Page 49 - Volume 2,Issue 2, July 2009

© Benaki Phytopathological Institute
Sublethal effects of essential oils on Acanthoscelides obtectus 95
Adult longevity was not significantly affect-
ed (males: F3, 144 = 0.408, P > 0.05; females: F3,
101 = 1.647, P > 0.05), but the females surviving
the highest dose tested laid fewer eggs com-
pared to the control females (F3, 56 = 4.194, P
< 0.01). Egg hatchability was not significantly
affected (F3, 54 = 1.644; P > 0.05).
Exposure of pupae to eucalyptus essen-
tial oil vapours did not affect the develop-
mental time (males: F3, 207 = 1.31; females: F3,
195 = 0.389, all P > 0.05) or the weight of the
adult survivors (males: F3, 57 = 1.457; females:
Table 2. Developmental time (number of days from the end of exposure to adult emergence),
weight, longevity, fecundity and fertility of Acanthoscelides obtectus adults derived from pu-
pae that survived the exposure to three different doses of lavender essential oil vapours.
Dose
(μl/l air)
Mean developmental
time ± SE (days)
Mean adult weight
± SE (mg)
Mean adult longevity
± SE (days)
Mean number
of eggs laid
± SE
Mean (%)
unhatched
eggs ± SE
Males Females Males Females Males Females
0 6.8 ± 0.2a 7.5 ± 0.2a 5.23 ± 0.17a 6.41 ± 0.18a 15.6 ± 0.7a 22.6 ± 0.9a 53.9 ± 3.4a 10.5 ± 2.3a
21 7.4 ± 0.2a 7.5 ± 0.3a 4.94 ± 0.17a 6.11 ± 0.18a 14.5 ± 0.8a 19.5 ± 1.3b 43.3 ± 4.0ab 12.2 ± 1.8a
36.8 7.2 ± 0.2a 7.1 ± 0.2a 4.87 ± 0.12a 6.16 ± 0.22a 14.6 ± 0.6a 18.3 ± 0.9b 36.5 ± 4.8b 8.9 ± 1.3a
57.9 8.5 ± 0.4b 9.1 ± 0.5b 4.9 ± 0.19a 6.08 ± 0.18a 13.9 ± 0.9a 13.8 ± 0.9c 31.0 ± 8.3b 9.4 ± 1.2a
Means within a column followed by the same letter do not differ significantly (LSD test: P≥0.05).
Table 1. Developmental time (number of days from the end of exposure to adult emer-
gence), weight, longevity, fecundity and fertility of Acanthoscelides obtectus adults derived
from 2 nd instar larvae that survived the exposure to three different doses of lavender essen-
tial oil vapours.
Dose
(μl/l air)
Mean developmental
time ± SE1 (days)
Mean adult weight
± SE2 (mg)
Mean adult longevity
± SE2 (days)
Mean number
of eggs laid
± SE2
Mean (%)
unhutched
eggs ± SE2
Males Females Males Females Males Females
0 26.0 ± 0.3a 27.4 ± 0.2a 5.14 ± 0.12a 6.27 ± 0.72a 16.3 ± 0.8a 22.3 ± 0.8a 55.3 ± 2.8a 10.7 ± 1.7a
0.2 26.5 ± 0.3a 27.1 ± 0.3a 4.81 ± 0.11a 6.10 ± 0.10a 16.5 ± 0.8a 21.9 ± 0.8a 43.3 ± 3.4ab 17.5 ± 2.2a
1.4 27.4 ± 0.5ab 28.1 ± 0.6a 4.87 ± 0.13a 6.20 ± 0.14a 16.5 ± 1.0a 19.6 ± 1.0a 45.1 ± 5.2ab 12.8 ± 1.7a
2 28.4 ± 0.6b 28.7 ± 0.6a 4.84 ± 0.09a 5.91 ± 0.09a 14.6 ± 1.4a 17.8 ± 2.4a 33.9 ± 5.8b 11.0 ± 1.2a
Means within a column followed by the same letter do not differ significantly (1Mann-Whitney U test, 2LSD test:
P≥0.05).
Table 3. Developmental time (number of days from the end of exposure to adult emer-
gence), weight, longevity, fecundity and fertility of Acanthoscelides obtectus adults derived
from 2nd instar larvae that survived the exposure to three different doses of rosemary essen-
tial oil vapours.
Dose
(μl/l air)
Mean developmental
time ± SE1 (days)
Mean adult weight
± SE2 (mg)
Mean adult longevity
± SE2 (days)
Mean number
of eggs laid
± SE2
Mean (%)
unhatched
eggs ± SE2
Males Females Males Females Males Females
0 26.0 ± 0.3a 27.4 ± 0.2a 5.14 ± 0.12a 6.27 ± 0.72a 16.3 ± 0.8a 22.3 ± 0.8a 55.3 ± 2.8a 10.8 ± 1.7a
1.4 25.3 ± 0.7a 26.2 ± 0.6a 4.98 ± 0.14a 6.05 ± 0.09a 16.2 ± 1.1a 19.3 ± 1.2a 35.7 ± 5.3b 17.8 ± 6.2a
2.1 26.2 ± 0.5a 27.3 ± 0.3a 4.87 ± 0.07a 6.00 ± 0.10a 15.2 ± 1.0a 20.5 ± 1.4a 42.1 ± 2.9b 11.6 ± 2.0a
2.8 29.3 ± 0.9b 30.9 ± 0.9b 4.50 ± 0.13b 6.00 ± 0.25a 15.0 ± 1.9a 20.2 ± 2.4a 40.2 ± 5.3b 11.7 ± 1.2a
Means within a column followed by the same letter do not differ significantly (1Mann-Whitney U test, 2LSD test:
P≥0.05).