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Our present study was designed to investigate the role of both Trichoderma harzianum and chamomile (Matricaria chamomilla L.) flower extract in mutual reaction against growth of Pythium ultimum. In vitro, the activity of chamomile extract was found to reduce the radial growth of Pythium ultimum up to 30% compared to the control. Whereas, the radial growth reduction effect of T. harzianum against P. ultimum reached 81.6% after 120 h. Data also showed the productivity of total phenolics and total flavonoids by T. harzianum, was 12.18 and 6.33 mg QE/100 mL culture filtrate, respectively. However, these compounds were determined in chamomile flower extract at concentrations of 75.33 and 24.29 mg QE/100 mL, respectively. The fractionation of aqueous extract of chamomile flower using HPLC provided several polyphenolic compounds such as pyrogallol, myricetin, rosemarinic acid, catechol, p-coumaric acid, benzoic acid, chlorogenic acid and other minor compounds. In vivo, the potentiality of T. harzianum with chamomile flower extract against Pythium pathogen of bean was investigated. Data obtained showed a reduction in the percentage of rotted seed and infected seedling up to 28 and 8%, respectively. Whereas, the survival increased up to 64% compared to other ones. There was also a significant promotion in growth features, total chlorophyll, carotenoids, total polyphenols and flavonoids, polyphenol-oxidase and peroxidase enzymes compared to other ones. To the best of our knowledge, there are no reported studies that included the mutual association of fungus, T. harzianum with the extract taken from the chamomile flower against P. ultimum, either in vitro or in vivo. In conclusion, the application of both T. harzianum and/or M. chamomilla extracts in the control of bean Pythium pathogen showed significant results.

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Root rot caused by soil borne pathogenic fungi is the most sever disease attacks lupine plants. Isolation trials from diseased plants in some areas of Dakahlia Province (Egypt) was carried out. Rhizoctonia solani and Fusarium solani proved to be the most dominant isolates. Meanwhile, Fusarium oxysporum and Sclerotium rolfsii were less frequent. Efficacies of some plant resistance elicitors viz.: chitosan (CHI), Salicylic Acid (SA) and hydroquinone (HQ) in comparing to the fungicide Rhizolex T-50 as seed treatments showed significant reduction in the fungal growth in vitro. Chitosan at 8 g L(-1) and fungicide completely inhibited the growth of all isolated fungi, while SA at 1.4 g L(-1) and HQ at 1.2 g L(-1) inhibited the growth of Fusarium solani and F. oxysporum, respectively. The greenhouse experiments showed that S. rolfesii (No. 6) and R. solani (No. 2) followed by F. solani (No. 5) and F. oxysporum (No. 9) were the most aggressive root rot fungi. Soaking susceptible lupine seeds (Giza 1) in each one of the three selected elicitors showed a significant reduction in seedlings mortality. CHI at 8 g L(-1) was superior in increasing the percentage of healthy plants to record 72.5, 80.9, 62.7and 64.3%, when seeds were grown in soil infested with of F. solani, F. oxysporum, R. solani and S. rolfesii, respectively. These results were confirmed under field conditions in two different locations i.e., Tag El-Ezz and El-Serow Research Stations. CHI 8 g L(-1) proved to be the best elicitor after fungicide, in reducing lupine root rot disease. It showed 41 and 60% reduction in the plants mortality comparing to 56.37 and 69.13% in case of Rhizolex-T in Tag El-Ezz and El-Serow locations, respectively. The treatments were accompanied with a significant increase in lupine growth parameters, yield components and physiological aspects. Application of CHI at 8 g L(-1) or HQ at 1.2 g L(-1) was the most potent in this respect as compared to check treatment.

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