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العنوان
Bio-Potential of Compost Tea Produced from Agricultural and Municipal Solid Wastes to Reduce Disease Incidence of Plant Fungal Pathogens /
المؤلف
Elsaiid, Gehan Abd Elmonaim Elbaz.
هيئة الاعداد
مشرف / Gehan Abd Elmonaim Elbaz Elsaiid
مشرف / Mehreshan Taha EL-Mokadem
مشرف / Atef Fathalla Mohamed Abdel-Wahab
مشرف / Ehab Ali D. Sarhan
تاريخ النشر
2019.
عدد الصفحات
351 P. :
اللغة
الإنجليزية
الدرجة
الدكتوراه
التخصص
الزراعية والعلوم البيولوجية (المتنوعة)
تاريخ الإجازة
1/1/2019
مكان الإجازة
جامعة عين شمس - كلية البنات - قسم النبات
الفهرس
Only 14 pages are availabe for public view

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Abstract

The extensive use of chemical fertilizers and pesticides in agriculture is currently under debate due to environmental concern and fear for consumer’s health. Because there is no substitute for chemical control alone as fungicides in reducing plant diseases, promising alternatives of biological control were be done by great numbers of investigators .Our study designed to evaluate two types of compost; one from Agricultural Residues (AR) and the other from Municipal Solid wastes (MSW)enriched with olive pomace and bioagents as biological control fertilizer in order to minimize the environmental pollution by chemical fertilizers and/or the accumulation and burning the agricultural wastes. Therefore, the present study was conducted to evaluate the efficacy of this combination for controlling lentil root-rot and wilt pathogenic fungi (Fusarium oxysporum and Rhizoctonia solani).
Compost prepared from different organic wastes differ in their nutrient contents, chemical, and biological properties as well as in their quality and stability, so before their application in the field, its nutritional value and possible negative effects were assessed through microbiologic and agronomic testing in order to protect the environment and humans from any harmful substances it may contain in order to be suitable for agricultural and horticultural uses. The results were compared with international standards in order to verify that the compost is identical global and local specifications and to verify the quality of the finished compost.
The obtained results from laboratory, pot and field experiments could be summarized in the following:
• Physical properties (color, odor, bulk density, and water holding capacity) of both types of compost under study were within the recommended standard. Both types of compost samples appeared dark brown in color with an earthy smell reflect the compost maturity.
• Chemicals analyses (pH , EC, organic carbon % , organic matter %, macronutrients, and NH4+-N and No3--N were within the recommended dose except for EC of MSW which did not coincide within these limits and this may be attributed to the variation in the feedstock .
• Regarding available phosphorus and potassium, content in both types of compost were within the suggested reference for available potassium, while both types of compost were higher than the minimum suggested reference range for available phosphorus.
• Concerning heavy metals (Zn, Cu, Ni, Cd, Pb, Co and Cr); it was found that their content in the Agricultural residues compost (AR) were lower than the regulation limits prescribed by three different international standard; EPA, British Columbia and CCME (Class A), for exceptional quality compost and can be used for all types of applications.
• In case of MSW compost, the concentration of Cu, Zn and Cr were well below the critical limits, while in case of Pb, Ni, Cd, and Co, their values exceeded the critical limit specified by EPA, British Columbia and CCME (Class A), but were below the critical limits prescribed by CCME (Class B) and according to CCME guidelines this type must be restricted in use.
• Regarding available micronutrients (Fe,Mn, Cu, and Zn)data showed that their values were higher in MSW than AR compost.
• Cation exchange capacity which had been studied as a potential indicator of compost maturity, both AR and MSW exceeded the minimum recommended value for mature compost.
• The obtained results show a relatively high microbial population for AR and MSW compost; bacterial and actinomycetes population size and diversity were nearly the same for both types of compost, while in case of fungi, AR compost exhibited higher content of fungi than MSW compost.
• The absence of E.coli, shigella, and salmonella in both types of compost was corroborated which is compliant with the sanitation requirements for safe application of compost in agriculture.
• Data of dehydrogenase activity recorded 120.77µg TPF/ g dry weights for AR compost while recorded 119.74 µg TPF/ g dry weights for MSW .
• Concerning the physical , chemical and biological parameters of maturity and stability indices of compost (color, odor, C/N ratio, PH under anaerobic condition at 550C,NH4+/ NO3- ratio , sorption capacity index and the overall Co2- evolution) were within the recommended standard which indicate that both types of compost were mature and stabilized .
• Germination Index (GI) values attained using different types of seeds for both types of compost exceeded 80% as an indication of phytotoxin-free compost and consequently safe for soil application.
• The humification characteristics of AR and MSW compost were within the recommended standard and reflect the maturity and stability of the tested composts.
• The Average Compost Quality Index (CQI) equation values obtained for both types of compost indicated that Agriculture residues compost (9.24) to be extremely good quality, while Municipal solid wastes compost (3.50) represent moderate quality.
• Analysis of Olive Pomace (OP) applied in this study emphasize that it is very rich in organic matter, phenolic compounds, and possess considerable amounts of mineral nutrients such as nitrogen, phosphorus, potassium, sodium, calcium, and magnesium, and a wide range of micronutrients such as iron, copper, manganese, and zinc.
• Olive Pomace (OP) is very rich with microbial population, this is clear from the total count of bacteria and fungi and from dehydrogenase activity, on the other hand, the OP is free from pathogens.
• Concerning the phytotoxicity of Olive Pomace (OP), it was found that by increasing the concentration from (10 % to 50 %), the germination percentage of cress and barley drastically decreased.
• Enrichment of both types of compost; AR and MSW with OP (10%) the germination percentage recorded100% in both (cress and barley) seeds by AR+OP compost, while recorded 98.7% and 100% for cress and barley seeds respectively by MSW+OP compost.
• Enrichment of composts with OP increased their nutrients content and micronutrients levels with their values are within the recommended standard reference, except for phosphorus content, their values decrease after enrichment with olive pomace but both compost still recording higher values than the minimum suggested reference range (50-120 ppm) for available phosphorus as recommended.
• In vitro experiment, results revealed that all tested Aerated Compost Teas (ACT) exhibited significant inhibition of mycelial growth of R. solani and F. oxysporum compared to control. Enrichment of compost with both Olive Pomace (OP) and bioagents mixture (BA), were the most effective treatment against R. solani and F. oxysporum
• The fungicide Rhizolex-T at a concentration (5ppm) completely inhibited the mycelia growth of R. solani in vitro test, while inhibited F. oxysporum at concentration 100 ppm.
• SEM of tested pathogen mycelium removed from the confrontation zone showed aberrant morphology such as shrinkage, curling, mycelium asymmetry, partial distortions and lysis of fungal mycelium.
• In pot experiments, all treatments decreased the pre- and post-emergence damping-off and increased the percentage of survived plants.
• Compost tea enriched with OP and bioagents treatment significantly exhibited a lower percentage of pre-emergence damping-off and highest percentage of survived plants compared to other treatments.
• Application of different compost teas treatments, as well as Rhizolex-T, significantly improved the vegetative growth parameters and nodulation status of lentil plants grown under field conditions.
• The lentil plants treated with compost tea plus OP and bioagents recorded the maximum number and dry weight of nodules, plant height, shoot and root dry weight, chlorophyll content and number of branches after 75 days of planting compared to control.
• Compost teas tested treatments significantly increased shoot and root NPK of lentil plants grown under field conditions compared to control. The highest contents of the shoot and root NPK were measured for lentil plants treated with compost tea plus OP and bioagents.
• The application of different compost teas treatment and Rhizolex-T significantly improved lentil yield components i.e., plant height, number of pods/plant, seed weights/plant, number of seeds/plant, one thousand seeds weight, seed protein compared to untreated control.
• The treatment of compost tea enriched with OP and bioagents recorded the maximum values for pods/plant, seed weights/plant, number of seeds/plant, one thousand seeds weight, seed protein compared to untreated control.
• The antagonistic effects of the different treatments were associated with a marked increase in pathogenesis related proteins (PRP) expression and a decrease of disease severity; different treatments resulted in induction of 13 novels PR-protein not detected in untreated control.