Effects of culture filtrate medium of Colletotrichum gloeosporioides (Penz) Sacc. on cell structure phenomena of onion (Allium cepa L.)
1995
Kanya Wongviset
Study on properties of Czapek filtrate medium after the culture of Colletotrichum gloeosporioides (Penz.) Sacc. fungus, the pathogen of twister disease of onion, revealed an IAA-like substance activity. The Rf value of paper chromatography was 0.52-0.54, which was the same Rf value of standard IAA. One directional thin-layer chromatography in different 7 solvent mixtures showed also an IAA-like substance activity at Rf 0.35, 0.56, 0.94, 0.71, 0.48, 0 and 0.20 which corresponded to the Rf value of standard IAA 0.35, 0.58, 0.49, 0.71, 0.48, 0 and 0.20, respectively. Moreover, IAA-like substance was also recorded by high performance liquid chromatography at retention time 18.4 min. It can be concluded that the fungi can produce IAA-like substance in Czapek medium. Furthermore, the fungi grown in Czapek medium comprising 200 ppm tryptophan synthesized more IAA-like substance than in those medium in the absent of tryptophan. The maximum content of this IAA-like substance was detected in 14 days. However, in comparing to the culture filtrate from medium without tryptophan, 200 ppm standard tryptophan and 200-400 ppm standard IAA, the culture filtrate from medium containing 200 ppm tryptophan caused an abnormal symtomps of elongation and twisting of young leaf in 7 days. Histological study represented that wall and nucleus of cell around injected areas were degraded significantly. The use of 100, 500 and 1000 ppm, 20 micro L of triiodobenzoic acid (TIBA) and 100, 500, 1000 ppm, 20 micro L sodium fluoride (NaF) onto infected plants reduced IAA-like substance content, but they can not inhibit the disorder of the plants.
显示更多 [+] 显示较少 [-]