الفهرس 
Material and methodsOnly 14 pages are availabe for public view
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Abstract
SUMMARY
The present invcsligation was planned 10 stndy Some faetors affecting leaf
spols di<ease of Iaba bean CJlnsed by Ro.1ntis fllbae Sardo Slemphylillln botrYOSllIII
Wall. and Alfcl’Ilaria altcrllata (Fr.) Keissler .
The results could be summarized as follows:
(1) Isolalion and palhogenieity tests indicate that BolrY1is fabae Sard.,
Slemphylium bofryosum Wall. and Allern3l’ia allernala (Fr.) Ke/ssl
er
are the main
causals of Ieaf spots disease of Iaba bean lVicia faba I, Also, D. fabae was more
virulent than Stem. hoh’yosum and Alt. alte”naL, and the combination of the three
fungi was rnoro virulent than any of the three fungi alone.
(2) DotTyfis fabae gave its best rate of growth on leaf exh”act oCCaba bean
agar medium, while the lowest rate of gl”owth was on Brown’s medium whereas
Slem. bolryosmn grew well on Czapelc’s medium and ils Iowest rata of gl”Owth was
on Brown’s medium • Mt. allemala resembled Jl. fabae in ils gl”Owlh in the different
medln ,
(3) Leaf cxudates of healthy Ieaves of Gize 402 and Equadolce cvs, which are
morc susceptible to Il, fallae, cnhanced Spore germination and the rate oCgrowth of
B. fabae in vilro as eompared with the ””,udales of Giza 3 and Giza 2 cvs, the less
Susceptibles .
(4) Faba bean cultivars diffel”Cd in their reaction to D. fabae . The tested
eultivars were as follows: Giza 2 was mode ra le Suscepliblc, Giza 402 and Eqnadolce
were susceptible and Giza 3 was moderate resistant.
(5) TI,e growlh of II. fabae was completely hdJibited when Bavistin 50 and
Topsin M70 were added 10 polala dexl rose agar medium at the rate 10 ppm of their
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active ingredients whereas the fungicide Dithane M45 inhibited mycelial growth at
50 ppm. Also, thc growth of Stcm. botrvoSlllll was complctely inhibited with the
concentration 200 ppm for the fungicides Plantvax 20 Ec, Bavistin 50 and Dithane
M45 . \Vhcrcas, Dithano M 45 and Plantvax 20 Ec checked the growth of Alt.
alteinata at 100 and 200 ppm.
(6) Under greenhouse conditions all the tested fungicides Le Bavistin 50,
Topsin 1\170, Plantvax 20 Ee and Dithann M 45 were effective in reducing the
severity of leaf spots infection with n. labae .
Dithane 1\145 with concentrations 375, 250 and 125 I 100 L resulted in the
least infection with R. fabac after 60 days from inoculation on the two tested
cultivars Giza 2 and Giza 402 • In this respect, Plantvax 20 Ee followed by Topsin
1\1 70 were more effective than llavistin 50 • Also, increasing the tested
concentrations of all fungicides was in concomitant with the reduction in percentage
of spotted a reas .
(7) Plant length, No. of leaves, Fresh and dry weight of leaves were affected
with inoculation with n. fabae and Giza 402 cv, was the most effected one. Also,
the effcct of different fungicides ou plant length, No. of leaves and fresh and dry
weight of leaves differed according to the sensitivity of cultivars to the concentration
of fungicides and their effectiveness against B. fabae •
(8) The heaHhy leaves of both cuhivars i.e Giza 402 and Giza 2 conteued
nore tutal and reducing sugars than the diseased one • Spraying with fungicides
exhibitcd all illCI’CHSCin tutal mid J’cdudng slIgm’s in healthy plan’s cOlllpat’cd with
infectcd plants espccially in the susceptible cultlver Giza 402 •
(9) Frec and total phenols were produced and accumulated at a faster rate in
Giza 2 (moderate susceptible) than that of Giza 402 (susceptible) • As regards the
conjugated phenols, an apposite trend in both tested cvs. was 1I0ticed • Spraying
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with fungicides was not effective in increasing free and total phenols compared with
healthy leaves while the contrast was noticed in case of diseased leaves except in case
of Topsin 1\170 (150 g I 100 L) and Plantvax 20 Ec (100 mil 100 L) for Giza 2 and
Dithane M 45 (250 I 100 L) and Topsin M 70 (50 g I 100 L) for Giza 402 •
(10) Total free amino acids were higher in diseased leaves than in healthy
ones. Also, the susceptible cultivar Giza 402 contained higher levels of total free
amino acids than the moderate susceptible cv. Giza 2 • As regards, the effect of
spraying with fungicidcs, total free amino acids was differed with the different
treatments .
(11) In grccnh ouse experiments, foliar nutrients Foliar and FoIiaI’x (modified)
were the best in reducing disease severity.
(12) Number of leaves and fresh and dry weight were lower in the plants
that inoculated with I1. fahae compared with uninoculated ones. In this respect,
spraying with foliar nutrients exhibited an increase in the mean number of leaves
and dry weight for all nutrients whereas, the length of plants was not affected except
in case of spraying with Foliar x (modified) for Giza 3 cv. only.
(13) Spraying with foliar nutrients increased leaves content of total and
reducing sugars compared with unsprayed plants.
(14) Also, spraying with foliar nutrients showed an increase in total and free
phenols especially in case of spraying with X-Garden for Giza 3, Foliatrin or Foliar
x (modified) 1’01” Giza 402 and Foliatrin fur Equadolce cv. compared with unsprayed
plants.
(15) Spraying with Foliar x (modified) showed an Increase in the total free
amino acids for Giza 2, Giza 3 and Giza 402 whereas spraying with any of the other
nutrients exhibited a decrease ill them.
(16) Healthy leaves content of N, P and K was higher than that inoculated
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with H. fahae . Spraying with foliar nutrients exhibited an increase in the leaves
content of nitrogen especially in case of spraying with Foliar x (modified) and Foliar
x for Giza 2 and Equado1ce cvs, respectively . On the other hand, spraying with
foliar nutrients did not give a significant increase in leaves content of P and K •
(17) In field experiments, all fungicides under investigation decreased
significantly infection with leaf spot diseases than untreated plants. Dithane M 45
at the rate of 2.5% was the best of aU ill case of Giza 402 ill the first season only
and for Giza 3 cv in the two seasons. ”’hel”eas, Bavistin 50 at the rate of 0.1% was
the best in case of Giza 2 in the flrst season and Giza 402 in the second season.
Also, Topsin 1\1 70 at the rate of 0.1% was the best in the second season in case of
Giza 2 and Giza 3 cvs.. These fungicides also raised the yield of plants and the
weight of 100 seeds.
(18) Severity of infection with leaf spot diseases increased with the increasing
of sowing density. Less infection and good yield was obtained when sowing one seed
per hill at the two sides of the ridge at distance of 25 cm between bills.
(19) Also, in field experiments, addition of calcium superphosphate (P) and
potassium sulphate (K) generally reduced the percentage of infection than untreated
plants. Whereas, the addition of ammonium sulphate in the low level resulted in a
decrease in the percentage of infection compared with the high level (NJ • The
decrease in the disease severity coincided with an increase in the yield per plot and
the weight of 100 seeds.