Study On The Screening Of Attenuated Strains And Mechanism For Fusarium Oxysporiumf. Sp. Cucumeris After Treated With Parsley Rotten Root And Rhizophere

The study on Fusarium oxysporiumf. sp. cucumeris treated with parsley distilled water, acetone and ethanol extracts from rotten root and rhizophere respectively and then use the extracts effect the Fusarium oxysporiumf. sp. cucumeris at one generation. We will subculture more generations in medium conditions until to the6generation. We measured the pathogen’s colony diameter and field pathogenicity among different treatment for each generation. Furthermore, in order to screening attenuated strains of Fusarium oxysporiumf. sp. cucumeris of parsley different extracts from rotten root and rhizophere, the defensive enzyme activity and pathogen’s fusarium acid content and its enzyme activity of CWDEs for different treatment each generation were determined. The key results were as follows:1. We treated Fusarium oxysporiumf. sp. cucumeris with parsley distilled water, acetone and ethanol extracts from rotten root and rhizophere respectively. Different treatment showed the1st generation colony diameter of Fusarium oxysporiumf. sp. cucumeris had the strongest inhibitive effect, and following inhibition weaken with the increase of the subculture generation. Three parsley extracts from rotten root and rhizophere had attenuation effect on virulence of Fusarium oxysporiumf. sp. cucumeris, disease index of all of the different treatment were first reduce, then increase with the increase subculture generations. Different treatment strain was inoculated to the6th generation, the disease index of parsley distilled water, acetone and ethanol extracts from rotten root was38.67%,37.83%and32.00%,respectively. The disease index of parsley distilled water, acetone and ethanol extracts from rotten root rhizophere was39.50%,44.50%and36.17%, respectively. The study failed to screened attenuated strains of Fusarium oxysporiumf. sp.cucumeris in treated with three parsley extracts from rotten root and rhizophere respectively one generation.2.The different treatment of parsley distilled water, acetone and ethanol extracts from rotten root rhizophere one generation processing were first reduce, then increase of fusarium acid content and CWDEs activity dur the1-6generation of Fusarium oxysporiumf. sp.cucumeris. Compare with the blank treatment, the fusarium acid content of parsley distilled water, acetone and ethanol extracts from rotten root was 4.44%—20.62%,8.37%—28.28%and6.92%—26.82%, respectively. The fusarium acid content of parsley distilled water, acetone and ethanol extracts from rotten root rhizophere was3.31%—23.16%,2.89%—21.26%and7.23%—27.33%, respectively. The pectinase, cellulose activity and β—glucosidase activity of parsley distilled water, acetone and ethanol extracts from rotten root compared with blank treatment were decrease4.86%,3.81%,2.54%;54.98%,40.12%,24.69%and15.15%,11.61%,6.78%, respectively. The pectinase, cellulose activity and β—lucosidase activity of parsley distilled water, acetone and ethanol extracts from rotten root rhizopheret compared with blank treatment were decrease3.03%,5.71%,3.88%;64.04%,62.50%,37.42%and9.78%,17.77%,15.03%, respectively. During the experiment, the lower fusarium acid content and CWDEs activity regard as a new auxiliary condition.3. Determine the POD, SOD, CAT with the different treatment of parsley distilled water, acetone and ethanol extracts from rotten root rhizophere one generation and subcultured to6generation. It is show that the activity which were treated with parsley distilled water, acetone and ethanol extracts from rotten root of POD, SOD, CAT from1st28.27%,25.13%,31.73%;52.93%,47.83%,56.67%and6.47%,6.50%,6.32%to10.20%,6.73%,8.47%;9.04%,12.64%,8.72%and4.44%,3.52%,5.50%in the6th. The POD, SOD, CAT of parsley distilled water, acetone and ethanol extracts from rotten root rhizophere drop from37.53%,34.00%,32.73%;51.42%,46.93%,48.72%and6.58%,6.83%,7.21%to10.87%,8.07%,9.13%;13.01%,11.51%,17.62%and4.48%,5.27%,4.22%.