الفهرس 
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Abstract
Sugarcane cultivations are affected by a number of fungal
diseases; among these is Pokkah boeng which is caused by a fungus;
Fusarium moniliformis var. Plant defensins and chaitinases are
produced by Plants to protect them against fungal infection. Defensins
are small cysteine-rich peptides which belong to a group of
pathogenasis-related defense mechanism proteins. These proteins inhibit
the growth of a broad range of microbes and are highly stable under
extreme environmental stresses. Chitinases are endoglucanase enzymes
that cleave the internal β-1,4-N-acetyl-D-glucos-amine linkages in
chitin polymers; the major component of the cell wall of fungi. The
plant vector pMON22653 harboring defensin (def1) gene derived from
Medicago sativa, under the control of the CaMV 35S promoter and the
plant vector pGL2 that harbors a class I rice chitinase gene (chi11)
under the control of the CaMV 35S promoter and a hygromycin
resistant gene as a plant selectable marker were used to transform
sugarcane explants to develop plants resistant to Pokkah boeng. The
fusarium-susceptible sugarcane cultivars C9 and PH were used to
establish a regeneration system for sugarcane. For its high regenerabilty;
C9 was further selected to develop transgenic sugarcane. Leaf disks
were used as explants and transformation was performed using the
biolistic delivery system. Transformation and transcription of transgenes
were confirmed by Southern hybridizations and reverse-transcription
PCR (RT-PCR). Greenhouse bioassay was performed on the transgenic
pants by challenging with a vigorous isolate of the fungal pathogen Fusarium moniliformis var. The level of fungal infectivity was
determined using RT-PCR with specific primers. Transgenic lines were
more resistant to infection by fusarium than the control plants. Results
indicated that plants overexpressing defensin conferring a better
resistance to fungal pathogens than these overexpressing chitinase.
Nevertheless, expression of both chitinase (chi11) and defensin (def1)
genes into sugarcane plants acquired them antifungal resistance against
fusarium infection.