DETECTION OF SEEO ROT, ROOT ROT AND SEEDLING INFECTION...
DETECTION OF SEEO ROT, ROOT ROT AND SEEDLING INFECTION IN.
NATURALLY INFECTED COWPEA SEED IN SENEGAL AND THEIR CODNTROL
D. G. GAIKWk: D AND S. S. SOKHI *-ir
:. ‘\\ ;
-iL) . *
.:+..i.,<.~
.,:
I. S. R. A., C. N. ,R, A., B. P. 51, Bambey..(Senaal~,
West Africa y 64 “GL-l
,,
.~ II* I i
-,
Two varieties of cowpea namely Bambey 21 and 58-57 are cultivated in :, Senegal. by
the farmers but the stand of the trop in Bambey-21 remains very poor.
The ,studies
were, therefore, aimed :at pathogens attacking seed which resulted in seed rotlroot
rot/seedling infection and their control.
Seeds of these two varieties were collected from:’ CNRA,:- B&nb;ey& Seed
microflora was detected by rolled towel method. Fifty seeds were put ion.csets of
three blotter sheets prcviously moistened with water with four’ repiicatidns.’ The
sheets were rolled and Ikept at room temperature, (21.5%-375°C);
The,sheets were
opened after 10 days and observations were recorded. Bambey-2l was more prone
to infection of fungi causing seed rotlroot rot than 58-57. (Table l).; In Bambey-21,
TABLE 1. Control of seed rot,and root ro$*of cowpea by sec& tractme& <,
Variety
Seed treatment
Seed TOI
Healthy seed
Root rot
Organisms isolated from seed
Cungermi- (Germinated)
%
rot/ro& rot .
nated) %
%
Bambey-21
CoIltrol
61
23
‘16
?? Macrophomina phaseolina
(-Rhizoctonia bditicola)
*Fusacium 1 ‘equtse& &uaciun
sp. Pénicillium sp, itbizopus sp.
Erwiniasp. ” _ .
**Granox
16
a 4
0
.
.
(4 gkg)
Benomyl
24
76
0
(1 g/W
Thiram
35
50
15;
Macrophomina phastkna
(2 dkg)
58-57
Control
Il
89
0
Penicillium, Colletotrichum cap-
sici, Curvularia sp. and Erwinia
Granox
0
100
0
(4 h/kg)
Benomyl
0
100
0
(1 g/W
,.“‘.
. . . . *
.., . . . -ea‘ke‘“.r.~rr.
.<Lh.h..1*..s.1_._ ._
,. _. _._ew>-
.-.~
_ -..---
1 2 8
Plant Disease Research
seed dressing with fuugicides viz., Gtanox and Benomyl reduced these diseases more
effectively than .Thiram whereas in 58-57 a11 + these fungicides gave similar results
wifh equal efficacy probably due to the fact that in this variety seed was less
infected.
In earlier report (Sackston, 1969) from Senegal, Macrophomina phaseolina was
recorded in the cowpe,a seed and also considered the danger of transmitting the
pathogen from one area to another. Bambey-21 being more susceptible is likely to
endanger more’ of transmission of this pathogen.
Seeds of these viarieties were sown in the field on July 20, 1987 fo record the
incidence of Macrophomina ashy stem blight and it was recorded as 2% in Bambey-21
and no:infection in 58-57 when the trop was 2 weeks old.
At msturity the incidence
in Bambay-21 increaseld to 55 per cent and 25 per cent in 58-57 which shows 58-57
has resistance against &f. phaseolina. Some of the varieties are already known to
baye resistance to this disease (Khan and Bhatnagar, 1945; Mackie, 1934) and 58-57
cari @.utilizqd for breeding varieties resistant to this disease.. Dry seed treatment
with fungicides namely Bavistio,.Thiram, Captan and Benomyl are known to reduce
this disease (Sinha tind Khare,,.l977; Williams, 1975).
!
.<
I/
:.
Authors are thankful to CRSP of USAID from’ Michigan State University,
USA for funds and ISRA, Senegal for facilities.
:.
. Khan, A.R. end M.P. Bhatnagar, 1945. Indiun Fmg. 6 : 212-213.
Ma&ie, W.S. 1934. Phyiopathology 24 : 235.
Sackston, W.E. 1969. Plant Dis. Rep. 53 (6) : 438-439.
Sinha, O.K:and M.N. Khare. 1977. Indian Phytopath. 30 : 337-340.
Williams, R.J., 1975. III Biird. J. and K. Maramorosch. eds. Tropical diseases of Legumes, New York,
NY. Academic Press, 139-146.
NATURALLY INFECTED COWPEA SEED IN SENEGAL AND THEIR CODNTROL
D. G. GAIKWk: D AND S. S. SOKHI *-ir
:. ‘\\ ;
-iL) . *
.:+..i.,<.~
.,:
I. S. R. A., C. N. ,R, A., B. P. 51, Bambey..(Senaal~,
West Africa y 64 “GL-l
,,
.~ II* I i
-,
Two varieties of cowpea namely Bambey 21 and 58-57 are cultivated in :, Senegal. by
the farmers but the stand of the trop in Bambey-21 remains very poor.
The ,studies
were, therefore, aimed :at pathogens attacking seed which resulted in seed rotlroot
rot/seedling infection and their control.
Seeds of these two varieties were collected from:’ CNRA,:- B&nb;ey& Seed
microflora was detected by rolled towel method. Fifty seeds were put ion.csets of
three blotter sheets prcviously moistened with water with four’ repiicatidns.’ The
sheets were rolled and Ikept at room temperature, (21.5%-375°C);
The,sheets were
opened after 10 days and observations were recorded. Bambey-2l was more prone
to infection of fungi causing seed rotlroot rot than 58-57. (Table l).; In Bambey-21,
TABLE 1. Control of seed rot,and root ro$*of cowpea by sec& tractme& <,
Variety
Seed treatment
Seed TOI
Healthy seed
Root rot
Organisms isolated from seed
Cungermi- (Germinated)
%
rot/ro& rot .
nated) %
%
Bambey-21
CoIltrol
61
23
‘16
?? Macrophomina phaseolina
(-Rhizoctonia bditicola)
*Fusacium 1 ‘equtse& &uaciun
sp. Pénicillium sp, itbizopus sp.
Erwiniasp. ” _ .
**Granox
16
a 4
0
.
.
(4 gkg)
Benomyl
24
76
0
(1 g/W
Thiram
35
50
15;
Macrophomina phastkna
(2 dkg)
58-57
Control
Il
89
0
Penicillium, Colletotrichum cap-
sici, Curvularia sp. and Erwinia
Granox
0
100
0
(4 h/kg)
Benomyl
0
100
0
(1 g/W
,.“‘.
. . . . *
.., . . . -ea‘ke‘“.r.~rr.
.<Lh.h..1*..s.1_._ ._
,. _. _._ew>-
.-.~
_ -..---
1 2 8
Plant Disease Research
seed dressing with fuugicides viz., Gtanox and Benomyl reduced these diseases more
effectively than .Thiram whereas in 58-57 a11 + these fungicides gave similar results
wifh equal efficacy probably due to the fact that in this variety seed was less
infected.
In earlier report (Sackston, 1969) from Senegal, Macrophomina phaseolina was
recorded in the cowpe,a seed and also considered the danger of transmitting the
pathogen from one area to another. Bambey-21 being more susceptible is likely to
endanger more’ of transmission of this pathogen.
Seeds of these viarieties were sown in the field on July 20, 1987 fo record the
incidence of Macrophomina ashy stem blight and it was recorded as 2% in Bambey-21
and no:infection in 58-57 when the trop was 2 weeks old.
At msturity the incidence
in Bambay-21 increaseld to 55 per cent and 25 per cent in 58-57 which shows 58-57
has resistance against &f. phaseolina. Some of the varieties are already known to
baye resistance to this disease (Khan and Bhatnagar, 1945; Mackie, 1934) and 58-57
cari @.utilizqd for breeding varieties resistant to this disease.. Dry seed treatment
with fungicides namely Bavistio,.Thiram, Captan and Benomyl are known to reduce
this disease (Sinha tind Khare,,.l977; Williams, 1975).
!
.<
I/
:.
Authors are thankful to CRSP of USAID from’ Michigan State University,
USA for funds and ISRA, Senegal for facilities.
:.
. Khan, A.R. end M.P. Bhatnagar, 1945. Indiun Fmg. 6 : 212-213.
Ma&ie, W.S. 1934. Phyiopathology 24 : 235.
Sackston, W.E. 1969. Plant Dis. Rep. 53 (6) : 438-439.
Sinha, O.K:and M.N. Khare. 1977. Indian Phytopath. 30 : 337-340.
Williams, R.J., 1975. III Biird. J. and K. Maramorosch. eds. Tropical diseases of Legumes, New York,
NY. Academic Press, 139-146.