The effect of the type of diet consumed on the reproduction of Podisus nigrispinus (Dallas) was studied. Females of P. nigrispinus fed on an artificial diet had a longer preoviposition period than those fed on 3rd or 5th instar cotton leafworm larvae [Alabama argillacea (Hübner)] or mealworm (Tenebrio molitor L.) larvae. P. nigrispinus females fed on 3rd or 5th instar cotton leafworm larvae or mealworm larvae had a longer oviposition period than females on an artificial diet. The numbers of egg masses per female and of egg masses per female per day were higher when P. nigrispinus was fed on 3rd or 5th instar cotton leafworm larvae than when fed on an artificial diet. Podisus nigrispinus females fed on 5th instar cotton leafworm larvae produced a greater number of eggs per female, eggs per egg mass, and eggs per female per day, had a higher nymphal hatch rate than those fed other diets and had higher numbers of oocytes per central ovariole or per ovary than those fed on 3rd instar cotton leafworm larvae, artificial diet, house fly (Musca domestica L.) larvae or mealworm larvae.
Meloidogyne enterolobii, reported in different regions of Brazil, is a polyphagous nematode parasitising plants resistant to other root-knot nematode species. This study evaluated the resistance of six cultivars of Avena sativa, seven cultivars of Triticumaestivum and 13 hybrids of Sorghum bicolor to M. enterolobii. The experiment was conducted in a glasshouse. The soil was autoclaved and infested with 5000 eggs of M. enterolobii. The tomato ‘Rutgers’ was used as the susceptible standard to this nematode. The indices of galls, egg masses, and reproduction factor of M. enterolobii were evaluated 60 days after inoculation. This nematode did not reproduce in any of the genotypes considered resistant. The oat, wheat and sorghum cultivars studied may be recommended for crop rotation in areas infested with M. enterolobii.
In order to determine the existence of differentiation in the lengths of the testis follicles between three species and one subspecies of Triatoma a detailed morphometric analysis was carried out. Captures were performed at different sites where the species were described: Caicó, state of Rio Grande do Norte (T. brasiliensis), Petrolina, state of Pernambuco (T. brasiliensis macromelasoma), Juazeiro, state of Bahia (T. juazeirensis) and Espinosa, state of Minas Gerais (T. melanica). The records of the lengths of the testis follicles were submitted to statistic analysis. Results showed that all Triatoma studied have seven follicles in the testis, following the Triatominae pattern, which present different lengths. The morphometric data indicate the separation of the species in three groups: T. brasiliensis, T. melanica, and T. juazeirensis+T. brasiliensis macromelasoma. The obtained results are in agreement with other previous morphologic, ecologic, genetic, molecular, and phylogeographic studies, corroborating the importance of the morphometry on the testis follicles for taxonomic studies of triatomines.
The exocrine metapleural gland is unique for ants and is characterized by antibiotic production. This work aimed at comparing (1) the volume of the metapleural gland, (2) the nucleus-cytoplasm relation of the secretory cells and (3) the surface area of the bulla which corresponds to the external part of the gland in workers of Atta sexdens rubropilosa Forel, 1908. The measurements were conducted in medium-sized workers of the following groups: waste processors (workers that manipulated waste), waste removers (workers that transported the waste fragment), foragers and workers inside the fungus garden. We show that the volume of the metapleural gland reservoir is larger in groups that are more exposed to infections.
The male reproductive tract in Triatominae has a pair of testes, two vasa deferentia, a pair of seminal vesicles, four pairs of accessory glands, and an ejaculatory duct, which opens in the aedeagus. In species of the genus Triatoma each testis is formed by seven testicular follicles. Because Triatoma rubrofasciata has a common ancestor with species of Triatoma occurring in North America and because the length of testis follicles varies among different species of Triatoma a morphometrical analysis of the follicles was conducted. Triatoma rubrofasciata has seven testis follicles of variable length that are similar between left and right testes. The statistics allowed the classification in a long follicle, two medium follicles, two that are short, and two that are very short. This finding is compared with data available for other Triatominae and it is emphasized that the length of follicles testis should be included in future phylogenetic analysis of Triatominae.