Abstract:
Excessive use of agrochemical was one mechanism of increase crop production and which leads
to environmental damage. Microorganisms are important for agriculture in order to promote the
circulation of plant nutrients and reduce the need for chemical fertilizers. Today researchers are
able to repeatedly use them successfully in field experiments to increase growth and yields of
some crop and vegetables in different nations; however data on the effect of cyanobacteria on the
growth of rice, tomato and pepper seedlings is inadequate. The aim of this study was to isolate
and evaluate the effect of cyanobacteria on the growth of rice, tomato and pepper seedlings with
deferent cultivars. The study designs were randomized, purposeful laboratory based experiment.
Sediments sample used to isolate Bacillus and soil sample used to isolates Cyanobacteria were
collected randomly from Lake Tana and from Gondar Teacher Education Collage respectively.
The seeds of Peppers and Tomato were collected from Adet Agriculture Research Center and
Rice seeds from Woreta Rice Research Center. The seedling of pepper, rice and tomato were
prepared in University of Gondar, Biology department field experiment station. Pot experiments
in laboratory were conducted to evaluate the effect of Cyanobacteria and Bacillus on Rice,
Pepper and Tomatoes seedling. Five Bacillus and two Cyanobacteria species were isolated and
identified from Lake Tana and from Lake Tana and from Gondar Teacher Education Collage
respectively. All five Bacillus and tow Cyanobacterial isolates showed positive effects on the
growth of pepper, rice and tomato seedlings as compared to the control, however their
effectiveness varies from isolate to isolate and also from cultivar to cultivar. Among all
Cyanobacteria isolate (C1) was considered as having more plant growth promoting ability in all
cultivars of tomato Melkesalsa (70%, 70.4%), kochero (75%, 76%) and Miya (92.5%, 79%)
shoot length and root length respectively relative to other. In pepper plant cv. Endiam42 from all
isolates C1 provide more growth promotion with efficacy (80.73%,66. 72%) shoot length and
root length respectively and in cv. Markofana B4 was showed higher efficacacy(81.5%, 73.86%)
shoot length and root length respectively relative to other. In Rice cv. X-jigna and cv. Edget C2
showed higher growth promotion efficacy (37.93%, 50.53%) and (50.07%, 52.9%) respectively.
Thus, microorganisms could be considered as one of the possible biofertilizer that leads to
increase the health and vigor of seedlings. PGPR tests are recommended to be done on fields
how much increasing the yield of the crop and there should be demonstrated to the end users
who are having Agricultural importance.
Key Words: Bacillus, Cyanobacteria, Pepper, Rice, Tomato
