ANTIMICROBIAL AND PESTICIDAL POTENTIALITY OF ESSENTIAL OILS OF SOME MEDICINAL PLANTS AGAINST DETERIORATION OF CUMIN SEEDS
Fathia El-Shoraky, Nahed Rashed
Journal of Plant Protection and Pathology
This experiment was carried out at Sakha Agricultural Research Station from June 2011 to May 2012 to study the problem of reduction of cumin (Cuminum cyminum) seed germination. Cumin seeds were obtained from different sources for conducting the study. Several microbial species including sixteen fungal taxa, some yeasts and bacteria, were isolated from tested cumin seeds. The results exhibited suppressive of Fusarium spp. and Aspergillus in seed borne fungi. The most storage fungi which attack
... ored seeds led to decrease the germination percent. Ten essential oils plants (peppermint, eucalyptus, rosemary, nigella, caraway, thyme, marjoram, clove, double jasmine and celery) were used as seed coating materials in two forms, one as commercial and the other was as extraction. All oils used increased germination percent as comparing with vitavax except caraway and clove oils, in addition nigella oil proved to be the highest germination % (42.88%) comparing with 38.33% for the control . At the same time, caraway oil gave the lowest mean percent of germination (4.44%). The treated cumin seeds stored for one year maintaining it in petri dishes under room conditions and examination of seeds associated fungi and bacteria and germination after an equal period. Generally, germination percent increased with increasing the period of coating seeds with essential oils. All oils significantly reduced the percent of fungi associated the seeds especially Fusarium and Aspergillus. At the end of the storage period some of treatments were deteriorated and the other were observed at the healthy shape(seeds coating with caraway, celery, eucalyptus,double jasmine, thyme and rosemary oils). Oils of nigella; peppermint and eucalyptus inhibited Fusarium percent (100% reduction), while caraway oil inhibited Aspergillus (100% reduction). The bacterial infection inhibited by marjoram; peppermint; nigella and clove. The deterioration by insects suppressed by craway; celery; eucalyptus and jasmine treatments. The fungicidal and insecticidal effect of craway may occurs from the highly percent of carvon (61.58%) and limonene (29.11%). While, the bactericidal and insecticidal effect of marjoram oil may come from α-terpineol (35.4%). This work gives highlights on the potential of using essential oils as seed coating before storage for the pest managements.