Abstract:
Recently invaded fall armyworm in Sri
Lanka has been regarded as a major maize pest
and became a crucial pest with substantial yield
losses. Management of the pest via sustainable
environmentally friendly measures is essential
and encourages rather than the usage of synthetic
chemicals. The latent resistivity of traditional
maize landraces, which are favoured by the Sri
Lankan farmers has not yet been investigated.
Thus, a laboratory experiment was designed to
investigate the leaf-feeding and oviposition
resistance of FAW in Sri Lankan maize landraces.
Eight local (OP) maize landraces (SEU02,
SEU06, SEU09, SEU14, SEU15, SEU16, and
SEU17) with comercial varieties (Bhadra and
GT722) were used. The feeding and oviposition
preference assays were conducted and revealed
that none of the accession showed complete
resistance to FAW feeding, but detected
differences in acceptance and preference with
varying degrees. Nevertheless, a significant
difference was observed in morphological traits
viz. leaf trichomes density and leaf thickness. The
Oviposition preference bioassay found that
Bhadra (χ2=5.4, df =1, p=0.02,12/3) reported
highly preferred by females as oviposition with the
high mean number of eggs (638.40 ± 4.20), while
SEU02, SUE06, SEU09, SEU10 and SEU17
(χ2=5.4, df=1, p=0.02, 3/12) reported with low
preference. Our study provides insight into the
density of trichomes on leaves does not seem to be
linked to larvae feeding preferences at later stages
of the larval phase.
