MSI99P0125 | |
Ferré, P. Autrey, L. J. C. | |
Evaluating fungicides against leaf blights of potato in Mauritius | |
African Potato Association, Proceedings of the First Triannual General Meeting and Conference, held in Nairobi, Kenya, 21-27 June 1987 | |
Book chapter | |
1989 | |
p. 152-165 | |
African Potato Association | |
En | |
En | |
Late blight (Phytopthtora infestans), one of the most important diseases of potato in Mauritius, is prevalent in the humid and superhumid regions of the island, where annual precipitation ranges between 1250 and 3000 mm. In the early 1970's application of Mancozeb even at very high dosages and very frequent intervals proved unsatisfactory against the disease and heavy crop losses were often encountered. Systemic fungicide Cymoxanil, in combination with Mancozeb gave much better control of the fungus and with the advent of Ridomil (Metalaxyl) applied also in combination with Mancozeb, the importance of late blight as a yield reducing factor was almost totally nullified. However, owing to the possible appearance of Metalaxyl-resistant strains, seven fungicides, namely: Metiram, Chlorothalonil, Cyprofuram, Oxadixyl, Propinebe, Copper Oxychloride and Folpet applied alone or in combination, have been evaluated between 1980 and 1986 so as to provide a substitute against such strains. Only a combination of Oxydixyl, Propinebe and Cymoxanil with almost equivalent potential to Metalaxyl has been identified. With the excellent control obtained with Metalxyl early blight (Alternaria solani), which was relatively unimportant, was found to induce premature, and often severe defoliation, in potato plantings, especially in crops grown in the humid zone from July to November. Adequate control of the fungal disease was obtained with the systemic fungicide Iprodione while Vinclozolin appeared promising. It is considered that, with the fungicide treatments recommended followiing experimentation, negligible losses are being induced by leaf blights in potato at present in Mauritius in spite of the cultivation of varieties highly susceptible to these diseases. With the release of less susceptible varieties like Spunta, Exodus, Lola, Sahel and BR67-76 the situation is likely to improve further. | |
POTATOES FUNGICIDES PHYTOPHTHORA INFESTANS VARIETIES FUNGAL DISEASES DISEASES LEAF BLIGHT | |
MAURITIUS | |
Potatoes: Diseases and disease management | |
Fungal diseases: Late blight | |
1992-02-10 | |
En | |
Mauritius Sugar Industry Research Institute | |
LIB | |
CAT | |
1 | |
PATH |