Abstract:
In this study, the nutritional indices of the larval stages of
Helicoverpa armig
era
(Hübner) were determined on 10 canola (
Brassica napus
L.) genotypes (Talaye, Opera,
Licord, Modena, SLM
046
, Hayula
420
, Zarfam, Okapi, RGS
003
and Sarigol) at 25
±
1
̊C,
60
±
5% RH and a photoperiod of 16: 8 (L: D) hours. The third instar larvae reared on
Talaye showed the highest value of Efficiency of Conversion of Ingested food
ECI
and
Efficiency of Conversion of Digested food
ECD
(7.005±0.632 and 8.972±1.862,
respect
ively). However, the lowest value of
ECI
and
ECD
was on Licord (0.503±0.017 and
2.507±0.449, respectively). The highest (0.778±0.091) and lowest (0.594±0.059) Relative
Growth Rate (RGR) of the fourth instar larvae were obtained on SLM
046
and Sarigol,
respe
ctively. Results indicated that the highest values of
ECI
and
ECD
for fourth instar
larvae were on Talaye (6.300±0.585 and 8.880±1.954, respectively). The lowest value of the
Relative Consumption Rate (RCR) and Approximate Digestibility (AD) of the fifth i
nstar
was recorded on Modena (5.193±0.629 and 38.625±11.340, respectively). The
ECI
and
ECD
values of the fifth larval instar were the highest on Talaye (9.893±0.889 and
19.655±0.966, respectively). The highest value of
RCR
and
AD
of the sixth instar was o
n
Okapi (7.781±0.665 and 82.223±1.922, respectively). Among different genotypes tested,
the highest
ECI
and
ECD
of the whole larval instars (12.323±0.310 and 32.357±5.508,
respectively) were observed on Talaye and the lowest ones (5.947±0.257 and 6.922±0.3
20,
respectively) were on Okapi. Together, Talaye and Okapi were the most suitable and
unsuitable genotypes, respectively, for
H. armigera
larvae
.
Keywords:
Approximate digestibility,
Brassica napus
, Digested food, Ingested food,
Relative growth rate.
