An Improved Method of Seed Health Testing for Detecting the Lurked Seed-borne Fungi of Fenugreek

摘要

An improved method of seed health testing was developed to detect lurked pathogens on fenugreek which coexist in low percentage. Blotting papers were soaked in solutions of NaOH and KOH 0.3 and 0.2 M, respectively instead of tap water which is used in standard blotter and deep freezing method. Thirty two samples of fenugreek seed collected from Egyptian commercial market were examined. Using 400 seeds of each sample, 25 seeds were distributed on 3 layers of blotting paper soaked in 0.3 M NaOH or 0.2 M KOH in 9 cm diameter sterilized Petri dishes. A comparable set was kept in which sterile water was used as control. The dishes were incubated at 20±2 for 7 days under cool white fluorescent light with alternating cycles of 12 h light and 12 h darkness as recommended by ISTA. KOH and NaOH treatments respectively showed the presence of 6.5 and 7.5% of Verticillium dahliae as compared to 0.3% in the standard blotter and 1% in the deep-freezing method. KOH treatment also showed the presence of Fusarium moniliforme and F. solani which were detected at 5.4 and 0.7% compared to 0.5 and 0.2% in the standard blotter method and 2.9, 0.4%, in the deep freezing method, respectively. Sodium hydroxide stimulated the growth of F. semitectum and Curvularia sp., which were detected at 1.4 and 0.7%, respectively as compared to SBM and DFB which showed the presence of 0.3 and 0% in case of SBM and 0.5 and 0.3% in case of DFB. No difference was observed in different treatments for detecting Cercospora traversiana .