PREFERENSI MAKAN LARVA Spodoptera Frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) DAN PERKEMBANGANNYA PADA SUMBER PAKAN BERBEDA

Dicky Wahyudi, Preferences Behaviour Of Spodoptera frugiperda (J.E. Smith)
(Lepidoptera: Noctuidae) Larvae and Their Development On Different Feed
Sources (supervised by Shahabuddin and Mohammad Yunus).
S. frugiperda J.E. Smith is an invasive pest and is a new pest on corn plants in
Indonesia, especially in Central Sulawesi. This pest is difficult to control and has
a wide host range not only on food crops but also on horticultural crops and
several types of animal feed grass, so it is necessary to control it in the form of
using plant species that have the potential to act as alternative hosts for S.
frugiperda. His research aims to determine the feeding preferences of larvae
towards different food sources, the percentage of leaf area eaten and the duration
of the stage and size of S. frugiperda. This research consisted of several stages,
namely rearing S. frugiperda, planting test feed, testing the feeding preferences of
S. frugiperda larvae, percentage of leaf area eaten, stage length and size of S.
frugiperda as well as the relationship between leaf trichome density and
percentage of leaf area eaten. The results showed that there were differences in the
feeding preferences of S. frugiperda larvae, with the feeding preferences in order
being Pakchong P. purpureum and P. sarmentosum and B. mulato. The percentage
of leaf area of food plants eaten by S. frugiperda larvae in the choice and nonchoice tests, namely in the choice test, respectively, were Pakchong (7.49%), P.
sarmentosum (5.38%), B. mulato (2.65%) and the lowest was P. purpureum
(2.43%), while in the non-choice test in order it was Z. mays (64.02%), P.
sarmentosum (40.95%), Pakchong (35.60%), P purpureum (35.16%) and the
lowest was B. mulato (21.46%). Observations of the stage length and size of S.
frugiperda started with instar 1, but many died so using larvae of instar 3. The
average stage length of S. frugiperda on different food sources, with the fastest
stage length being 21.08 days for Z. mays, 23.25 days in Pakchong, 24.50 days in
P. purpureum, 26.42 days in P. sarmentosum and 29.59 days in B. mulato. This
trend was also found in the size of S. frugiperda at each stage observed. The
highest density of leaf trichomes was in the food type B. mulato while the lowest
was in P. sarmentosum which does not have leaf trichomes and there was no
correlation between trichome density and the percentage of leaf area eaten. Based
on the phenol content, the highest total phenol (gGAE/g) was in P. sarmentosum
(60.30), followed by P. purpureum (56.60), B. mulato (35.10), Pakchong (25.90)
and lowest Z. mays (7.30).