Botryosphaeriaceae species associated with wood diseases of stone and pome fruits trees: symptoms and virulence across different hosts in Uruguay

• Published in: European journal of plant pathology Vol. 146; no. 3; pp. 519 - 530
• Main Authors: Sessa, Lucia, Abreo, Eduardo, Bettucci, Lina, Lupo, Sandra
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01-11-2016; Springer Nature B.V
• Subjects: Agriculture; Apples; Biomedical and Life Sciences; Botryosphaeria dothidea; Diplodia; Diplodia mutila; Ecology; Fruit trees; Fruits; Fungi; Life Sciences; Malus; Orchards; Pathogens; Plant diseases; Plant Pathology; Plant Sciences; Plant species; Prunus; Prunus persica; Pyrus communis; Seriata; Shoots; Wood; Fungi; Wood disease; Apple; Pear; Peach
• ISSN: 0929-1873; 1573-8469
• DOI: 10.1007/s10658-016-0936-4

Apple, pear and peach orchards are usually planted in close proximity, and they might share pathogenic fungal species affecting different plant organs. In particular, species of Botryosphaeriaceae have been indicated as responsible for wood diseases in these fruit species. Symptoms frequently observed in Uruguay include papyraceous cankers in apple trunks, dead shoots in pears, and gummosis in peach shoots and branches. Symptomatic tissues of these species were sampled, and fungi resembling species within Botryosphaeriaceae were isolated and identified based on phylogenetic analysis of the internal transcribed spacer region (ITS), part of the translation elongation factor 1-α gene (EF1-α) and part of the RNA polymerase II subunit gen (RPB2). Pathogenicity of selected isolates was assessed under laboratory and field conditions.
Botryosphaeria dothidea
,
Diplodia seriata
and
Neofusicoccum parvum
were isolated from the three hosts from symptomatic tissues. However, only
N. parvum
proved to be pathogenic when inoculated on trees of all three species, while
D. seriata
showed pathogenicity towards apple and peach trees only.
Diplodia mutila
and
N. australe
were isolated less frequently and not from all the host species. However, they were the most virulent based on lesion length on all tested plant species. The fact that fungal isolates obtained from one host could cause disease symptoms also in some of the alternative hosts suggests that cross infections are possible between apple, pear and peach trees. Finally,
Diplodia pseudoseriata
in
Prunus persica
and
Diplodia mutila
in
Pyrus communis
, are new records for these hosts in Uruguay.