الفهرس 
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Abstract
Plant disease control represents a major issue that farmers are facing in the management of cropping systems. Synthetic fungicides are currently used as primary means for controlling plant diseases. However, alternative control methods are needed to avoid the dangerous effects of chemicals.
Today, organic solid wastes must be treated, stored and used to avoid many types of problems. Several strategies of biocontrol agents of diseases caused by soil-borne plant pathogens have been developed based on the introduction of single or mixtures of biocontrol agents.
Natural products of plant origin have been used to control plant diseases. Compost, on the other hand, can offer an opportunity to serve as an ideal base for biocontrol. Compost tea is one of promised applications of compost, the enrichment/blending of the compost with plant products may convert composted material into a product of desired characteristics.
In vitro studies were carried out to evaluate the efficacy of some agricultural wastes (pomegranate peel powder extract, compost tea and compost with pomegranate peel tea) for their antifungal effect against two pathogens, i.e., R. solani and F. oxysporum .
Different results of inhibitory effect were obtained from the assay of plant extracts. The antimicrobial effect against the tested pathogens can be summarized as follow:
● All the examined types of aqueous pomegranate (Palestinian Sour Baladi, Palestinian Sweet Baladi and Egyptian Manfaloti) reduced the linear growth of F. oxysporum and R. solani with variable degrees. The extract of Palestinian Sweet Baladi pomegranate was resulted in the highest inhibition even at the two investigated concentrations. The maximum inhibition percent was recorded against F. oxysporum (62.0) at the concentration of 1g/100ml and for R. solani (54.67) at the same concentration.
● All the prepared compost teas as well as compost plus pomegranate teas using water and alkaline water inhibited the linear growth of the studied fungi with different degrees. On the other hand, the highest percent of inhibition against the two tested fungi was noticed for the tea prepared by the combination of compost with Palestinian Sour pomegranate type even with water or alkaline water. Inhibition percent recorded for F. oxysporum was 60.0 for that prepared by water and 61.0 for that prepared by alkaline water. While it was 45.3 and 70.0, respectively for R. solani. In addition, the majority of preparations using alkaline water recorded high inhibitory activity with significant differences than that prepared by water.
Accordingly, the Palestinian Sour pomegranate peels exhibited the highest significant percent of growth inhibition using alkaline water, therefore it was considered to be the most potent type. Consequently, further studies were done for in vivo evaluation of the capability of different combinations of the Palestinian Sour pomegranate peels with compost on suppression of damping off and wilt diseases of lupine in pot and field experiments. Different formulations of compost and peel powder were suggested for this evaluation, i.e., compost, compost with the selected botanical plant powder, compost tea, compost tea with the selected botanical plant extract and the aqueous extract of the selected botanical plant. The fungicide Rizolex-T was also investigated.
Pot experiments were conducted to evaluate the probable suppressive effect of the investigated treatments for protecting lupine plants against soil borne pathogenic fungi (R. solani and F. oxysporum), results demonstrated the following:
a. R. solani:
● All applied treatments either single or in combination have a positive effect and significantly reduced the incidence of pre- and post-emergence damping-off of lupine plants compared with the untreated infested soil. On the other hand, pronounced difference was observed for the survived plants between the mixture of compost with pomegranate peels powder and compost individually as well as with the mixture of compost plus pomegranate tea and compost tea alone, being in respective order 35.00, 30.00, 67.00 and 45.00%.
● The highest effective treatment was observed for compost plus pomegranate tea, where it recorded disease incidence as 29.00 and 4.00% pre- and post-emergence damping-off, respectively. This treatment also showed the highest percent of survived plants (67.0).
● A notable effect on nodulation status was concluded for the combined treatment compost plus pomegranate tea and Rizolex-T. The highest number of nodules/plant (13.7), dry weight of nodules (278 mg/plant), and nitrogenase activity (9.2 µmole/plant/hr.), was achieved for the chemical fungicide followed by the combined treatment compost plus pomegranate tea which recorded 12.7, 253.0 mg/plant, and 9.1 µmole/plant/hr. in the same respective order.
● The application of combined treatments mostly showed a significant increase in nodulation status over individual treatments. Dry weight of nodules treated with compost plus pomegranate peels powder showed significant difference over those treated with compost individually. On the other hand, application of the combined treatment compost plus pomegranate tea significantly increased nodules number, dry weight of nodules and nitrogenase activity, while treated plants with compost tea separately recorded the lowest values.
● The highest values of growth parameters were obtained due to application of compost plus pomegranate tea. The recorded values were 39 cm, 2.6 g/plant, 1.36 g/plant and 3.30 mg/g for plant height, shoot and root dry weight and chlorophyll content, respectively. The obtained results also illustrated that the combined treatments could be considered as most effective and induced significant increase in almost of the studied growth parameters compared with the individual ones.
b. F. oxysporum:
● All treatments under investigation induced a marked reduction in wilt percentage of lupine plants over those untreated infested plants. The compost plus pomegranate tea treatment exhibited the lowest percentage of wilt (20.0 ) and highest percentage of survived plants (80.0), next to the fungicide Rizolex-T, which recorded 13.33 and 86.67, in the same respective order, with no significant difference in survived plants percentage.
● The highest values of nodulation status and growth parameter were recorded with the chemical fungicide (Rizolex-T) followed by the botanical biocide (compost plus pomegranate tea) with no significant differences. The compost plus pomegranate tea treatment ranked as the most effective for improving nodules number, dry weight of nodules and nitrogenase activity.
The investigated compost amendments were evaluated for the control of damping-off and wilt diseases of lupine plant in a field trial naturally infested with F. oxysporum.
● Results illustrated that treatments of compost either alone or in combination found to be effective in decreasing wilt incidence, mostly differences among treatments were not statistically significant.
● The greatest reduction of disease incidence was achieved by the combination of compost with pomegranate tea, which recorded the highest percent of survived plants (91.0), highest values of all growth parameters (plant height, shoot and root dry weight and chlorophyll content), nodulation status (number and dry weight of nodules and nitrogenase activity), also the maximum accumulation of NPK in shoot and root tissues were recorded for this combination.
● Finally, it was obvious that all treatments performed significantly better than the untreated control in terms of recorded yield and its components in the field, while compost plus pomegranate tea ranked as the most effective treatment.