基本HTML版本
International Journal of Horticulture 2014, Vol.4, No.17, 1
-
6
http://ijh.biopublisher.ca
2
been reported to be safe and promising in the
protection of crops (Jilani et al., 1988).
Several products from the plant kingdom have been
evaluated and noted for their effectiveness in the
management of insect pests (Oni, 2014). Lale (2001)
also suggested that plant derived insecticides could be
a better replacement for the synthetic insecticides in
stored products protection. Vegetable oils, essential
oils, crude extracts, powders and other products from
plant have been tested against
C. maculatus
(Lale,
1995; Boeke et al., 2001). Effective control of the
cowpea seed beetle in storage with powder of parts of
many indigenous plants when applied at 2% of the
weight of stored beans has been well documented
(Adedire and Lajide, 2001; Ofuya and Salami, 2002).
Botanical insecticides are naturally occurring insecticides
that are derived from plants, they possess repellent
and or deterrent properties and are environment
friendly (Isman 2000; Ayvas et al., 2009). Therefore,
in this study insecticidal effects of powder from the
leaf of
H. suaveolens
(L.) was evaluated for the
management of
C. maculatus
(F.) on Oloyin and Ife
brown varieties of cowpea,
V. unguiculata
Walp.
Results
The effects of the powder on adult mortality revealed
that significantly more adult died with higher doses of
the powder. The powder exerts insecticidal effect on
the
C. maculatus
over the 3days of exposure. Treated
seeds of oloyin cowpea had higher number of
C.
maculatus
killed compared with the untreated and was
significantly different at p<0.05 (Table 1). Result
obtained for mortality on ife-brown cowpea in Table 2,
was similar to that in Table 1. Seeds treated with 0.3g
of the powder consistently had highest number of
killed adults which was different statistically from
those of the untreated seeds (p<0.05). This revealed
insecticidal properties of the powder of hyptis on the
exposed adults. Table 3 showed the effects of the
powder on the bionomics of the beetle insect.
Treatment significantly reduced oviposition and adult
emergence both of which were significantly different
(p<0.05) from the untreated seeds. Least number of
eggs was laid and fewer adults emerged from the
seeds treated with the powder at 0.3g. Highest number
of seeds with eggs was obtained from the untreated
seeds and was statistically different from those of the
treated at p<0.05. Similar observation was also made
for the number of seeds without eggs.
The results obtained for the ife-brown cowpea seeds
treated with the powder were similar to the result for
oloyin cowpea in Table 3. All the parameters
measured differ significantly at p<0.05. Significantly
reduced oviposition, number of emerged adults and
seeds with eggs were recorded on seeds treated with
0.3g of the powder. Though, no significant difference
exist among the treatments for the number of seeds
without eggs differences exist between the treated and
untreated which was significant at p<0.05 (Table 4).
Table 1 Mortality of
Callosobruchus maculatus
on Oloyin after 24, 48 and 72hours after treatment application
Varieties
Concentrations (g)
24 Hours
48 Hours
72 Hours
Oloyin
0.05
0.1
0.2
0.3
0.0
0.88b
0.88b
1.23a
1.17a
0.00c
0.71b
0.88b
0.71b
1.27a
0.00c
0.88b
1.06ab
1.06ab
1.53a
0.00c
Note: *: Means followed by the same letter in same column for each parameter are not significantly different from each other by
DMRT at 5% level of probability
Table 2 Mortality of
Callosobruchus maculatus
on Ife-brown at 24, 48 and 72hours after treatment application
Varieties
Concentrations (g)
24 Hours
48 Hours
72 Hours
Ifebrown
0.05
0.1
0.2
0.3
0.0
1.39a
1.17b
1.29b
1.46a
0.00c
1.23a
1.17b
1.09b
1.46a
0.00c
1.17b
1.44a
1.23b
1.68a
0.00c
Note: *: Means followed by the same letter in same column for each parameter are not significantly different from each other by
DMRT at 5% level of probability