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العنوان
STUDIES ON SOME MEDICINAL PLANT
EXTRACTS FOR COMBATING MICROBIAL
INFECTION OF SOLANUM TUBEROSUM /
المؤلف
Nasr El-Din, Dina Gamal Abd El-Azeem.
هيئة الاعداد
باحث / دينا جمال عبدالعظيم نصرالدين
مشرف / طه عبد العظيم محمد عبد الرازق
مشرف / عزة محمد على
مناقش / محمد عماد عزب علي الفخراني
تاريخ النشر
2020.
عدد الصفحات
166 P. :
اللغة
الإنجليزية
الدرجة
ماجستير
التخصص
الزراعية والعلوم البيولوجية (المتنوعة)
تاريخ الإجازة
1/1/2020
مكان الإجازة
جامعة عين شمس - معهد البيئة - قسم العلوم البيئية الاساسية
الفهرس
Only 14 pages are availabe for public view

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Abstract

The potato plant is one of the members of the Solanaceae family and occupies an important position among food crops in many countries of the world. It is also in terms of nutritional value that is considered the first alternative to cereal crops in solving the food problem. It is the most important economic crop in terms of local consumption and export as well, and potato tubers become infected with many fungi and bacteria during harvest, storage and export, which leads to an increase in annual losses and adversely affects the volume of local production and exports.
1- In this study, We studied the effect of parts extract of some medicinal plants, such as leaves and oil extracts of Moringa oleifera, Oil extract of Simmondsia chinensis (jojoba) plant, and the effect of Imazalil as a fungicide In vivo and In vitro against eight pathogenic fungi and bacteria that infected to potato tubers as Alternaria solani, Fusarium solani, Helminthosporium solani, Rhizoctonia solani, Sclerotinia sclerotiorum, Ralstonia solanacearum, Erwinia carotovora and streptomyces scabies.
2- Isolation and identification occured in steps, Potato tuber samples were carefully washed in running tap water several times to remove adhering debris from the surfaces of potato tubers. Then, cut into small pieces, the epidermis of the infected tubers was removed by using a sterilized scalpel, and then small portions including the diseased and healthy inner parts of the tubers, sterilized in 70% ethyl alcohol for one minute, washed several times with sterilized distilled water and dried between two sterilized filter papers then transferred to Petri dishes containing potato dextrose agar (PDA) medium and incubated at 25°C for seven to ten days. were cut and cultured on (PDA) medium. After developing these microorganismis purified and identified.
3- The potato tubers used for virulence test were carefully selected on basis of size uniformity, sound and apparently healthy. selected tubers were washed with tap water, then surface sterilized with 70 % ethyl alcohol. Fungal cultures were prepared by growing each fungus in Petri dishes containing (PDA) medium, for 2 weeks at 25°C. Agar discs, 3 mm-diameter (inoculum disc), were prepared from the fungal cultures. Plugs of 3 mm-depth were removed from the surface of one side of each potato tuber using sterilized cork borer. Potato tubers were inoculated with Alternaria solani, Fusarium solani, Helminthosporium solani, Rhizoctonia solani, Sclerotinia sclerotiorum, Ralstonia solanacearum, Erwinia carotovora and streptomyces scabies isolates by inserting the fungal discs and bacterial disc right away into the opening of the tubers and the removed plugs were replaced. Potato tubers treated with sterile PDA medium 3 mm-diameter discs were used as a check. The inoculated tubers were immediately placed in sterilized jute bags and incubated at 25°C for 45 days. Three replicates, 9 tubers each, were prepared for each particular treatment. The pathogenic capability of isolates were measured by relating the percentage of rotten tissues diameter to the surface of the tuber after cross section obtained passing through the center of the infection site.
4- Isolation data revealed that 92 fungi isolates were isolated from naturally infected potato tubers which collected from some Egyptian governorates These fungal and bacterial isolates were causing the common potato tubers diseases where isolated samples which collected from six different Egyptian governorates.
5- These isolated microorganismis were identified as the most frequently isolated fungus and bacteria among the rest of isolates in all six inspected governorates. The highest number of isolated fungi (24 isolates) were recorded on potato tuber samples collected from Sharkia governorate, followed by (17 isolates) collected from Ismailiya governorate, the least number of isolated fungi (10 isolates) was recorded on samples collected from Beheira governorate.
6- Surveying indicate that 89 isolates of Bacteria including three i.e. Ralstonia solanacearum, Erwinia carotovoraand and Streptomyces scabies were isolated from naturally infected potato tubers which collected from some Egyptian governorates. The highest number of isolated Bacteria (27 and 25 isolates) were recorded on potato tuber samples collected from Beheira and Menoufiya governorate respectively, followed by (11 isolates) collected from Qalubia governorate, the least number of isolated Bacteria (8 isolates) was recorded on samples collected from all, Ismailiya and Sharkia governorate.
7- As for pathogenicity of isolates of pathogenic fungi and Bacteria, high severity (%) on potato tubers. Erwinia carotovora recorded the highest significant severity 100%, Ralstonia solanacearum recorded 94.44% and Sclerotinia sclerotiorum recorded 91.67% followed by Rhizoctonia solani, Fusarium solani, and Streptomyces scabies (88.89, 83.33 and 86.11%) respectively. While, the least significant severity recoded in Alternaria solani 75% and Helminthosporium solani 69.44%.
8- Results indicated that Control of Post-harvest diseases In vitro Moringa oleifera leaves extract as a medical and natural treatment , Imazalil fungicide as a chemical treatment gave high significant efficacy 100% at the third concentration and Moringa oleifera oil concentration at 2.5%. Generally, the treatments Moringa oleifera leaves extract, Moringa oleifera oil, Jojoba oil and Imazalil decreased the linear growth of Alternaria solani on PDA medium at all concentration compared with the control (90.0mm). Jojoba oil the least efficacy (24.2-71.33%) compared with the others three treatments.
9- As for controlling of Moringa oleifera leaves extract, Moringa oleifera oil gave high significant efficacy 100% at the third concentration and Imazalil fungicide as a chemical treatment at concentration 0.25%, While the effect of Jojoba oil decreased the linear growth of Fusarium solani to 30.2 mm with efficacy 66.44% in vitro at concentration 2.5 % compared with the control (90.0mm and 0.0%). Also, Effect of Moringa extracts and Jojoba oil compared with Imazalil against mycelial growth of Helminthosporium solani in vitro. Indicated that Moringa oleifera leaves extract recorded the highest significant effect 100%, the effect of Imazalil decreased the linear growth of Helminthosporium solani to 3.33 mm with efficacy 96.3%, Moringa oleifera oil (19.8mm and 78%) followed by Jojoba oil (23.2mm and 74.42%) at the fifth concentration compared with the control (90.0mm and 0.0%).
10- Effect of Moringa oleifera leaves extract as a natural antibacterial against Ralstonia solanacearum, Erwinia carotovora and Streptomyces scabies in vitro, where recorded completely inhibition the highest significant efficacy 100% at 30% concentration. Also, the same efficacy of Imazalil as a chemical treatment 100% at the first concentration against three bacteria. Followed by Moringa oleifera oil recorded completely inhibition to R. solanacearum, E. carotovora and S. scabies at 2.5% concentration. On the other hand, Jojoba oil was the least effective against R. solanacearum, E. carotovora and S. scabies recorded 38.9%, 27.8% and 57.4% respectively at 2.5% concentration. All tested concentration of treatment decreased gradually diameter of colonies compared with the control treatment.
11- Regarding the Control of Post-harvest diseases, In vivo Post-harvest treatments of the potato tubers (Solanum tuberosum L.) diseases with Moringa oleifera leaves extract , Moringa oleifera oil , Simmondsia chinensis (Jojoba) oil and Imazalil resulted in controlling significantly of disease in the naturally infected potato tubers during cold storage for 45 days, Diseases incidence of all treatments and the control showed high effectiveness of Moringa oleifera oil and Imazalil 100% followed by Moringa oleifera leaves extract and Jojoba oil 95.24% and 90.48% compared with the control. Also, Sprouting(%) of the naturally infected potato tubers recorded the least value 11% compared with the control 88.88%.
12- Artificial inoculation of the potato tubers with pathogenic fungi during cold storage for 45 days. Data resulted 89% disease severity in the control treatment of Sclerotinia sclerotiorum, Rhizoctonia solani followed by Fusarium solani, Alternaria solani and Helminthosporium solani (88.4%, 77% and 65.7%) respectively with the highest efficacy of Moringa oleifera oil and Imazalil then the others treatments against all of them.
13- Artificial inoculation of the potato tubers with pathogenic bacteria during cold storage for 45 days. Data resulted 100% disease severity in the control treatment of Erwinia carotovora followed by Ralstonia solanacearum and Streptomyces scabies (95% and 88%), with the highest significant efficacy of Moringa oleifera leaves extract 97% against Erwinia carotovora on artificial inoculated potato, while the high effect of Moringa oleifera oil 93% against Streptomyces scabie and the same efficacy of Moringa oleifera oil and Imazalil 88% against Ralstonia solanacearum.
14- Quality parameter to effect of post-harvest treatments on sprouting (%) of artificial inoculated potato with pathogenic fungi. where, recorded the least sprouting (%) with Simmondsia chinensis (Jojoba) oil, Moringa oleifera oil and Moringa oleifera leaves extracts except with Alternaria solani 66.66% compared with the control treatment. Also, recorded the least weight loss (%) with Moringa oleifera leaves extracts except with Fusarium solani recorded 4.9% ,Then Moringa oleifera oil except weight loss(%) of Sclerotinia sclerotiorum 4.6% compared with the highest weight loss(%) of control treatment for all tested pathogenic fungi.
15- Concerning the effect of post-harvest treatments on weight loss(%) of artificial inoculated potato with pathogenic bacteria. where, recorded the least weight loss(%) with Moringa oleifera oil, then Moringa oleifera leaves compared with the highest weight loss(%) of control treatment for all tested pathogenic bacteria and weight loss(%) of natural infected potato with tested pathogenes. where, recorded the least weight loss(%) with Moringa oleifera oil compared with the highest weight loss(%) of control treatment for all tested pathogenes.
16- Effect of post-harvest treatments on Firmness(N) of artificial inoculated potato tubers with pathogenic fungi Alternaria solani, Fusarium solani, Helminthosporium solani, Rhizoctonia solani and Sclerotinia sclerotiorum . where, increased Firmness(N) to treated tubers after harvesting with Moringa oleifera leaves extracts, Moringa oleifera oil, Simmondsia chinensis (Jojoba) oil and Imazalil during storage at 25°C for 45 days compared to untreated control. And with pathogenic bacteria Ralstonia solanacearum, Erwinia carotovora and streptomyces scabies. where, increased Firmness(N) to treated tubers after harvesting with Moringa oleifera leaves extracts, Moringa oleifera oil, Simmondsia chinensis (Jojoba) oil and Imazalil during storage at 25°C for 45 days compared to untreated control.
17- Effect of post-harvest treatments on Firmness(N) of natural infected potato with tested pathogenes Alternaria solani, Fusarium solani, Helminthosporium solani, Rhizoctonia solani and Sclerotinia sclerotiorum Ralstonia solanacearum, Erwinia carotovora and streptomyces scabies. where, increased or similar Firmness(N) to treated tubers after harvesting with Moringa oleifera leaves extracts, Moringa oleifera oil, Simmondsia chinensis (Jojoba) oil and Imazalil during storage at 25°C for 45 days compared to untreated control.