Neonectria ditissima spore release in apple plants and detached branches in Brazil

Araújo, Leonardo; Pinto, Felipe Augusto Moretti Ferreira

doi:10.1007/s42161-022-01207-x

Cited by 2 publications

(5 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Without redistribution, rain-dispersed spores rarely travel further than 1 m from their source (Vidal et al, 2017). However, N. ditissima conidia have been shown to disperse up to 4 m from a source as measured by a disease gradient in Brazil (Araujo and Pinto, 2022). Based on our suggested differences in dispersal decay with and without canopy, redistribution with an apple canopy could result in even greater potential dispersal 1 N-S is along the tree row.…”

Section: Discussionmentioning

confidence: 83%

“…Neonectria ditissima, the causal agent of apple canker (also called European canker), is an ascomycete fungus which can produce two spore types year round, with seasonal peaks (Amponsah et al, 2015;Amponsah et al, 2017;Araujo and Pinto, 2022): ascospores from perithecia (sexual spores) and conidia from sporodochia (asexual spores). Conidia range from small singlecelled microconidia to relatively large multi-celled cylindrical spores (macroconidia, up to approximately 76 × 7 mm) which form in spore piles (sporodochia), while ascospores are two-celled and approximately 14 × 7 mm (Araujo et al, 2021).…”

Section: Introductionmentioning

confidence: 99%

“…Conidia range from small singlecelled microconidia to relatively large multi-celled cylindrical spores (macroconidia, up to approximately 76 × 7 mm) which form in spore piles (sporodochia), while ascospores are two-celled and approximately 14 × 7 mm (Araujo et al, 2021). Conidia are released and spread by rain (Amponsah et al, 2017;Araujo and Pinto, 2022) and most conidia are generally released within the first 30 minutes of rain (Walter et al, 2018). Ascospores can be actively released but are found only during, or after rainfall, and can also be collected in passive rainfall traps (Amponsah et al, 2017;Araujo and Pinto, 2022).…”

Section: Introductionmentioning

confidence: 99%

“…Conidia are released and spread by rain (Amponsah et al, 2017;Araujo and Pinto, 2022) and most conidia are generally released within the first 30 minutes of rain (Walter et al, 2018). Ascospores can be actively released but are found only during, or after rainfall, and can also be collected in passive rainfall traps (Amponsah et al, 2017;Araujo and Pinto, 2022). The seasonality of spore types varies with region, and in New Zealand apple orchards, lesions producing conidia are found more frequently than those producing perithecia (Campbell et al, 2016).…”

Section: Introductionmentioning

confidence: 99%

“…Dispersal distances of N. ditissima conidia have been recorded of between 1 and 4 m for conidia (Nunes and Alves, 2019;Araujo and Pinto, 2022), and ascospores have the potential to travel hundreds of meters to a few kilometers (Weber, 2014). However, dispersal distances have not been adequately quantified.…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Methods for quantifying rain-splash dispersal of Neonectria ditissima conidia in apple canopies

Campbell,

Wallis,

Walter

2023

Front. Hortic.

View full text Add to dashboard Cite

Many microorganisms can be dispersed by rain-splash, whereby spores become suspended in water and are spread via droplets. The resulting dispersal gradient is dependent on several factors including rainfall intensity, the nature of the plant canopy and its effects on splash, deposition, redistribution (secondary splash) and filtering. Gradients of spore dispersal with distance are important for understanding epidemics, and the primary dispersal gradient can shape an epidemic for several pathogen generations. However, microorganisms are difficult to trap, identify and enumerate efficiently. This makes it difficult to study the spread and dispersal of pathogens to aid in biosecurity responses and management of epidemics. We used macroconidia of Neonectria ditissima, the causal organism of apple canker, to explore patterns of rain-splash dispersal in tree canopies. We investigated the use of a fluorescent tracer dye, PTSA (1,3,6,8-pyrenetetrasulfonic acid), as a surrogate to conidia capture during natural and artificial rain events, and lens tissue as ‘surrogate leaves’ to recapture tracer dye. Conidia and dye were released from central point sources 2.5 m above the ground and recaptured in passive rainwater traps or artificial ‘leaves’. Quantile regression and exponential models were used to explore variation and dispersal gradients derived for both conidia and dye, with and without tree canopy and with natural or artificial precipitation. Estimated dispersal gradients were steeper with a flatter tail when no tree canopy was present, whereas presence of tree canopy resulted in more variation and shallower predicted dispersal gradients, with fatter tails, predicting potential dispersal to further distances from the source. The majority of conidia and dye were recaptured at less than 1 m from the source, but small concentrations of spores were detected up to 3 m and dye more than 6 m. High variation in natural conditions requires further investigation to fully quantify natural dispersal gradients. Nevertheless, these results show the merit of tracer dye, artificial leaves, and quantile regression as tools to estimate potential dispersal patterns of N. ditissima and other rain-splash dispersed microorganisms, considering rain-splash factors in real canopies and natural situations for predicting inoculum dispersal.

show abstract

Section: Discussionmentioning

confidence: 83%

Section: Introductionmentioning

confidence: 99%