الفهرس 
Material and methodsOnly 14 pages are availabe for public view
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Abstract
SUMMARY
This work was aimed to study the f ac tors influencing
the severity of root rot disease of peanut and method of
control. The causal organisms were isolated from different
lOCalities in A.R.E., identified and the patnogenicity was
determined. The susceptability of different peanut varieties
to the disease was evaluated. The effect of organic and
inorganic manuring and ~hizobi~ inoculation on plant growth,
disease severity and nittogen fixation was determined. The
effect of different systemic and non-systemic fungicides on
growth of pathogens, plant growth, nitrogen fixation and
disease severity was investigated. Moreover, the effect of
these fungicides on the soil and rhizoshpere microflora Was
studied.
The results might be summarized as follows:
1. The fungi lihizoctonia sOlani (Kuhn), Sclerotium
rolfsii, Rhizoctoni.a bataticola (Taub.) Butl., F-usarium
0x’y’sporum(Sohlech tendahl) and .EgsaritynBolani (Martius)
were pathogenic to peanut causing root rot disease. li. solgni
was superior in this respect than §. rolfsii while the other
fungi were of low importance.
2. The local tested varieties were susceptible to
infeotion”with root rot disease organisms but Giza (3)
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va.riety was less suceptible to infection as compar ed with
the other tested varieties.
3. Soil infestation with lie solan~ increased root rot
disease and decreased the numbers, dry weight, size of
nodules and total nitrogen content and dry weight of
plants.
4. Inoculation with Rhizobium c~re resulted in a
decrease in the percentage of disease peanut plants. It
increased the numbers, dry weight and size of nodules,
also dry weight of plants and total nitrogen content pet
plant. Organic manure gave the same results.
5. It Was found that nitrogen fertilization increased
the inQidence of disease, numbers, dry weight, size of
nodules, dry weight of plants and total nitrogen content ..
6. Soil infestation with g,. solani and .2• .t:0lfsii
alone or combined increased the percentage of pre-, postemergence
damping-off and root rot disease. However, it
decreased the nitrogen content. It also reduced the number,
fresh and dry weight of nodules and fresh and dry weight of
roots and shoots.
7. Inoculation with Rhizobiu-m.-. in soil infested with
the pathogens resulted in a decrease in the pre-, poatemergence
damping-off and root rot disease percentages.
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While it increased the numbers, fresh and dry weight of
nodules. It also increased the fresh and dry weight of
plants and total nitrogen content.
8. Counts of total microbial flora in the soil were
lower than in the rhizosphere. Rhizosphere/Soil ratio (R/S
ratio) was high in the vegetative growth period. Fungicidal
treatment decreased the total microbial flora density.
9. Actinomycetes counts were low at the beginning of
the experiment but increased as the plant grew up. ActinomYcetes
counts in the soil were higher than those obtained
in the rhizosphere except in the case of the un-inoculated
soil treated with fungicides where higher count was observed.
R!S ratios for this grouP were negative and also quite law.
Fungicides differ~d in their effectiveness on actinomycetes
eouat.
10. The count of fungi was higher in the control than in
rhizosphere soil treated with fungicides especiallY in the
vegetative stage. At the flowering and maturity stages a
low count of fungi was observed.
11. The fungicides Bavistin and vitavaxlCaptan were the
most effective fungicideS in inhibiting the growth of lie
solani while vitavaxlCaptan and vitavaxlThiram were the most
effective in inh1biting tne growth of -S. .rolfeii. The other
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fungicides inhibited the growth of the pathogens at varying
degrees.
12. Sclerotial formation of R-. -801-an-i waS completely
inhibited at low concentrations of Benlate and Brassicol.
Sclerotia of -S. -ro-lfsii were not formed at 5 ppm of Vitavax/
Captan and 10 ppm of Vitavax/Thiram.
13. Treating seeds with fungicides reduced the percentage
of pre- and post-emergence damping-off and root rot
disease in the field. The most effective fungicides were
found to be Benl.a te , Vitavax/Th1ram and Vitavax/Captant
respectively.
14. Tre ating soil with fungic ides reduced the percentages
of pre-, post-emergence damping-off and root rot
disease. Brassicol-75 and Orthocide-75 were the most
effective.
SUMMARY
Field experiments were conducted at Sids Agricultural
Research Station, Beni Suef Governorate for two growing
summer seasons (1988 and 1989). Experiments were designed
to study the effect of planting dates and irrigation
intervals on the growth and yield characteristics of different
types of fodder cowpea seeds. The studied factors were:
A- Planting dates (main plots):
Early, (first-May) common (mid- May) and late (first-
June.) sowings .
B- Irrigation intervals (sub- plots)
Irrigation at 10, 15, and 20 days intervals of
2930, 2680 and 2320 m3j feddan, respectively.
c- Seed type of Cowpea (sub- sub- plots) :
Small blackish, large spotted, and mixed seed types.
A split split plot experimental design with four
replicates was used haVing the applied factors randomly
located as indicated above.
Results can be summarized as follows:
A- Vegetative growth characterstics
1- Height of plants:
Seeding fodder cowpea at the common date (mid- May)
produced the tallest plants. Also, earlier sowing (first-
----- . --_._--~ - _. - ----- ----
-- - .._ .. - --_. -- --’”--_ ... --- -- -- --’-’--.
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May) was significantly favourable in producing taller plants
than late (first- June) sowing.
Height of fodder cowpea plants reduced significantly
as the applied irrigation intervals increased from 10 to 15
on the
blackish
and up to 20- day.
Small blackish seed type produced sfgnificantly taller
plants as compared with the large spotted seed type.
The interaction effect of the applied three factors
height of plants was significant. Sowing small
seed type on the common date using the shortest
irrigation interval produced the tallest fodder cowpea
plants.
2- Leaf areal plant
The response of this studied character to the applied
factors was almost similar to the height of plants presented
above.
The highest leaf area was obtained at the common
seeding date for the small blackish seed type irrigated at
the shortest interval with significant interaction effect in
the two seasons. Also. each of the applied factors exhibited
a significant effect on leaf areal plant.
3- Leaf area index
Leaf area index was significantly higher in common
seeding date as compared with either early (May 1st). or
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late (June. 1st) sowings. It is also higher for small
blackish seed type than for the large spotted seed type with
significant differences in the two seasons. Fodder cowpea
leaf area index decreased continuously in the two seasons as
the irrigation intervals increased from 10- to 15- and 20-
day with significant differences. The int~raction effect of
the three applied factors on this studied character was
also- significant in the two seasons .
4- Number of leaves/ plant:
Number of leaves / plant of fodder cowpea decreased
from common to early then late sowing dates with significant
differences in the two seasons. Also, the highest number of
leaves! plant was for the small blackish seed types as
compared with the large spotted one significantly. Meanwhile
number of leaves! plant increased continuously and significantly
as the irrigation intervals decreased from 20- to 15-
and to 10-day. The interaction effect of the applied factors
I
on this character was significant in the two seasons.
5- Number of branches! plant:
The highest number of branches/ plant of fodder cowpea
wa·s significant ly obtained at the early sowing as compared
- -- ------_ .._---------
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with either common or late sowings, where there is no significant
difference in between for the two last two dates.
Results were true in the two seasons.
A significant reduction in the number of branches/
plant was obtained at the longest irrigation intervals as
compared with any of the other shorter irrigation intervals,
where there was no significant difference in between.
No significant difference in the number of branches /
plant whether using small blackish or the large spotted seed
type of fodder cowpea in the two growing seasons.
Also, no significant interaction effect of the applied
factors on the number of branches} plant was obtained in the
two seasons.
/
6- Leaf/ branches ratio:
Late sowing of fodder cowpea significantly produced
the lowest leaf/ branch ratio as compared with either the
early or common sowing date in the two seasons. Whereas.
common sowing date produced significantly higher leaf/
branch ratio than early- sowing only in the second season.
The highest leaf/ branch ratio was obtained at the
shortest irrigation interval in the two seasons. However,
significant and continuous reductions in leaf/ branch ratio
was obtained in the two seasons as irrigation intervals
increased from 10 to 15 and up to 20- day intervals.
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Small blackish fodder cowpa type produced slightly
but significantly higher leafl branch ratio as compared
with the large spotted seed type of the two seasons.
The interaction effect of the applied factors on the
ledf/ branch ratio was significant in the two seasons.
B- Yield Parameters
7- Forage yield:
Results proved that the total forage yield of fodder
cowpea was affected by the applied factors in a similar way
(,
as that of the first and second cuts.
Common seeding date (mid- May) was the optimum sowing
date for producing the highest forage yield. This was
followed by the early then the late sowing with significant
differences in the two seasons.
Forage yield was decreased continuously and significantly
as the irrigation intervals increased from 10- to 15-
and 20- day intervals. The highest forage yield was
obtained at the shortest irrigation interval.
Small blackish seed type of fodder cowpea was significantly
higher in forage yield production as compared with
the large spotted seed type. So it could be recommended that
the small blackish seed type of fodder cowpea is of high
potentiality in forage yield production as a summer leguminous
forage crop.
--- -- - -- ._”.- ._.
I
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Interaction effect of the applied three factors on
the forage yield-was significant. Such results were true in
the two growing seasons.
8- Seed yield:
Seed yield of fodder cowpea was coritinuously decreased
as seeding was delayed from early to common and late
seeding with significant differences in the two seasons. The
highest seed yield was obtained at the shortest irrigation
interval. As irrigation intervals increased. seed yield
decreased significantly.
Seed yield was not significantly affected by the
grown seed type of fodder cowpea in the first season .
However. in the second season. small blackish seed type
produced slightly but significantly higher seed yield than
large spotted seed type. Mixed seed type gave the higest
seed yield.
The interaction effect of the applied three factors
on the obtained seed yield of fodder cowpea was significant
irrthe second season but not in the first one.
9- Seed index:
Late seeding significantly reduced the seed index as
compared with either early or common seeding dates. Whereas.
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there was no significant differences in the obtaineJ seed
index for the earlier two seeding dates in the two seasons.
No significant difference in the obtained seed inde~
due to the applied irrigation intervals in the two seasons ..
Seed index of the obtained large spotted seed t y p..
was slightly but significantly higher than that of t~e small
blackish seed type.
The interaction effect of the three applied f ac L...
on the seed index was significant in the two seasons.
10- straw yield:
The highest straw yield was obtained at the ear-Iy
sowing. Delayed sowing to the cornman or late sowing < i gui >
ficantly decreased straw yield in the two seasons. Also.
straw yield increased significantly by decreasing ll!.!~
irrigation intervals from 20- to 15- and to 10- day ill th~
two seasons.
straw yield of the small blackish seed type of fodder
cowpea was higher than that of large spotted seed ty~e witll
significant difference.
Significant interaction effect of the ]- appl led [”ctors
on the straw yield was obtained for the two growing
seasons.
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11- Biological yield:
A continuous and significant decrease in the
biological yield was obtained as sowing date was delay. i
from early to common and up to late sowing. Biological yield
was continuously and significantly increased as the
irrigation intervals decreased to 10- day interval. 1.11
addition, bioglogical yield of fodder cowpea was si gn if i car.:
tly higher for the small blackish seed type as compared’.’!th
the large spotted seed type. These results were true fer Lh’
two growing seasons.