BACKGROUND Aedes aegypti Linnaeus is a peridomestic mosquito that lays desiccation-resistant eggs in water-filled human-made containers. Previous investigations connected egg hatching with declining dissolved oxygen (DO) that is associated with bacterial growth. However, past studies failed to uncouple DO from other potential stimulatory factors and they contained little quantitative informatio...

BACKGROUND Experiments under controlled laboratory conditions can produce decisive evidence for testing biological hypotheses, provided they are representative of the more complex natural conditions. However, whether this requirement is fulfilled is seldom tested explicitly. Here we provide a lab/field comparison to investigate the identity of an egg-marking signal of ant queens. Our study was ...

SUMMARY Indoor transmission of Ascaris suum partly depends on the physico-chemical conditions in bedding material. Temperature, pH, aqueous ammonia, moisture, occurrence and development of A. suum eggs were therefore compared in different areas (resting, intermediate and latrine) of two deep litter pens on an organic farm in four seasons. There was some variation, but mean ammonia levels were g...

For free-spawning marine invertebrates, the egg is the unit of maternal investment in offspring. For many taxa, there is a major life-history trade-off between production of many small, nutrient-poor eggs in high-fecundity species and fewer large, nutrient-rich eggs in low-fecundity species. In echinoderms, the switch from small eggs in species with ancestral-type feeding larvae to large eggs a...

We performed two experiments to determine (1) whether the metabolism and growth of embryonic snapping turtles (Chelydra serpentina) incubating in wet and dry environments are correlated inversely with the concentration of urea inside their eggs, and (2) whether urea accumulating inside eggs might be the cause of reductions in metabolism and growth by embryos. Eggs in the first experiment were i...

Shiny cowbirds, Molothrus bonariensisparasitized a high frequency (average 48%) of nests in five colonies of chestnut-capped blackbirds, Agelaius ruficapillusin Argentina. Two distinct egg morphs occurred, spotted and immaculate white eggs, as well as a few very lightly spotted intermediate eggs. The clear differences between morphs, combined with considerable variation in spotting pattern betw...

Nezara viridula L. and Euschistus servus (Say) are the predominant species of phytophagous stink bugs on corn, Zea mays L., in Georgia. Oebalus pugnax pugnax (F.) occurs in relatively low numbers, and the predatory stink bug Podisus maculiventris (Say) is commonly found. Limited information is available on natural biological control of these four stink bug species in Georgia corn fields; there...

The effect of gamma radiation on the shelf life extension of Bananas was studied. Bananas were treated with three gamma radiation doses of 0.30k Gy; 0.40k Gy and 0.50k Gy for 5 mins respectively and stored in a dry place under room conditions (25±2°C/ 80± 5% RH). The physical conditions of the radiation treated and control bananas were observed at every 2 days interval for their organoleptic pr...

Cereal-legume intercropping is important in many low-input agricultural systems. Interactions between combinations of different plant species vary widely. Field experiments were conducted to determine yield formation regularities and competition effects oat (Avena sativa L.)–black medick (Medicago lupulina L.), oat–white clover (Trifolium repens oat–Egyptian (T. alexandrinum L.) under organic f...