Species and mating types of Phytophthora on cocoa in Jamaica and their effect on selected cocoa varieties
In a disease survey of cocoa in Jamaica, infected samples yielded mainly Phytophthora palmivora and Colletotrichum gloeosporioides, with low levels of Fusarium sp., Thielaviopsis paradoxa and P. capsici. This is the first record of P. capsici on cocoa in Jamaica. The A1 mating type of P. palmivora was found to be generally predominant, but the A2 mating type was locally dominant in areas such as Orange River Agricultural Station. The two mating types were of equal virulence on pods of varieties ICS 1, ICS 60 and ICS 95 in terms of percentage infected and lesion size produced, but ICS 95 showed the highest sporulation levels with A2 isolates. In pathogenicity tests with 14 isolates of P. palmivora, ICS 1 showed the greatest susceptibility to pod rot. All three varieties were resistant to P. capsici which was significantly less virulent than P. palmivora.
| Main Author: | |
|---|---|
| Format: | biblioteca |
| Published: |
Oct
|
| Subjects: | THEOBROMA CACAO, PHYTOPHTHORA PALMIVORA, PHYTOPHTHORA CAPSICI, ENFERMEDADES FUNGOSAS, AISLAMIENTOS, PODER PATOGENO, MICROSCOPIA, JAMAICA, |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| Summary: | In a disease survey of cocoa in Jamaica, infected samples yielded mainly Phytophthora palmivora and Colletotrichum gloeosporioides, with low levels of Fusarium sp., Thielaviopsis paradoxa and P. capsici. This is the first record of P. capsici on cocoa in Jamaica. The A1 mating type of P. palmivora was found to be generally predominant, but the A2 mating type was locally dominant in areas such as Orange River Agricultural Station. The two mating types were of equal virulence on pods of varieties ICS 1, ICS 60 and ICS 95 in terms of percentage infected and lesion size produced, but ICS 95 showed the highest sporulation levels with A2 isolates. In pathogenicity tests with 14 isolates of P. palmivora, ICS 1 showed the greatest susceptibility to pod rot. All three varieties were resistant to P. capsici which was significantly less virulent than P. palmivora. |
|---|