الفهرس 
Material and methodsOnly 14 pages are availabe for public view
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Abstract
Pod rot disease of peanut is a serious disease worldwide. it occurs on
fruits that develop below ground. Diseased plants do not have readily
visible aboveground symptoms. often the disease problem remains
unnoticed until the peanut is dug. In ARE Peanut areas are widely
increased with the increase of land reclamation.
Surveying studies were carried out on five peanut cultivars namely
Giza 4, Giza 5, local 383, Red race and While race, during season 1994, in
two governorates; Giza and Ismailia for percentage of natural occurrence of
pod rot diseaes and percentage occurrence of fungi associated with• shells
and seeds of different pod rot categories besides the apparently healthy one.
Eighteen cvs ,hybrids or lines were evaluated for their reaction to the
disease under field conditions during two successive seasons. Effect of
some field treatments i.e., fertilization, fungicidal combinations and three
growth substances on percentage of pod rot incidence and seed germination
of Giza 4 peanut cultivar under field conditions. Isolation frequencies of
various fungi on both shells and seeds were recorded with the different
categories. Seeds moisture and oil content, acid value, aflatoxins and other
mycotoxins were detected. Results obtained could be summarized as
follows:
I-Pod rot disease was recorded on the five surveyed cvs, in both
Giza and Ismailia governorates.
2- The cultivar, Red race was lower than the other cvs. in appearance
of disease categories on pods, in the two governorates surveyed.
3- Pods having general breakdown, was the most commonly spread
type of pod rot on cvs Giza 4 and Giza 5 with significant difference to the
other cvs in Giza and Ismailia.
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4- The category of pods having dry brown lesions appeared on all
cultivated cvs.
5- The lowest percentage of the disease was recorded on Red race
and the highest one was on Giza 5. Results also, indicated that the
percentage of pink discoloration was low on all cultivated cvs in both
governorates.
6-The percentage of pink discoloration was low on all cultivated cvs
in both govcrnoratcs.
7-Genera of Alternaria, Aspergillus, Cladosporium, Fusarium,
Penicillium, Pythium, Rhizopus, Sclerotium, and Trichoderma, besides
Rhioctonia solani, the most common fungi associated with pod rot of
peanut, were isolated from peanut pods and kernels, of peanut plants
cultivated in the two governorates surveyed.
8-The characteristic fungi of the three disease categories were
recorded on the related category. R. solani caused brown rot, F.
nunuliformc caused pink discoloration and various other pathogens caused
break-down, in the two governorates.
9-hlsariul/I spp. were forms characteristic of discolored shells
whereas S. rolfsii was constantly isolated from brown rot and general
breakdown, (’lado.\j)oriul/I spp. was constantly isolated from pink
discoloration, and Alternaria spp. was constantly isolated from general
breakdown, in the two governorates.
10- Genera of Aspergillus, Cladosporium, Penicillium, Pythium,
Rhizopus, Sclerotium, and Trichoderma, besides F. moniliforme, F.
oxysporum, F. solani; were isolated from both apparently healthy and
diseased categories, in the two governorates, Giza and Ismailia.
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II-Alternaria spp., Fusarium semitectum and Rhizoctonia solani;
were isolated only from diseased categories in the two governorates.
12- A. niger, F oxysporum, F. solani, Penicillium spp., S. bataticola
and S. rolfsii, were recorded on shell samples of the four categories, in the
two governorates.
13- A. flavus. was dominant in all seed samples, especially the
apparently healthy one, and was isolated from both shells and seeds
samples; of the four categories, in the two governorates.
14- Penicillium spp. followed by A. niger, and Penicillium spp.
followed by A. flavus, were the most frequent species isolated from shells
and seeds respectively in the two governorates.
15- S. bataticola, S. rolfsii, Penicillium spp. and Trichoderma spp.
were isolated from seeds of healthy pods (intact pods), and were dominant
in endocarpic community of sound mature peanut fruits.
16- S. rolfsii exhibited the highest percentage of pod rot infection
followed by F. oxysporum, on Giza 4 peanut cv in pathogenicity test
whereas, F OXYS[JO/’l”” followed by R. solani were more aggressive on
Giza 5 peanut cv. but F moniliforme was the lowest one, in this respect.
17- Varietal reaction revealed that pod rot diseases were spread on
all cultivars and the eighteen tested cultivars differed greatly ill their
reaction to the diseases, in both quality and quantity of pod rot incidence.
18- Under field conditions, addition of K alone, tended to increase
percentage of pods having dry brown lesions, and slightly affected
incidence of pink discolorations. At contrast, using P gradually reduced
pods with dry brown lesions and pink discoloration. Combinations of both;
clearly reduced the two categories.
19- The use of N only at the normal level; increased percentage of
pods having general breakdown.
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20- The highest percentage or apparently healthy pods, was recorded
with I’K combination or 45-48.
21- Combination of PK at levels 30-48 and 45-48 was the best
treatment on seed germination percentage of different pods categories,
except for pods having general breakdown.
22- PK fertilization increased Pacelomyces spp. and Penicillium spp.
111 both shells and seeds of all categories, whereas F. semitectum had
increased only in seeds of pods having dry brown lesions and Pythium spp.
in shells of pods having general breakdown. Besides, A. ochraceus, A.
terreus and Trichoderma spp. in both seeds and shells of pods having dry
brown lesions, A. flavus in seeds and Rhizopus spp., S. rolfsii and
Trichoderma spp. in shells of the same category.
23- Combinations of P and K; decreased A.flavus, A. niger in seeds
of apparently healthy pods and shells of pods having dry brown lesions, A.
flavus in seeds and shells of pods having pink discoloration, A. niger in
seeds of pods having dry brown lesions and pods having general
breakdown.
24- Addition of K increased R. solani in only seeds of pods having
dry brown lesions.
25- In shells of pods having general breakdown; PK nutnnon
increased A. nigel’, whereas A. tennis, A. flavus, Rhizopus spp., ,<{ rolfsii
were increased in both seeds and shells of this category.
26- In shells of apparently healthy pods; combinations of PK
increased A .flavus, A. niger, S. batatico!a and S. rolfsii.
27- Increasing P level increased average incidence of S. rolf vii in
shells and seeds of the four categories except for seeds of dry brown lesions
and of apparently healthy pods.
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28- Increasing K levels increased Pythium spp. but decreased S.
hataticola.
29- Moisture content of peanut seeds fluctuated within a wide range
as a result of fertilization with the normal level ofN and different levels of
P and K.
30- Oil content was greatly high in pods having dry brown lesions at
PK level 30-48 and the normal level of N, while the lowest one was
recorded on pods having general breakdown at PK level 30-0 and
fertilization with N at the normal level.
32-AII tested seed dressing fungicides effectively reduced the incidence
of pod rot and consequently increasing percentage of apparently healthy
pods.
33-l\llatoxin H. was detected in seeds of pods having pink
discoloration and pods with general breakdown which collected from
peanut plants treated with Nat normal level and PK at level 30-24.
34-Clear reduction was noticed on the acid value of seeds of
apparently healthy pods followed by pods with dry brown lesions as a
result of fertilization with the normal level ofN and different levels of P
and K.
35- Soil treatment with fungicides had also a good effect in reducing
the disease with highly significant differences compared with control.
36- Sumisclex was found to be the most effective one, as both seed
dressing and soil treatment, in reducing the disease and recording the
highest percentage of healthy pods.
37- Fungicidal application improved germination and generally
increased percentage of seed germination38- All fungicides applied; greatly reduced the percentage o,f fungi
isolated li’OI11 both shells and seeds of the lour categories, compared with
control, with few exceptions,
39- All fungicidal treatments clearly increased seed moisture content
than control treatment.
40- Fungicides treatments moderately affected oil content of
apparently healthy pods but greatly affected oil content in seeds of pods
having general breakdown and pods having dry brown lesions.
41- Fungicidal treatments increased the acid value of peanut oil,
compared with control. The lowest acid values were recorded on apparently
healthy pods, in most cases with Benlate followed by Sumisclex as seed
dressing.
42- All fungicidal treatments inhibited aflatoxins production, with
few exceptions on pods having dry brown lesions and pods having general
breakdown
43- 1\11 growth substances tested, great ly reduced pod rot of peanut.
IBI\ followed by I\TP, at 100 PPM were the best treatments iii increasing
percent of apparently healthy pods.
44- In all growth substances treatments, apparently healthy pod was
increased, parallel and proportional with increasing concentration.
45- ATP at 50 PPM was the best treatment in reducing pods having
dry brown lesions while, 100 PPM had better effect on pods having pink
discoloration.
46- IBA followed by ATP, at 100 PPM; were the best treatments in
reducing pods having general breakdown.
47- All growth substances treatments clearly increased percentage of
seed germination compared with control. ATP and IAA were better than
lBA. The highest percentage of seed germination on the four categories
was recorded with the concentration of 100 PPM.
48- Growth substances greatly affected occurrence percentage of
various fungi associated with both shells and seeds of the different
categories compared with control. .ln all treatments, fungi decreased with
incrcasing couccntrat ion.
49- Growth substances at concentration of 100 PPM exactly,
controlled all fungi associated with both shells and seeds of all categories
with few exceptions.
50- Growth substances at concentration of 25 PPM slightly affected
percentage occurrence of various fungi on shells and seeds of the four
categories.
51- Growth substances at different concentrations, had no consistent
trend on peanut seed moisture content of the different categories. The
highest percentage of moisture content was recorded on seeds of pods
having dry brown lesions whereas the least one was obtained on seeds of
pods having pink discoloration.
52- Generally ATP, lAA and lBA at concentration of 25 PPM,
reduced oil content, of all categories, with few exceptions. ATP at
concentration of 100 PPM raised oil content, of all categories except for
seeds from pods having general breakdown.
53- Growth substances at all treatments clearly increased the oil acid
value of seeds from both pods having dry brown lesions and healthy pods
compared with control.
54- Aflatoxin Bl was detected on seeds of pods having dry brown
lesions which collected from peanut plants treated with IAA at 50 PPM.
Aflatoxin B1 was detected on seeds of pods having general breakdown
previously treated with ATP at 100 ppm and lAA at 50 ppm. The allatoxin
type Gl was detected only in seeds of pods having general breakdown
previously treated with IAA at 50 ppm.
55- Ochratoxin A was detected III seeds of pods having general
breakdown previously treated with ATP at 25 PPM. Ochratoxin A was also
detected in seeds of pods having general breakdown where seeds were
treated with Topsin-M and cultivated in soil treated with Sumisclex. May
be this is the firs! report on the natural occurtancc of ochratoxin A on
peanut.