Comparative effectiveness of some fungicides and salts applied preharvest or postharvest for controlling pear fruit rots.
El-Sheikh Aly, M. M.; Felaifel, M. S. A.; Fouad, N. A.; Badawy, H. M. A.;
Annals of Agricultural Science (Cairo) Year: 1998 Issue: Special Issue, Volume 1 Pages: 135-149 Ref: 15 ref.
1998
บทคัดย่อ
Six fungi (Botrytis cinerea, Penicillium expansum, Alternaria alternata, Mucor piriformis, Rhizopus stolonifer and Thielaviopsis paradoxa [Ceratocystis paradoxa]) were isolated from naturally infected pear (cv. Licont) fruits obtained from different orchards and markets at Menofeia Governorate, Egypt, during 1996. All isolated fungi were pathogenic to wounded fruits of Licont pear cultivar. In field tests with preharvest fungicides, Kaligreen (potassium hydrogen carbonate) at 800 and 1200 ppm was the most effective in reducing and suppressing decay caused by B. cinerea, P. expansum, A. alternata and M. piriformis, followed by Euparen (dichlofluanid) at 1200 ppm. When used as a postharvest fungicide at 1200 ppm, Kaligreen completely suppressed infection, followed by Tecto (thiabendazole) at the same concentration. Sorbic acid and chlorin were less effective in controlling fungal decay. Stored pear fruits covered with a single sheet of sodium metabisulphite were moderately protected from fungal de
cay, whereas, double sheets of sodium metabisulphite minimized fruit infection by B. cinerea and P. expansum and completely suppressed infection by A. alternata and M. piriformis. Fruits treated with sodium metabisulphite as a fumigant at 3.6 g/kg decreased infection by the test fungi. Preharvest treatment with calcium chloride at 6.0 g/L decreased the fungal decay of pear fruits, stored for 2 months at 5 deg C. In addition, calcium chloride used as a post-harvest treatment at the same concentration prevented infection by B. cinerea, A. alternata and M. piriformis and suppressed P. expansum. Preharvest treatment with calcium chloride at 6.0 g/L and Kaligreen at 1.5 g/L resulted in increasing firmness and increased total soluble solid content of Licont pear fruits, while titratable acidity was reduced.