Studies of Resistance to Sharka (Plum Pox) in Romanian Apricot Progenies

Sharka (Plum pox) is considered one of the most devastating diseases of stone fruits in terms of agronomic impact and economic importance. The response of several apricot hybrids was evaluated over the vegetative period of 2010 by visual monitoring of symptom development and by serological and molecular methods. After two cycles of study, all the replicates of ‘Mari de Cenad’, ‘Traian’ and ‘Tabriz’ showed sharka symptoms while the replicates of ‘Stark Early Orange’ and NJA 2 did not show any symptoms and were not ELISA-positive. The resistant progenitors (‘Stark Early Orange’, NJA17, NJA42 and NJA2) were able to transmit PPV resistance to their descendants, in agreement with previous results (DOSBA et al, 1994, MARTINEZ-GOMEZ et al, 2000; AUDERGON et al, 1994). The genetic control hypotheses for PPV resistance in apricot referenced by different authors considered the resistance allele as dominant. Romanian apricot F1 and F2 progenies evaluated were classified into two groups: susceptible to PPV and resistant to PPV. After that the most important genotypes were grafted onto infected GF 305 (considered as indicator for PPV) in greenhouse conditions. The final step is the introduction and development of the marker-assisted selection (MAS) in PPV resistance F1 and F2 progenies in apricot Romanian genotypes. DNA was isolated from all hybrids and parent genotypes. These samples will be used to implement the molecular markers for identification of genes linked to plant response to PPV infection.

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Candidatus Liberibacter: From Movement, Host Responses, to Symptom Development of Citrus HLB

Phytopathology ◽

10.1094/phyto-08-21-0354-fi ◽

2021 ◽

Author(s):

Sheo Shankar Pandey ◽

Connor Hendrich ◽

Maxuel Andrade ◽

Nian Wang

Keyword(s):

Genetic Information ◽

Expression Profiles ◽

Economic Importance ◽

Type Iv Pili ◽

Host Responses ◽

Symptom Development ◽

Type Iv ◽

Tremendous Progress ◽

Candidatus Liberibacter ◽

Citrus Disease

Candidatus Liberibacter spp. are fastidious α-proteobacteria that cause multiple diseases on plants hosts of economic importance, including the most devastating citrus disease: Huanglongbing (HLB). HLB was reported in Asia a century ago, but has since spread worldwide. Understanding the pathogenesis of Candidatus Liberibacter spp. remains challenging as they are yet to be cultured in artificial media and infect the phloem, a sophisticated environment that is difficult to manipulate. Despite those challenges, tremendous progress has been made on Ca. Liberibacter pathosystems. Here, we first reviewed recent studies on genetic information of flagellar and type IV pili biosynthesis, their expression profiles, and movement of Ca. Liberibacter spp. inside the plant and insect hosts. Next, we reviewed the transcriptomic, proteomic and metabolomic studies of susceptible and tolerant plant genotypes to Ca. Liberibacter spp. infection and how Ca. Liberibacter spp. adapt in plants. Analyses of the interactions between plants and Ca. Liberibacter spp. imply the involvement of immune response in the Ca. Liberibacter pathosystems. Lastly, we reviewed how Ca. Liberibacter spp. movement inside and interactions with plants lead to symptom development.

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SPInDel Analysis of the Non-Coding Regions of cpDNA as a More Useful Tool for the Identification of Rye (Poaceae: Secale) Species

International Journal of Molecular Sciences ◽

10.3390/ijms21249421 ◽

2020 ◽

Vol 21 (24) ◽

pp. 9421

Author(s):

Lidia Skuza ◽

Ewa Filip ◽

Izabela Szućko ◽

Jan Bocianowski

Keyword(s):

Mitochondrial Dna ◽

Molecular Markers ◽

Related Species ◽

Economic Importance ◽

Closely Related Species ◽

Coding Sequences ◽

Coding Regions ◽

Genomic Regions ◽

Tribe Triticeae

Secale is a small but very diverse genus from the tribe Triticeae (family Poaceae), which includes annual, perennial, self-pollinating and open-pollinating, cultivated, weedy and wild species of various phenotypes. Despite its high economic importance, classification of this genus, comprising 3–8 species, is inconsistent. This has resulted in significantly reduced progress in the breeding of rye which could be enriched with functional traits derived from wild rye species. Our previous research has suggested the utility of non-coding sequences of chloroplast and mitochondrial DNA in studies on closely related species of the genus Secale. Here we applied the SPInDel (Species Identification by Insertions/Deletions) approach, which targets hypervariable genomic regions containing multiple insertions/deletions (indels) and exhibiting extensive length variability. We analysed a total of 140 and 210 non-coding sequences from cpDNA and mtDNA, respectively. The resulting data highlight regions which may represent useful molecular markers with respect to closely related species of the genus Secale, however, we found the chloroplast genome to be more informative. These molecular markers include non-coding regions of chloroplast DNA: atpB-rbcL and trnT-trnL and non-coding regions of mitochondrial DNA: nad1B-nad1C and rrn5/rrn18. Our results demonstrate the utility of the SPInDel concept for the characterisation of Secale species.

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Procedures of sire selection, sampling and application of new technology

BSAP Occasional Publication ◽

10.1017/s0263967x00031748 ◽

1995 ◽

Vol 19 ◽

pp. 9-12

Author(s):

O. Meland

Keyword(s):

Genetic Marker ◽

Marker Assisted Selection ◽

Selection Criteria ◽

New Technology ◽

Economic Value ◽

Economic Importance ◽

Progeny Test ◽

Progeny Testing ◽

Selection Methods ◽

Test Programme

AbstractThe objective of any well designed progeny test programme is to identify those individuals that have inherited the favourable genes from his parents. Bulls that enter a progeny test programme have been highly selected on a set of selection criteria. The criteria vary among organizations based upon their breeding philosophy and their prediction of the future economic value of various traits. The accuracy of choosing among this highly selected group is quite low. Increasing the accuracy of selection before progeny testing is the greatest potential application of genetic marker technology. Markers associated with traits of importance can greatly enhance traditional selection methods by increasing the prospect of an individual having the desired characteristics. Genetic marker-assisted selection can greatly increase the actual genetic merit of traits of economic importance

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Brown rot of stone fruits on the Murrumbidgee Irrigation Areas. II. Aetiology of the disease in Trevatt apricot trees

Australian Journal of Agricultural Research ◽

10.1071/ar9690317 ◽

1969 ◽

Vol 20 (2) ◽

pp. 317 ◽

Cited By ~ 6

Author(s):

PF Kable

Keyword(s):

Brown Rot ◽

Economic Importance ◽

Fruit Rot ◽

Monilinia Fructicola ◽

Stone Fruits

Blossom blight is of economic importance in apricots on the Murrumbidgee Irrigation Areas (MIA), but fruit rot is not. Monilinia fructicola generally does not overwinter effectively in apricot trees in the MIA, the inocula for primary infections coming from nearby peach plantations. Blighted blossoms in apricot trees, which flower a week before peaches, may provide inoculum for blighting of flowers in the latter crop. In apricot trees, unlike peach, there is a continuous infection chain from flowering till harvest. Inoculum may pass from apricot to peach in December and January, thus bridging a gap in the infection chain in peach. The infection chain in apricot is described. Latent and quiescent infections were observed. The implications of the exchange of inoculum between peach and apricot are discussed.

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