivores and pathogens. These illustrate the diversity of likely interactions rather than any systematic coverage or review. Emphasis is on woody perennials, in which phenology is often most multifaceted and complicated by the ontogenetic aspect. The complete seasonal leaf fall that characterizes deciduous plants may be a very important defense against some pathogens. Whether biotic influences drive acquisition or long‐term persistence of deciduousness is considered. In one case, of leaf rusts in poplars, countervailing influences of the rusts and climate suggest persistence. Often, however, biotic and environmental influences likely reinforce each other. The timing and duration of shoot flushing may in at least some cases contribute to defenses against herbivores, largely through brief periods of “predator satiation” when plant tissues have highest food value. Wide re‐examination of plant phenology, accommodating the roles of biotic factors and their interplays with environments as additional adaptive drivers, is advocated toward developing and applying hypotheses that are observationally or experimentally testable.

show abstract

Symptom development and latent period of Austropuccinia psidii (myrtle rust) in relation to host species, temperature, and ontogenic resistance

Cited by 29 publications

References 31 publications

Austropuccinia psidii, causing myrtle rust, has a gigabase-sized genome shaped by transposable elements

Austropuccinia psidii, causing myrtle rust, has a gigabase-sized genome shaped by transposable elements

Susceptibility of native New Zealand Myrtaceae to the South African strain of Austropuccinia psidii: A biosecurity threat

Putative biotic drivers of plant phenology: With special reference to pathogens and deciduousness

Contact Info

Product

Resources

About