The Brazilian
Cerrado presents a great variety of Lepidoptera species;
however, information concerning their larvae plant hosts
lacks. The present work was developed at Área de Relevante
Interesse Ecológico (ARIE) – Cerrado Pé-de-Gigante, located in
Santa Rita do Passa Quatro, SP, Brazil, where several
lepidoptera species can be found, mainly the Oecophoridae,
Pyralidae, Riodinidae, Lycaenidae, Notoctuidae, Tortricidae
and Gelechiidae families. Various species build shelters using
leaves where larvae end their life cycles. One of the
objectives of this work was to study the relations between
herbivory by lepidoptera leaf rollers and the total contents
of nitrogen, water and tannins in the leaves of Byrsonima
intermedia (Malpighiaceae). The larval food preference and
its relation to leaf nutritional quality was determined in
bioassays. The research shows that immature leaves inside the
rolls present a low concentration of tannins (14% dw) compared
to immature leaves totally exposed to sunlight (40% dw), but
there were no differences in water or nitrogen content between
these leaf groups. The results of the bioassays using
Cerconata achantina showed that larvae prefer immature
leaves (15 to 30 days old) exposed to less than 5% of total
light incidence inside roll condition rather than those
exposed to total light incidence outside roll condition. The
herbivory level in immature leaves inside the rolls was more
than 50% while in leaves outside the rolls, it was less than
5%. The results from lepidoptera leaf rollers show that these
leaf shelters increase the leaf nutritional quality inside the
rolls, which is related to the low content of tannins,
compounds considered as defenses against insects since they
cause protein precipitation. The rolls can also provide
protection against desiccation, predators and parasites.
Index terms:
nutritional preference, Oecophoridae, tannin, bioassays,
nutritional quality, immature leaves, shelter, Cerrado
Copyright:
The copyrights of this original work belong to the authors
(see right-most box in title table). This abstract appeared
in Session 13 – INSECT PHISIOLOGY, NEUROSCIENCES, IMMUNITY
AND CELL BIOLOGY Symposium and Poster Session, ABSTRACT BOOK
II – XXI-International Congress of Entomology, Brazil,
August 20-26, 2000.