<abstract xml:lang="en" xmlns="http://www.w3.org/1999/xhtml">Alternaria black spot of cruciferous vegetables, incited by different species of <italic>Alternaria</italic>, remains an increasing threat to <italic>Brassicaceae</italic> crops throughout the world, including Poland. <italic>Brassica</italic> plants are attacked by conidia of <italic>A. brassicae</italic> (Berk.) Sacc., <italic>A. brassicicola</italic> (Schw.) Wiltsh., <italic>A. raphani</italic> Groves &amp; Skolko, and <italic>A. alternata</italic> (Fr.) Kreissler. The pathogens have a wide spectrum of hosts, such as head cabbage, Chinese cabbage, cauliflower, broccoli, and other crucifers including cultivated and wild grown plants. <italic>Alternaria</italic> pathogens usually cause damping-off of seedlings, spotting of leaves of cabbages, blackleg of heads of cabbages, and spotting of cauliflower curds and broccoli florets. In oilseed rape, <italic>A. brassicae</italic> is the dominant invasive species, while in the cruciferous vegetables, both species, <italic>A. brassicae</italic>, and <italic>A. brassicicola</italic> are encountered. Infected seeds with spores on the seed coat or mycelium under the seed coat are the main means of distribution for these pathogens. The fungus can overwinter on susceptible weeds or crop debris and on seed plants, as well as on stecklings.Methods for disease prevention and control are based on combining agricultural management practices with chemical control. Using disease-free seeds or seeds treated with fungicides can greatly reduce disease incidence. After appearance of the first symptoms of disease, stringent fungicide spray program is an effective way to reduce losses. Many authors seem to agree, that the most economically feasible method of disease control is the development of resistant <italic>Brassicaceae</italic> crops varieties, as transgenic approach proved unsuccessful. Due to our increasing understanding of pathogen-host plant interactions, identification of resistance sources, and assessment of the resistance trait inheritance mode, breeding programs of <italic>Brassica</italic> crops for <italic>Alternaria</italic> resistance can be enhanced. This is of particular importance since recent years experience dynamic development of ecological and integrated plant production with an emphasis on plant biotic stress resistance. Highly resistant genetic resources have not been reported in <italic>Brassica</italic> cultivated species, although some varieties differ in their resistance/susceptibility level.Strong cross-incompatibility, polygenic background of the resistance (additive and dominant gene interactions), as well as the differences in ploidy between the <italic>Brassica</italic> species of interest, render the transfer of <italic>Alternaria</italic> resistance from the wild species into the cultivated forms difficult. Additionally, it is often connected with employment of <italic>in vitro</italic> hybridization techniques, including somatic hybridization, embryo and ovary rescue, or protoplast fusion.</abstract>

Alternaria black spot of cruciferous vegetables, incited by different species of Alternaria, remains an increasing threat to Brassicaceae crops throughout the world, including Poland. Brassica plants are attacked by conidia of A. brassicae (Berk.) Sacc., A. brassicicola (Schw.) Wiltsh., A. raphani Groves & Skolko, and A. alternata (Fr.) Kreissler. The pathogens have a wide spectrum of hosts, such as head cabbage, Chinese cabbage, cauliflower, broccoli, and other crucifers including cultivated and wild grown plants. Alternaria pathogens usually cause damping-off of seedlings, spotting of leaves of cabbages, blackleg of heads of cabbages, and spotting of cauliflower curds and broccoli florets. In oilseed rape, A. brassicae is the dominant invasive species, while in the cruciferous vegetables, both species, A. brassicae, and A. brassicicola are encountered. Infected seeds with spores on the seed coat or mycelium under the seed coat are the main means of distribution for these pathogens. The fungus can overwinter on susceptible weeds or crop debris and on seed plants, as well as on stecklings.Methods for disease prevention and control are based on combining agricultural management practices with chemical control. Using disease-free seeds or seeds treated with fungicides can greatly reduce disease incidence. After appearance of the first symptoms of disease, stringent fungicide spray program is an effective way to reduce losses. Many authors seem to agree, that the most economically feasible method of disease control is the development of resistant Brassicaceae crops varieties, as transgenic approach proved unsuccessful. Due to our increasing understanding of pathogen-host plant interactions, identification of resistance sources, and assessment of the resistance trait inheritance mode, breeding programs of Brassica crops for Alternaria resistance can be enhanced. This is of particular importance since recent years experience dynamic development of ecological and integrated plant production with an emphasis on plant biotic stress resistance. Highly resistant genetic resources have not been reported in Brassica cultivated species, although some varieties differ in their resistance/susceptibility level.Strong cross-incompatibility, polygenic background of the resistance (additive and dominant gene interactions), as well as the differences in ploidy between the Brassica species of interest, render the transfer of Alternaria resistance from the wild species into the cultivated forms difficult. Additionally, it is often connected with employment of in vitro hybridization techniques, including somatic hybridization, embryo and ovary rescue, or protoplast fusion.

Alternaria Black Spot of Crucifers: Symptoms, Importance of Disease, and Perspectives of Resistance Breeding

Research Institute of Horticulture, Konstytucji 3 Maja 1/3, 96-100 Skierniewice, Poland

Journal of Fruit and Ornamental Plant Research

Alternaria black spot of cruciferous vegetables, incited by different species of Alternaria, remains an increasing threat to Brassicaceae crops throughout the...

Alternaria Black Spot of Crucifers: Symptoms, Importance of Disease, and Perspectives of Resistance Breeding

Publié en ligne: 30 août 2012

Pages: 5 - 19

DOI: https://doi.org/10.2478/v10032-012-0001-6

Mots clés
spp., cruciferous plants, resistance, testing methods

This content is open access.

Alternaria Black Spot of Crucifers: Symptoms, Importance of Disease, and Perspectives of Resistance Breeding

Publié en ligne: 30 août 2012

Pages: 5 - 19

DOI: https://doi.org/10.2478/v10032-012-0001-6

Mots clésspp., cruciferous plants, resistance, testing methods

This content is open access.

Mots clés
spp., cruciferous plants, resistance, testing methods