Abstract:
Reducing nitrogen status of floriculture plants is
an effective tactic in pest management
by decreasing host plant quality. Life table parame
ters and population growth rate of
Aphis craccivora
(Hemiptera: Aphidiae), as well as cosmetic and qual
itative parameters
losses associated with aphid infestation were evalu
ated in relation to N fertilization levels
on
Gomphrena globosa
, under greenhouse condition. Four N fertilization
levels (0, 30, 60,
and 100%
of recommended 2 kg m
-3
) were used. The results indicated that aphid’s
intrinsic rate of natural increase on plants fertil
ized with 100%
of the recommended N
level was the highest. Abundance and population gro
wth rate of aphid also positively
correlated with N fertilization levels. The interac
tive effect of aphid population and N
fertility significantly affected growth parameters
of the plants. In the absence of aphid,
plant yield improved linearly with increasing N lev
els. However, aphid population highly
decreased shoot to root ratio and the number of flo
wers in plants fertilized with 100%
of
the recommended N level. According to our findings,
fine-tuning fertility to reduce
A.
craccivora
population is a steadfast tactic to produce market
able globe amaranth
ornamental plant.
Keywords:
Aphid performance,
Aphis craccivora
,
Nitrogen fertilization, Plant yield,
Population growth.
