Water hyacinth (Eichhornia crassipes) is one of the most dangerous aquatic weeds for Lake Tana. To minimize invasion; biological, chemical and physical control methods can be used. Biological control based on the use of natural enemies of the weed to discourage its development was the best option. Plant pathogenic associated with naturally infected Faba bean by fungus was conducted at different sites with the objective of study the pathogen city indigenous fungi on water hyacinth to manage its spread on Lake Tana. Infected fungus plant samples were collected from three weredas (Amba Gyorgese, Dabat and Debarke) around Gondar at 20 Peasant association (PAs), The collection were done for infected Faba bean leaves and roots and isolated using Potato Dextrose Agar medium. Highest disease incidence per plant was recorded in water hyacinth plants using Using Modified Naseema et al. (2001) disease severity rating scale by inoculated with Rhizoctonia solani spp. Aspergillus flavus, Tricothcium roseum, Fusarium spp and Aspergillus niger show high moderate disease severity and tissue death at green house and pond level. Those fungus were released on September 2016 to prepared open pond at 16m 2 and water hyacinth was started severely attacked on November 2016, its disease incidence was 55% at 23˚C and humidity 39%, in December 2016 its disease incidence was 58.4% at humidity 31% and 23˚C, in January 2017 disease incidence was 65% at 26˚C and humidity 25% and in Feb 2017 not record disease incidence because all leaves are attacked and dry and Disease severity was 100%.However, in April 2017 due to the climate conditions becomes cold and rain the dried water hyacinth started make new shoot and at this time the disease severity was 90%. Some species of Fungi found in Faba bean leaf and root can eradicate the healthy water hyacinth at above 26˚C and at less than 25% Humidity.

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In Ethiopia, Oxytenanthera abyssinica A.Rich. Munro has varies economic importance. However, conventional propagation methods of O. abyssinica are generally inefficient due to their low multiplication rate, time consuming, labor intensive, and too costly. The objective of this study was to develop a protocol for mass micropropagation of O. abyssinica through seed culture. Murashige and Skoog (MS) medium augmented with 6-Benzylaminopurine (BAP) was used for shoot initiation and multiplication. For in vitro rooting, MS medium supplemented with 3-Indole –butric acid (IBA) was used. In shoot initiation experiment all viable seeds were proliferated in 5-7 days of culturing. In shoot multiplication at 0.004 g/L BAP was Sucssefuly shoot multiplied, also best root responding were found at 0.005 g/l IBA. The present optimized protocol enables for any acters who needs large numbers of low land bamboo seedling for industery, small and micro enterprize or for reafforestation programms.

Water hyacinth (Eichhornia crassipes) is one of the most dangerous aquatic weeds for LakeTana and other water body in Ethiopia. To reduce its invasion biological, chemical and physical control methods can be used. Use of natural biological enemies of the weed to discourage its propagation is one of the best recommended options by scientfic society.Among them, there are more fungi naturally a pathogen for water hyacinth and other plants. To use those patogenes to manage water hyacinth infestation in Lake Tana infected plant material by fungi were collected from three weredas (Amba Gyorgese, Dabat and Debarke) around Gondar at 20 Peasant associations (PAs) since Novmber 2015. The collection was done from infected Faba bean leaves and roots. All isolated fungus was attempted to infect the collected healthy water hyacinth in laboratory and green house. Among isolated fungus species Rhizoctonia solani, Aspergillus flatus, Tricothcium roseum, Fusarium spp and Aspergillus niger fungi show high moderate disease severity on the healthy water hyacinth at temporarey green house and laboratory. Disease severity scale was recorded using modified NAHEMA et al. (200). By following those experiments to show its efficiency, the effective pathogens on laboratory and green house were released to 16 m2open ponds since September 2016, in University of Gondar. In this study, we have recorded scientific data that shows the fungi were high potencial to attack healthy water hyacinth at above 26 oc and at less than 25 % humidity. From this research also we have observed the most infected water hyacinth by fungi have not produced flower and it can not re generate by seed in the next propagation sesaon.Finally, before directly release the fungi on Lake Tana its impacts were studied in the Goregora, at Kuame Michel kebela for a year in open ponds and in controlled wet land areas that not linked to the Lake by taking some common aquatic plants and fish from the Lake. Fortunatelly, those fungi have not impact on aquatic plant like Echinochloa and Cyperus papyrus grass, water quality and fish.