6 research outputs found
The Granulate Cutworm (Lepidoptera: Noctuidae): Biological Parameters Under Controlled Conditions, Host Plants, and Distribution in the Americas.
Feltia subterranea (Fabricius), commonly known as the granulate cutworm, is a common species of owlet moths (Noctuidae) of major agricultural importance, widely distributed in Nearctic and Neotropical regions. This study was conducted to determine the species biological parameters, gather information about its larval host plants, and assess the agricultural significance of this species in the Americas. The viability of the egg, larval, pupal stages, and prepupal period was 98, 98, and 100%, respectively, under laboratory conditions. The average duration of the egg, larval, pupal stages, and prepupal period was 3, 17, 4, and 13 d, respectively. All laboratory-reared larvae developed through five instars. The growth ratio was 1.93 for females and 1.85 for males. The duration of the larval stage was significantly longer in females than in males from the fourth instar. The duration of the pupal stage was significantly shorter in females than in males. When larval and pupal stage durations were combined, there were no significant differences in total development time as a function of sex. In total, 159 botanical taxa belonging to 41 families were recorded as host species for F. subterranea. The families with the greatest number of host species were Fabaceae (22), Poaceae (19), Asteraceae (16), Brassicaceae (13), Solanaceae (12), Amaranthaceae (7), Cucurbitaceae (7), and Malvaceae (5). It is noteworthy that the large number of native weeds used by F. subterranea as host plants could represent a significant source of infestation of crops in the agricultural landscape
Morphometry study on pre and post-hatching nerve cell bodies of lumbar spinal ganglia of Gallus domesticus
A cytomorphometric study was performed in lumbar spinal ganglia neurons of Gallus domesticus on the 10th and 18th incubation days and 8th, 35th, 61st, and 120th post-hatching days. The absolute volume of nucleus and relative volume of cytoplasm were respectively estimated by the Bach² caryometric method and by point-counting volumetry, carried out in 0.5mm thick araldite sections. The relative volume, the surface-to-volume ratio and the total surface of RER, SER, mitochondria, dense bodies, Golgi complex and the relative volume of hyaloplasm inside and outside the Nissl bodies were estimated from electronmicrographs by the Weibel et al.58 method. The conclusions were: a) there was an increase of the cell volume and a decrease of the nucleo-cytoplasmic ratio, particularly between the first two ages; b) the relative volumes of RER and SER change inversely with respect to each other: the RER increases before hatching, decreasing progressively afterwards; the changes of relative volume of dense bodies are similar to those of the RER, and the mitochondria show relatively small variations concerning the same parameter; c) the relative volume of hyaloplasm inside the Nissl bodies decreases while those outside increases; d) the surface-to-volume ratio drops sharply for all organelles from the 10th to the 18th day of incubation; after hatching, a tendency to increase is observed; e) the membrane surface-to-cytoplasmic volume ratio decreases for all organelles from the 10th to the 18th day of incubation; after hatching, this ratio increases slightly for mitochondria and Golgi complex, sharply for SER, dropping for dense bodies. The RER values alternate regularly