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Introduction: Histological stains are biological dyes which colour tissue in order to aid optical differentiation of tissue component. Dyes are coloured substance which impact colour for material such as textile, cosmetic, food, drugs, rubber plastics, hair, fur and tissues. There are two types of dyes namely; natural dyes and synthetic dyes. Allium cepa is an imperative, evergreen plant, which belongs to the family Amaryllidaceace commonly called bulb onion. Aim: This research work aimed at evaluating the staining capability of onion extract as counter stain when haematoxylin was used as primary stain. Methods: Tissue blocks sections of liver and kidney organs were made from the Wistar rat. Serial sections labelled A to M were made from each block and stained with Harris haematoxylin. Section A was counterstained with eosin, as control. Different preparations of extracts of the onion skin were used to counter stain sections of kidney and liver tissues. Group B to Mwere kidney and liver tissues stained as follows: B, E, H and K (5% aqueous and ethanolic extract with ferric chloride, 5% aqueous and ethanolic extract with potassium aluminium alum, and 5% aqueous and ethanolic extract without mordant, for 10 and 20 minutes). C, D, F, G, I, J, L and M (5% aqueous and ethanolic extract with ferric chloride, 5% aqueous and ethanolic extract with potassium aluminium alum and 5% aqueous and ethanolic extract without mordant for 10 and 20 minutes). Results: The skin extract of Allium cepa stained the cytoplasm of cells and connective tissues in shades of reddish brown to yellowish brown. The study established the cytoplasmic counter-staining ability of the extract of Allium cepa. Conclusion: It is therefore suggested that onion skin extract solution can be substituted for eosin due to its domestic availability, ease of preparation and above all, its good cytoplasm contrast with the nuclear stain.

Pseudacteon curvatus and P. obtusus are two species of parasitic phorid flies (Diptera: Phoridae), introduced in the southern USA for biological control of Solenopsis fire ants (Hymenoptera: Formicidae). The preference of both parasitoid species (P. curvatus and P. obtusus) for native Solenopsis fire ants (S. geminata complex) versus imported fire ants, S. saevissima complex (S. invicta and S. richteri) was investigated in four-choice olfactometer assays. We hypothesized that differences in the venom alkaloid profiles of fire ant species mediate host preference in phorid flies. In olfactometer bioassays, female P. obtusus showed preference for the venom alkaloid (cis + trans alkaloid mixture) of the imported S. invicta fire ant over the venom alkaloid of the native geminata fire ant. Similarly, P. obtusus showed preference for the venom alkaloid of the S. richteri fire ant over that of the native S. geminata ants. Pseudacteon curvatus also showed preference for the venom alkaloid of the S. invicta and S. richteri fire ants over that of the native geminata ants in separate bioassays. The results suggest that host preference in P. curvatus and P. obtusus is mediated, at least in part, by differences in the venom alkaloid profile of various fire ant species. This finding may explain why Pseudacteon species associated with either the S. geminata or S. saevissima complexes have not switched to the other group despite the overlap of native and imported fire ants in some areas of their distributions.

Corn earworm, Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae), has emerged as an injurious insect pest to hemp, Cannabis sativa L., a crop newly reintroduced to the United States. Growing hemp presents a potential alternative economic opportunity for farmers but can be challenging with a market that is unstable and just developing. One of the most notable production challenges is managing corn earworm, an insect pest that is particularly damaging when it feeds on flower buds produced in cannabinoid varieties, creating extensive bud tunneling and wounds that allow entry of pathogens that can aid development and presence of bud rot. Damage to seeds is of lesser concern in hemp cultivars grown for grain and minimal risk is associated with hemp grown for fiber. Our ability to research hemp has only recently been allowed as production was largely suspended following World War II and, as such, there has been limited opportunity to develop information for empirically-based pest management recommendations. Further complicating development of integrated pest management (IPM) strategies are regulatory challenges associated with providing registration support to add hemp to pesticide labels, as it was not formally recognized as a crop by U.S. regulatory agencies until late 2019. Research needs and challenges to develop effective IPM programs for corn earworm on hemp are discussed here.

The chemical composition of Melanthera scandens (MS) methanol (MeOH) extract is yet to be fully comprehended. Chemical composition of a plant extract is closely related to the biological activity of the plant material, in phytomedicine. In this study, chemical analyses of MS extracts were carried out with the aim of identifying the organic chemical constituents.

The high surface area to volume ratio of terrestrial insects makes them highly susceptible to desiccation mainly through the cuticle. Cuticular permeability (CP) is usually the most important factor limiting water loss in terrestrial insects. Water loss rate, percentage of total body water (%TBW) content, CP, and desiccation tolerance were investigated in workers of four Solenopsis species in the southeastern USA. We hypothesized that tropical/subtropical ants (S. invicta and S. geminata) will have lower CP values and tolerate higher levels of desiccation than temperate ants (S. richteri and S. invicta &times, S. richteri). The %TBW content was similar among species. Solenopsis invicta had a 1.3-fold and 1.1-fold lower CP value than S. invicta &times, S. richteri and S. richteri, respectively. Solenopsis geminata had a 1.3-fold lower CP value than S. invicta &times, S. richteri, and a 1.2-fold lower CP value than S. richteri. The LT50 values (lethal time to kill 50% of the population) ranged from 1.5 h (small S. geminata) to 8.5 h (large S. invicta). Desiccation tolerance ranged between 36 and 50 %TBW lost at death and was not related to a species&rsquo, location of origin. This study is the first report of water relations of S. invicta &times, S. richteri. It demonstrates that desiccation stress differentially can affect the survival of different Solenopsis species and implies that environmental stress can affect the distribution of these species in the southeastern USA.

Some fire ants of the genus Solenopsis have become invasive species in the southern United States displacing native species by competition. Although the displacement pattern seems clear, the mechanisms underlying competitive advantage remain unclear. The ability of ant workers to produce relatively larger amount of alarm pheromone may correspond to relative greater fitness among sympatric fire ant species. Here we report on quantitative intra-specific (i.e. inter-caste) and inter-specific differences of alarm pheromone component, 2-ethyl-3,6-dimethylpyrazine (2E36DMP), for several fire ant species. The alarm pheromone component was extracted by soaking ants in hexane for 48 h and subsequently quantified by gas chromatography-mass spectrometry at single ion monitoring mode. Solenopsis invicta workers had more 2E36DMP than male or female alates by relative weight; individual workers, however, contained significantly less pyrazine. We thus believe that alarm pheromones may serve additional roles in alates. Workers of Solenopsis richteri, S. invicta, and hybrid (S. richteri × S. invicta) had significantly more 2E36DMP than a native fire ant species, Solenopsis geminata. The hybrid fire ant had significantly less 2E36DMP than the two parent species, S. richteri and S. invicta. It seems likely that higher alarm pheromone content may have favored invasion success of exotic fire ants over native species. We discuss the potential role of inter-specific variation in pyrazine content for the relationship between the observed shifts in the spatial distributions of the three exotic fire ant species in southern United States and the displacement of native fire ant species.

There has been a resurgence in the cultivation of industrial hemp, Cannabis sativa L., in the United States since its recent legalization. This may facilitate increased populations of arthropods associated with the plant. Hemp pests target highly marketable parts of the plant, such as flowers, stalks, and leaves, which ultimately results in a decline in the quality. Industrial hemp can be used for several purposes including production of fiber, grain, and cannabidiol. Thus, proper management of pests is essential to achieve a substantial yield of hemp in the face of climate change. In this review, we provide updates on various arthropods associated with industrial hemp in the United States and examine the potential impact of climate change on corn earworm (CEW) Helicoverpa zea Boddie, a major hemp pest. For example, temperature and photoperiod affect the development and diapause process in CEW. Additionally, drought can lead to a reduction in hemp growth. Host plant diversity of CEW may prevent populations of the pest from reaching outbreak levels. It is suggested that hemp varieties resistant to drought, high soil salinity, cold, heat, humidity, and common pests and diseases should be selected. Ongoing research on effective management of CEW in hemp is critical.

Stem bark of Alstonia boonie (1.24 kg) was exhaustively extracted with 95 % aqueous methanol. The crude extract was defatted with n-hexane and thereafter subjected to extensive chromatograp...

Sugar feeding is known to enhance lifespan in many parasitoid species. Several species of phorid flies in the genus Pseudacteon (Diptera: Phoridae) have been introduced in the Southern U.S.A. for the biological control of imported fire ants of Solenopsis species (Hymenoptera: Formicidae). Pseudacteon species are short-lived flies and little is known about their nutritional ecology. Results from previous studies in our laboratory show that one of the introduced species, Pseudacteon tricuspis Borgmeier, is capable of feeding on sugar sources with a significant increase in lifespan. However, in Pseudacteon phorid flies, the degree to which sugar feeding can enhance the lifespan of other species is not clear, nor is it known whether there is a relationship between body size and longevity. In the present study, the effect of sugar feeding on the survival of three phorid fly species of different body sizes, Pseudacteon cultellatus Borgmeier, Pseudacteon curvatus Borgmeier and Pseudacteon obtusus Borgmeier, is investigated. For all three species, flies continuously provided with 40% or 20% sucrose solution live longer than individuals provided water only or 40% sucrose solution only on the first day of adult life. However, the degree to which sugar feeding enhanced longevity varies by species and is highest for P. obtusus. The data also indicate that longevity in Pseudacteon phorid flies is related to body size: the largest species (P. obtusus) lives significantly longer than the smaller species (P. cultellatus and P. curvatus). These results suggest that adults of all three Pseudacteon species are capable of feeding on sucrose solution and that sugar feeding can enhance their longevity. The significance of these results is discussed in relation to the field performance of Pseudacteon phorid flies as biological control agents of imported fire ants.

A two-year study was conducted on an Alfisol in the humid tropics of southwest Nigeria to investigate the effects of tillage and intercropping on soil water characteristics, performance of maize (Zea mays L.) and groundnut (Arachis hypogea L.). The experiment was a split-plot design with tillage methods as the main plot and intercropping as the sub-plots in a completely randomized design with four replications. Tillage treatments were conventional tillage (CT) and no-tillage (NT) while the cropping treatments were sole maize, sole groundnut and intercropped maize + groundnut. Gravimetric soil water content (swgc) showed that NT had higher soil water content in all cropping treatments than CT. NT had significantly (p NT intercropping > CT intercropping > sole maize CT. For groundnut, the trend was NT sole groundnut > NT intercropped > CT sole groundnut > CT intercropped. Key words: Tillage, intercropping, soil water retention, infiltration.

A survey of white-throated monkey (Cercopithecus erythrogaster) in Okomu National Park, Edo State, Nigeria was conducted to estimate the population density. Line transect method of wildlife population determination was adopted. Two censuses were carried out in each of the eight transects (2.0km length, 0.02km width and at interval of 1.0km) randomly selected in a period of one month. Direct method of animal sighting was employed. Mean population density of white-throated monkeys in Okomu National Park was 14/km 2 , implying that hunting activities was low in the Park.

No Abstract.Global Journal of Agricultural Sciences Vol. 5 (2) 2006: pp. 141-146

No Abstract.Global Journal of Agricultural Sciences Vol. 5 (2) 2006: pp. 161-165

A study on lumber recovery efficiency was carried out to quantify wood wastage during lumbering process in the artisanal sector. The study was carried out in randomly selected felling areas of Agoi-Ekpo, Bateriko, Kanyanban, Onyen-Ekpon and Oban all in Cross River State between October 2003 and October 2004.Five commercial timber species selected for the study were milicia excelsa , Pterocarpus osun , Nauclea diderichii , Terminalia ivorensis and Gosswellondedron spp. The study showed that log conversion in the artisanal sector result in a high degree (57%) of wastage of total tree volume while the mean recovery ratio for the species are 0.40, 0.46, 0.47, 0.42 and 0.39 for Milicia excelsa , plerocarpus osun , Nauclea diderichii , Terminalia Ivorensis and Gosswellondendron spp respectively. It is recommended that gradual phasing out of stump site wood conversion and proper saw maintenance through training among others be initiated to improve the low wood recovery observed in stump site wood conversion. Keywords: lumber, artisinal sector, recovery efficiency Journal of Agriculture, Forestry and the Social Sciences Vol 3(1) 2005: 41-50

Summary Food habits, growth rate, reproductive performance, carcass characteristics and nutritive value of the giant snail were investigated in the field and with captive snails. Food consumed included fresh plant material, livestock faeces and dead animals. Clutch sizes varied from six to twelve and incubation periods from 30 to 45 days. Weight gains of young snails of average weight 20 g fed on diets of single plant species ranged from 18% on Talinum triangulare leaves to 200% on pawpaw fruit. Best growth was shown on leaves of cassava and cocoyam, grain chaff of maize and fruit of pawpaw. Dressing-out percentage of snails of 200 g weight was 37.8%. Nutrient composition of the edible portion compared closely with that of domestic livestock. Nitrogen-free extractive content was high at 5% and fat low at 1.3%. Mineral analysis revealed a high iron content of 12.2 mg/100 g in the edible carcass. The experiments showed that the snail could thrive in captivity on a variety of locally produced feeds, many of them rejected as waste products. It shows great promise as a domestic animal capable of being reared with negligible capital outlay.

Summary The African giant rat Cricetomys gambianus Waterhouse is found in a wide variety of habitats in Ibadan district. These include an abandoned farm in a degraded deciduous forest, a zoological garden complex, Agodi; and a forest plantation of teak (Tectona grandis L.F.), human habitation and derived Guinea savanna. They located their burrows in the most heavily shaded parts of the habitats. Burrows were found mostly inside deserted termite mounds and amongst roots of trees probably to provide insulation from heat. They are nocturnal, omnivorous rodents, feeding on a wide variety of root crops, fruits, molluscs and insects. Fruits of the oil palm (Elaeis guineensis Jacq.) or their remains were found in all burrows. Information on habitat preferences, food habits, as well as that obtained from the dimensions and design of burrows which are reported in this paper later provided a basis for the design of cages and husbandry techniques for a programme of domestication of this rodent, which is currently being carried out at University of Ibadan, Nigeria.

Summary Ground and aerial surveys were used to determine the abundance and distribution of the large herbivore community in the Borgu sector of Kainji Lake National Park, Density estimates of thirteen species, assessed during dry season road counts, indicated about five individuals per km2 in the upland savanna regions and about three times this number in the Olli river valley. Hartebeest and roan antelope comprised 60% of the upland savanna density while kob comprised 74% of the Olli river valley density. Total populations for the reserve, assessed during dry season aerial surveys, indicated that hartebeest and roan antelope were the two most abundant species, with about 2700 and 2200 individuals, respectively. The only other species with estimated populations greater than 500 were elephant and grey duiker. Total populations during the wet season, assessed during an aerial survey, indicated considerably fewer animals than during the dry season. Densities of the six most abundant species during the 1970–1976 period did not appear to have changed significantly, with the exception of elephant and roan antelope which were more abundant. Biomass density for the large herbivore populations in the upland savanna and for the Olli valley were almost the same being approximately 1200 kg/km. RESUMEE Des comptages terrestres et aeriens ont ete menes pour determiner l'abondance et la distribution de la communaute de grands herbivores dans le secteur de Borgu, au Lake Kanji National Park. Des estimations de densite pour traze especes par comptages routiers durant la saison seche donnaient environ cinque individus au km2 dans la savane d'altitude et environ trois fois plus dans la vallee de la riviere Olli. Le bubale et l'antilope roanne representent 60% de la densite en savane d'altitude alors que le cob compte pour 74% dans celle de la vallee de la riviere Olli. Des comptages aeriens de toute la population de la reserve effectue en saison seche, indiquent que le bubale et la roanne sont les deux especes les plus abondantes avec environ 2700 et 2200 individus respectivement. Les seules autres especes dont les populations sont estimees a plus de 500 individus sont l'elephant et le cephalophe gris. L'ensemble de la population, durant la saison des pluies et estime par comptage aerien, indique la presence d'un beaucoup plus petit nombre d'animaux que pendant la saison seche. Les densites de population des six especes les plus abondantes entre 1970 et 1976 ne semblent pas avoir change significativement, a l'exception de l'elephant et de l'antilope roanne qui etaient moins abondants. La biomasse des populations de grands herbivores est presque la měme dans la savane d'altitude que dans la vallee de 1'0lli: elle est d'environ 1200 kg/km2.

Meat is short in southern Nigeria. Wild animal meat is popular, but the wildlife is seriously depleted. To help supply the demand for meat and also ease the pressure on the wildlife, a quick-breeding species, the giant or pouched rat, is being domesticated. The author describes some of the widely held taboos about this meat, which nevertheless is in considerable demand.