اليات استحثاث المقاومة في نبات الخيار بواسطة Trichoderma harzianum وBacillus subtilis وGlomus mosseae اتجاه الفطر Rhizoctonia solani المسبب لمرض سقوط البادرات == Resistance Mechanisms In Cucumber Plant By Trichoderma Harzianum, Bacillus Subtilis And Glomus Mosseae Against Rhizoctonia Solani Causing Seedling Disease
Author name:
رباب مجيد عبد الذهيبي
Supervisor name:
علي هاشم الموسوي | هادي مهدي عبود
General topic:
Biology
Specific topic:
Plant
Degree:
Doctorate
University:
University of Baghdad - Ibn Al-Haytham College Of Education For Pure Sciences - Department Of Biology
Language:
Arabic
University location:
Baghdad
First pages:
24T2946 - p.pdf
Abstract:
نفذت هذه الدراسة للتحري عن اليات استحثاث المقاومة في نبات الخيار ضد الفطر الممرض Rhizoctonia solani بوساطة المعاملة بالعوامل الاحيائية وهي harzianum Trichodermaو Bacillus subtilis وGlomus mosseae وتاثير ذلك في نمو نبات الخيار وحاصله النامي تحت ظروف البيت | This study was carried out to investigate the mechanisms of induced resistance in cucumber plant against pathogenic fungus Rhizoctonia solani by bioeagent factors Tricoderma harzianum fungus, Basillus sibtilis bacteria and mycorrhizal fungus Glomus mosseae. The effect in parameters growth and yield of cucumber plant which growing under greenhouse and field conditions. The pathogenic fungus showed high Pathogenesis on cucumber plant. Three isolated of B. subtilis and T. harzianum showed high antagonism ability against R. solani under laboratory condition. For mycorrhizal fungus G. mosseae isolated was tested to study their ability in cucumber growth for chosen the best isolated which can used in anther experiment which results were as follows : - A - Pots experiment 1 - The bioeagent factors was showed their ability to induced several mechanisms of resistance in cucumber plant against pathogenic fungus R. solani, Which included increasing the activity of defense enzymes in existed of pathogenic fungus R. solani, The treatment (T. harzianum + G. mosseae) was recorded highest level in enzyme activity of Phenylalanine ammonia layase enzyme which was (25.3541) unit/gm fresh weight, While T. harzianum treatment showed significantly increased the enzyme activity of Polyphenol oxidase and Peroxidase which was (10.6707, 2.6137) unit/gm fresh weight respectively. This study showed no enzyme activity for chitinase enzyme excepted in some treatment and some periods.This study recorded increased in plant content of total phenol, lignin, salicylic acid hormone, total protein, The (G. mosseae + B. subtilis) treatment overtaken on other treatments in increased plant content of total phenol which was (1.989) mg/gm fresh weight, B. subtilis treatment was significantly increased plant content of lignin which was (18.318) mg/gm fresh weight, The treatment (T.harzianum+ B. subtilis) showed significantly increased plant content of salicylic acid hormone which was (1.8658) mg/gm fresh weight. This study recorded no Jasmonic acid hormone activity in treated plant except in some treatments but with low level, The treatment (G. mosseae + T.harzianum + B. subtilis) was recorded highest content in total protein which was (239.3) ?g/mg. 2 - The rate of seedling death and disease index was significantly reduced in bioeagent treatments, The lowest rate for seedling death in the treatment of (G. mosseae + B. subtilis), (G. mosseae + T.harzianum) and (G. mosseae + T.harzianum + B. subtilis) which were 11 % each for them comparison with control treatmentwith pathogen which was 100%.3 - The rate number of spores and percentage of mycorrhiza infection was significantly increased when mycorrhizal fungus G. mosseae interaction with T. harzianum or B. subtilis. The treatment of mycorrhiza infection with pathogen recorded highest number of mycorrhizal spores which was (1410) spore. The mycorrhiza infection reach to 100% in (G. mosseae + T.harzianum) and(G. mosseae + T.harzianum + B. subtilis) treatment with pathogen fungus. The treatment of (G. mosseae + T.harzianum) without pathogen recorded highest index of mycorrhiza infection which reach to (80)%, But the index of mycorrhiza infection and mycorrhizal root weight were decreased in the existed of pathogenic fungus, Mycorrhizal dependency it was increased in all treatments with pathogenic fungus and the treatment of (G. mosseae + B. subtilis) with pathogen recorded highest percentage in Mycorrhizal dependency which was (58.873)%. 4 - The plant content of chlorophyll (a, b, total) was significantly increased, The tratment of (G. mosseae + B. subtilis) with pathogen recorded highest level in chlorophyll a it was (5.30)mg/gm, the highest level in chlorophyll b found in(G. mosseae + T.harzianum + B. subtilis) without pathogen it was (6.07)mg/gm, (G. mosseae + T.harzianum + B. subtilis) treatment without pathogen recorded highest level in total chlorophyll it was (10.79)mg/gm. The concentration of phosphor concentration increased in shoot part of (G. mosseae + T.harzianum) without pathogen which was (0.538)%, potassium concentration were decreased in all treatments with pathogen excepted (G. mosseae + T.harzianum) treatment, The highest level of potassium in treatment of (B. subtilis) without pathogen which recorded (4.65)%, For nitrogen concentration was increased in all treatments with pathogen and the highest level in (T.harzianum) which was (5.114)%. Carbon concentration significantly decreased in all treatments with pathogen and (G. mosseae + B. subtilis) without pathogen recorded highest concentration in carbon which was (46.203)%. 5 - The result showed that all growth parameters either in the absence or presence of pathogenic fungus was significantly increased in all bioagent treatments.The percentage of germination reach to (100)% in (B. subtilis) with or without pathogen , the treatment (G. mosseae + B. subtilis) with pathogen recorded highest level in shoot length it was (92.40)cm, And the same treatment recorded highest rate in fresh and dry weight for shoot part which was (7.412, 0.990) gm respectively, (T.harzianum) without pathogen recorded highest rate in leaf area it was (453.083)cm2, The highest rate of flower number was in (T.harzianum) with pathogen which was (15.66)flower/plant. The fresh and dry weight for root, root length, root surface area and the rate of root diameter were significantly increased in comparison with control treatment without pathogen. The treatment of (G. mosseae + T.harzianum) without pathogen recorded highest level in fresh and dry weight for root which were (0.359, 0.094)gm respectively. Highest root length in (G. mosseae + B. subtilis) without pathogen it was (48.14)cm, root surface area decreased in the treatments with pathogen and the treatment (G. mosseae + T.harzianum + B. subtilis) without pathogen recorded highest root surface area it was (19.16)cm 2, The root diameter was increased in(G. mosseae) with pathogen was reach to (0.363)mm.B - Field experiment 1 - Under field condition the percentage of germination increased in the treatment without pathogen which were (94.44)% in treatments (G. mosseae) , (B. subtilis) and (G. mosseae + T.harzianum) respectively, In the treatments with pathogen the percentage of germination reduced and The bioeagent factors showed no reduction in percentage of disease infection or disease index with pathogenic fungi R. solani under field condition which reach to (100)%. 2 - The rate number of spores, percentage of mycorrhiza infection, index of mycorrhiza infection, mycorrhizal root weight and Mycorrhizal dependency on cucumber plant significantly increased when mycorrhizal fungus G. mosseae interaction with T. harzianum or B. subtilis. (G. mosseae + T.harzianum + B. subtilis) significantly overtaken on other treatments in increased rate of mycorrhizal spors it was (3950)spore, The mycorrhiza infection reach to (100)% in all treatments, For index of mycorrhiza infection the treatments of (G. mosseae + B. subtilis) and (G. mosseae + T.harzianum) recorded highest rate which reach to (100)%, (G. mosseae + T.harzianum + B. subtilis) treatment recorded high increased in mycorrhizal root weight and Mycorrhizal dependency which were (545.67 gm, 67.78%) respectively. 3 - The plant content of total chlorophyll was significantly increased, The highest level in(G. mosseae + T.harzianum + B. subtilis) treatment which was 5.19 mg/gm. There was significantly increased in the concentration of nutrition elements P, K, N, C in cucumber plant. The treatment (T.harzianum+ B. subtilis) recorded highest concentration in phosphor and nitrogen which were (489.4, 3.62) % respectively, The treatment of (G. mosseae + T.harzianum + B. subtilis) recorded highest concentration of potassium which was (2.975)%. The highest concentration of carbon recorded in B. subtilis treatment which was (34.823) %. 4 - All shoot, root and yield parameters of cucumber were significantly increased under field conditions. The treatment (T.harzianum+ B. subtilis) recorded significantly increased in plant height, dry shoot weight, leaf area rate number of flowers, rate number of fruit and fruit weight which were (42.87 cm, 10.85 gm, 631.06 cm2, 19, 17, 1275 gm) respectively. The treatment G. mosseae recorded significantly increased in fresh shoot weight which was (32.76) gm. The treatment with (T.harzianum+ B. subtilis) recorded significantly increased in fresh and dry weight of root, root length, root surface area, rate of root diameter, rate number of fruit and fruit weight which were (11.4 gm, 5.5 gm, 151.71 cm, 44.05 cm2, 0.763 mm, 17, 1275 gm) respectively,
