الفهرس 
. MATERIALS AND METHODSOnly 14 pages are availabe for public view
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Abstract
Fennel (Foeniculum vulgare L) is considered as one of the
most important medicinal plants in the world. Fennel is attacked by
many fungal diseases cause considerable losses for producers. Soil
borne pathogens are considered as a major factor cause reduction in
fennel yield. Biological control, when properly implemented, is
usually more effective, durable and less in cost. Different biocontrol
agents belong to fungi, actinomycetes and bacteria were used to
evaluate their effects on controlling these pathogens. The present work
was designed to control pathogenic soil borne fungi attack fennel using
Trichoderma harzianum, Bacillus subtilis ,Streptomyces griseus(A1),
S. tendae (A2) and S. canescens (A3) isolates. Results show that all
treatments led to clear significant reduction in root rot disease
incidence compared with control treatment. Suitable date for adding
different antagonistic microorganisms were also studied , data
obtained show that adding any of used treatment before planting time
was more effective than adding the same treatment at planting or one
or two weeks after planting. Using different isolates of antagonists at
different concentrations, as seed coating, show positive correlation
between increase antagonists concentrations and efficacy of the
treatment. Adding antagonists as soil drench were better than adding
the same antagonists as seed coating.In field experiments the highest
yield was obtained when S. griseus (A1) was added before planting
time as soil drench. Root protection in fennel plants against root rot
pathogen was reflected on plant in form of increase, number of
inflorescences, weight of 100 seeds and total yield. Also, it was found
that adding S.griseus (A1) to fennel seeds as powder or soil drench led
to increase percentage of oil in fennel seeds and led to increase in
weight of 100 seeds. Organic agriculture provides substitutes for all
toxic fungicides are used in conventional agriculture. Biological
control agents are allowed according to European laws (EC 834 /
2007). We can suggest that production of T. harzianum, B. subtilis
,S.griseus(A1), S. tendae (A2) and S. canescens (A3) isolates on
commercial scale to be used to control fennel root rots disease under
field conditions in organic farms.
Key words: Fennel, Root rot, Biological control, Streptomyces spp. ,
Trichoderma harzianum, Bacillus subtilis , Fennel oil