International Journal of Horticulture, 2018, Vol.8, No.1, 1-7
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Table 1 Cummulative percentage mortality of
Callosobruchus maculatus
on cowpea seeds treated with different concentrations of
plant powders of
S. longepedunculata
Plant parts
Dosage (g)
Mean % mortality ±S.E.at 24 h to 96 h post treatment
24 h
48 h
72 h
96 h
Leaf
0.2
0.4
0.6
0.8
1.0
2.50±1.44
ab
6.25±1.25
bcd
6.25±1.25
bcd
6.25±1.25
bcd
10.00±2.04
cde
5.00±.00
ab
8.75±2.39
bc
8.75±2.39
bc
11.25±1.25
cd
13.75±1.25
cde
18.75±2.39
bc
26.25±3.14
cde
28.75±2.39
de
28.75±2.39
de
28.75±2.39
de
26.25±1.25
b
36.25±4.26
c
36.25±3.14
c
37.50±1.44
cd
46.25±3.75
de
Stem bark
0.2
0.4
0.6
0.8
1.0
8.75±1.25
cde
11.25±1.25
de
11.25±1.25
de
11.25±1.25
de
11.25±1.25
de
12.50±1.44
cd
12.50±1.44
cd
12.50±1.44
cd
16.25±1.25
def
16.25±3.14
def
20.00±2.88
bcd
21.25±3.75
bcde
25.00±2.04
bcde
26.25±3.14
cde
26.25±1.25
cde
51.25±2.39
e
61.25±3.75
fg
61.25±2.39
fg
62.50±4.33
g
65.00±3.53
g
Root bark
0.2
0.4
0.6
0.8
1.0
5.00±2.04
bc
8.75±2.39
cde
11.25±2.39
de
12.50±1.44
e
13.75±1.25
e
11.25±1.25
cd
18.75±2.39
ef
18.75±1.25
ef
18.75±2.39
ef
20.00±2.04
f
16.25±3.14
b
26.25±1.25
cde
30.00±3.53
e
30.00±4.56
e
40.00±3.53
f
52.50±4.33
ef
66.25±4.26
g
67.50±3.22
g
67.50±3.22
g
71.25±2.39
g
Control
0.0
0.00±.00
a
0.00±.00
a
0.00±.00
a
0.00±.00
a
Note: Each value is a mean ±standard error of three replicates. Values followed by the same alphabet are not significantly (p>0.05)
different from each other using Duncan’s Multiple Range Test
Table 2 Lethal dosage of
S. longepedunculata
powders require to achieve 50 and 95% mortality of
Callosobruchus maculatus
Treatment
Slope±S.E
Intercept±S.E
X
2
LD
50(FL)
LD
95(FL)
Sig.
Leaf
0.64±0.048
-0.521±0.044
824.829
6.52
(3.53-7.01)
9.45
(8.34-11.14)
0.0001
Stem bark
0.67±0.046
-0.542±0.044
97.60
5.42
(3.18-6.36)
7.98
(6.87-9.97)
0.0001
Root bark
0.64±0.048
-0.521±0.043
1320.456
3.17
(2.56-4.01)
5.68
(5.10-6.45)
0.0001
Note: S.E.: Standard Error, X
2
: Chi Square, LD: Lethal dosage, FL: Fidiciual limit
2.3 Effect of S.
longepedunculata
powders on oviposition and adult emergence by
C. maculatus
All the plant powders of
S. logepedunculata
tested in this study reduced the number of eggs laid by
C. maculatus
(Figure 1). Oviposition by
C. maculatus
was significantly lower (P<0.05) in powder-treated seeds than in
untreated (control) seeds. The highest number of eggs (162.25) was laid on control (untreated) seeds. The least
eggs (54.50, 58.75 and 70.75) were laid on cowpea seeds treated with root bark , stem bark and leaf at the highest
dosage of 5.0% w/w and it was significantly (P<0.05) different from other dosages of plant powders.
The highest percentage adult emergence (88.59%) was obtained on the control (untreated) seeds (Figure 2). The
least percentage adult emergence (27.52% and 29.78%) were obtained on cowpea seeds treated with the powders
of root bark and stem bark of
S. longepedunculata
at the treatment level of 5.0% w/w and it was significantly
different from other dosages of the plant powders.
