|ISHS Acta Horticulturae 992: IX International Mango Symposium
SCREENING AND CROSS-RESISTANCE ANALYSIS OF ALTERNATIVE FUNGICIDES AGAINST CARBENDAZIM-RESISTANT COLLETOTRICHUM GLOEOSPORIOIDES PENZ. FROM MANGO (MANGIFERA INDICA L.)
|Authors: ||L.H. Zhang, M. Li, Z.Y. Gao, Z.K. Zhang, F.Z. Yang, Y.X. Xie, M.J. Hu, Y. Yang|
|Keywords: ||mango, Colletotrichum gloeosporioides Penz., fungicides, screening, cross-resistance|
In order to screen alternative fungicides for carbendazim-resistant Colletotrichum gloeosporioides Penz. from mango (Mangifera indica L.), the toxicity of 23 fungicides to four isolates of carbendazim-resistant and four isolates of carbendazim -sensitive C. gloeosporioides was tested by mycelium growth rate methods.
Results were analyzed using the EC50 value, the EC90 value and cross-resistance to each other.
Prochloraz was most toxic to C. gloeosporioides, with the average values of 0.04 mg/L (EC50 value) and 0.21 mg/L (EC90 value), followed by difenoconazole, propiconazole, pyraclostrobin, flusilazole, flusilazole•famoxadone, tebuconazole, myclobutanil and polyoxin.
These fungicides had no cross resistance with carbendazim, suggesting that they could be the first choice to control mango anthracnose.
In addition, the average EC50 and EC90 values of triadimefon, iprodione, tricyclazole and mancozeb were lower as compared to the other fungicides, and these fungicides could also be a choice to control mango anthracnose.
The selected isolates of C. gloeosporioides showed cross resistance among benzimidazole fungicides, between benzimidazole fungicides and diniconazole, among azoxystrobin, kresoxim-methyl and myclobutanil•kresoxim-methyl, among azoxystrobin, kresoxim-methyl and triadimefon, between difenoconazole and flusilazole•famoxadone.
Chlorothalonil had negative cross resistance with azoxystrobin, kresoxim-methyl and myclobutanil•kresoxim-methyl.
Hymexazol had negative cross resistance with azoxystrobin, kresoxim-methyl myclobutanil•kresoxim-methyl and triadimefon.
Therefore, these chosen fungicides are recommended for use to avoid the resistance of carbendazim-resistant C. gloeosporioides.
Download Adobe Acrobat Reader (free software to read PDF files)