Hyblaea

Abstract: . Allatectomy did not affect either food ingestion or midgut protease and invertase activity in adult female Dysdercus cingulatus Fabr., but ingestion of methoprene (juvenile hormone analogue) stimulated food consumption in the late instar caterpillars of Hyblaea puera Cramer. Implantation of brain to raise the insect's own level of brain neurosecretion also stimulated food ingestion in Hyblaea. Caterpillars which either ingested methoprene or received brain-implants showed higher levels of midgut amylase activity. However, no increase in amylase occurred after ingestion of methoprene or implantation of brain followed by starvation. A probable mechanism of hormonal influence on food ingestion and enzyme activity is discussed in the light of these results.

Abstract: This book contains all the papers on Greek Colonization published by A. J. Graham over the last forty years. In addition, it includes one new paper, not previously published, entitled 'Thasian Controversies'.

Abstract: Extensive defoliation of Avicennia germinans by Junonia evarete (Stoll) (Nymphalidae) and Hyblaea purea (Cramer) (Hyblaeidae) was noted following hurricanes Hugo (1989), Luis & Marilyn (1995) The proposed work is about evaluating the direct loss of organic matter and minerals by insect grazing during an inter-hurricane period The physiological response of the plant was assessed on perforated leaves over a 3 week period A germinans in two contrasted sites exhibited a leaf area loss close to 45% which corresponds to 50 kg DW / ha In a third site, the low consumption rate of about 083% could be related to a drop in the insect population following an earlier outbreack and full tree defoliation Damage in R mangle was exceptionally low (02%) Bulk minerals trapped in the folivore pathway was about 12 kg N and 60 g P / ha in A germinans stands Leaf grazing brings a significant accumulation of organic matter and minerals by importing compounds from other tissues of the plant This reflects a sudden change in leaf metabolism and we may hypothesise scarring reaction and/or secondary compound accumulation In any case, leaf grazing demands additional energy and minerals to maintain partially grazed leaves Moreover, such leaves are susceptible to greater loss in the event of repeated insect damage, due to higher concentrations From these results, it appears that physiological effects of insect grazing have to be considered not only as direct loss in living tissues but also as deep changes in internal fluxes of the carbon and minerals