Field Evaluation of Strawberry Genotypes for Tolerance to Black Root Rot on Fumigated and Nonfumigated Soil

Particka, Chrislyn A.; Hancock, James F.

doi:10.21273/jashs.130.5.688

Cited by 25 publications

(17 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, the phasing-out of some broad-spectrum pre-planting fumigants due to environmental and health concerns has fostered keen interest in developing alternative non-chemical ways to manage root rot and other soil-borne diseases more effectively and sustainably [23]–[26]. It is now accepted that identifying and deploying resistant cultivars is the most cost effective and environmentally sustainable strategy to control soil-borne disease on strawberry [24]–[27]. However, if novel management strategies, including the breeding of Rhizoctonia -resistant cultivars, are to be developed, it is essential to understand the genetic diversity within Rhizoctonia and how this diversity pertains to the virulence of isolates.…”

Section: Introductionmentioning

confidence: 99%

Wide Variation in Virulence and Genetic Diversity of Binucleate Rhizoctonia Isolates Associated with Root Rot of Strawberry in Western Australia

2013

View full text Add to dashboard Cite

Strawberry (Fragaria×ananassa) is one of the most important berry crops in the world. Root rot of strawberry caused by Rhizoctonia spp. is a serious threat to commercial strawberry production worldwide. However, there is no information on the genetic diversity and phylogenetic status of Rhizoctonia spp. associated with root rot of strawberry in Australia. To address this, a total of 96 Rhizoctonia spp. isolates recovered from diseased strawberry plants in Western Australia were characterized for their nuclear condition, virulence, genetic diversity and phylogenetic status. All the isolates were found to be binucleate Rhizoctonia (BNR). Sixty-five of the 96 BNR isolates were pathogenic on strawberry, but with wide variation in virulence, with 25 isolates having high virulence. Sequence analysis of the internal transcribed spacers of the ribosomal DNA separated the 65 pathogenic BNR isolates into six distinct clades. The sequence analysis also separated reference BNR isolates from strawberry or other crops across the world into clades that correspond to their respective anastomosis group (AG). Some of the pathogenic BNR isolates from this study were embedded in the clades for AG-A, AG-K and AG-I, while other isolates formed clades that were sister to the clades specific for AG-G, AG-B, AG-I and AG-C. There was no significant association between genetic diversity and virulence of these BNR isolates. This study demonstrates that pathogenic BNR isolates associated with root rot of strawberry in Western Australia have wide genetic diversity, and highlights new genetic groups not previously found to be associated with root rot of strawberry in the world (e.g., AG-B) or in Australia (e.g., AG-G). The wide variation in virulence and genetic diversity identified in this study will be of high value for strawberry breeding programs in selecting, developing and deploying new cultivars with resistance to these multi-genetic groups of BNR.

show abstract

Section: Introductionmentioning

confidence: 99%

Wide Variation in Virulence and Genetic Diversity of Binucleate Rhizoctonia Isolates Associated with Root Rot of Strawberry in Western Australia

2013

View full text Add to dashboard Cite

show abstract

“…breeding programs where selections were concluded based upon growth in fumigated soils, which yielded varieties that are highly susceptible to a wealth of soilborne pathogens. While the highly methyl bromide fumigation-dependent strawberry material from the California breeding system initially yielded no obvious genetic diversity for developing cultivars adapted to sublethal effects of organisms in nonfumigated soils (Shaw and Larson 1996), tolerance to black root rot, incited by a complex of non-lethal pathogens, was detected among three genotypes released from the breeding program in Nova Scotia, Canada (Particka and Hancock 2005).…”

Section: Selection In Environments That Favor Progeny With Introgressmentioning

confidence: 99%

Novel approaches in plant breeding for rhizosphere-related traits

2008

View full text Add to dashboard Cite

Selection of modern varieties has typically been performed in standardized, high fertility systems with a primary focus on yield. This could have contributed to the loss of plant genes associated with efficient nutrient acquisition strategies and adaptation to soil-related biotic and abiotic stresses if such adaptive strategies incurred a cost to the plant that compromised yield. Furthermore, beneficial interactions between plants and associated soil organisms may have been made obsolete by the provision of nutrients in high quantity and in readily plant available forms. A review of evidence from studies comparing older traditional varieties to modern high yielding varieties indeed showed that this has been the case. Given the necessity to use scarce and increasingly costly fertilizer inputs more efficiently while also raising productivity on poorer soils, it will be crucial to reintroduce desirable rhizosphere-related traits into elite cultivars. Traits that offer possibilities for improving nutrient acquisition capacity, plantmicrobe interactions and tolerance to abiotic and biotic soil stresses in modern varieties were reviewed. Despite the considerable effort devoted to the identification of suitable donors and of genetic factors associated with these beneficial traits, progress in developing improved varieties has been slow and has so far largely been confined to modifications of traditional breeding procedures. Modern molecular tools have only very recently started to play a rather small role. The few successful cases reviewed in this paper have shown that novel breeding approaches using molecular tools do work in principle. When successful, they involved close collaboration between breeders and scientists conducting basic research, and confirmation of phenotypes in field tests as a 'reality check'. We concluded that for novel molecular approaches to make a significant contribution to breeding for rhizosphere related traits it will be essential to narrow the gap between basic sciences and applied breeding through more interdisciplinary research that addresses rather than avoids the complexity of plant-soil interactions.

show abstract

“…fragariae), Verticillium wilt (Verticillium spp. ), and black root rot that can cause a field to fail (Particka and Hancock, 2005;Sanford et al, 1985). These diseases are not easy to diagnose unless samples are taken during a short time span, often before the symptoms become severe.…”

Section: Discussionmentioning

confidence: 99%