الفهرس | Only 14 pages are availabe for public view |
Abstract -The role of three beneficial rhizosphere microorganisms, i .e: Rhizobium leguminosarum, Bacillus megaterium var. phosphaticum and Trichoderma harzianum, either separately or in combination on the growth of three popular faba bean cultivaes, i. e. Sakha 1, Giza 3 Mohassan and Giza 716. was assessed. 1- In Vitro., experiment showed that there was no antagonistic effect between the three tested beneficial microorganisms. 2- Inhibition zone was observed between Fusarium solani and both of Bacillus megaterium and Rhizobium leguminosarum, however Trichoderma harzianum showed overgrowth on F. solani. 3-Inhibition zone was noticed only between Rhizoctonia solani and Rhizobium leguminosarum, however Bacillus megaterium and Trichoderma harzianum gave overgrowth result. 4-The rhizospheric microorganisms stimulated the emergence of faba bean seedlings both in time and numbers. The application of R. leguminosarum minimized the time of emergence to be 10, 11 and 14 days. B. megaterium induced emergence after 12, 12 and 14 days. T. harzianum resulted 12, 12 and 15 days. Combination of R. leguminosarum with either B. megaterium or T. harzianum resulted in the same effect for Sakha 1, Giza 3 Mohassan and Giza 716 cultivars. 5-The number of emerged and survived seedlings was not severly affected by the various tested rhizosphere microorganisms. The combination of R. leguminosarum+B. megaterium+T.harzianum increased Sakha 1 seedlings emergence. All the treatments caused either equal or higher seedlings emergence % for Giza 3 Mohassan except for R. leguminosarum which gave the lowest result. All the treatments caused more emergence % than the control except for the combination of the three tested microorganisms which gave the same result to the control. 6-The plant height of Sakha 1 cv. was increased significantly in response to all treatments up to 50 days. Combination between the microorganisms showed insignificant increase in the plant height. The treatment of B. megaterium+T. harzianum showed the highest plant height (31.6). All the treatments significantly increased the plant height of Giza 3 Mohassan than the control after 20, 30, 40 and 50 days after seeding whereas Giza 716 showed significant increase of the plant height than the control in most cases. 7-The leaves number of the three faba bean cultivars was about 4 leaves / plant after 20 days. The treatment of R. leguminosarum decreased the leaves number after 20 days. All the treatments increased the leaves number after 30, 40 and 50 days. 8-Sakha 1 cv. started flowering after 45 days in the treatments: control, R. leguminosarum and B. megaterium+T. harzianum. It started flowering after 40 days in the other treatments. All the treatments except for T. harzianum reduced the time of first flower appearance in Giza 3 Mohassan cv. Single application of any rhizosphere microorganisms didn’t affect the flowering date of Giza 716 cv., while any other combined treatments reduced the flowering date. |