Identification and importance of soft rot Erwinias infecting potato in Mauritius
| MSI99P1002 | |
| Autrey, L. J. C. Dookun, A. | |
| Identification and importance of soft rot Erwinias infecting potato in Mauritius | |
| African Potato Association, Proceedings of the First Triannual General Meeting and Conference, Nairobi, Kenya, 21-25 June 1987 | |
| Book chapter | |
| 1989 | |
| p. 182 | |
| Nairobi, Kenya, African Potato Association | |
| Abstract only | |
| En | |
| En | |
| Soft rot of potato caused by Erwinia spp. has been known to occur in Mauritius for many years but detailed studies on the associated organisms were carried out only recently as more attention has to be given initially to bacterial wilt caused by Pseudomonas solanacearum owing to the latter's economic importance. On the basis of cultural, biochemical, physiological and serological properties Erwinia carotovora subsp. carotovora (Ecc), E. carotovora subs. atroseptica (Eca) and E. chrysanthemi (Echr) were identified from potato tubers and plants. Ecc was the most frequently encountered organism being present in 73.5 per cent of all isolates collected at random while Eca and Ech represented 26.3 and 0.2 per cent respectively. The bacterial pathogens were isolated from 11 other hosts under natural conditions indicating their wide host range and the possible role of these plants as reservoirs for disease carry-over. In spite of the absence of characteristic disease symptoms, infection by Erwinias in tubers from ware fields of varieties up-to-date, and Delaware ranged from 60 to 100 and 20 to 100 percent respectively. Extensive field surveys from 1984 to 1986 revealed that symptoms of soft rot were rarely present, being encountered in only three fields of variety up-to-date, with levels of hill infection of 12.8, 22.5 and 31.4 per cent. Glasshouse trials with varieties Mariline and Delaware with Ecc and Eca and field tests with varieties Spunta, Delaware and Up-to-date with the three Erwinias, involving three methods of inoculation, failed to demonstrate significant reduction in yield induced by the pathogen. It is concluded from these and other trials as well as from field observations that soft rot Erwinas are widespread in Mauritius but have little economic importance except in specific circumstances, in humid and warm conditions prevailing in early and late summer. | |
| POTATOES ERWINIA VARIETIES DISEASES BACTERIAL DISEASES | |
| MAURITIUS | |
| Potatoes | |
| Diseases and disease management | |
| 1992-06-19 | |
| En | |
| Mauritius Sugar Industry Research Institute | |
| LIB | |
| CAT | |
| 1 | |
| PATH |