ABSTRACT
The distribution of Aedes taeniorhynchus eggshells in Florida mangrove basin forests was determined and used to design a sampling plan. Eggshells were found in 10/11 sites (91%), with a mean +/- SE density of 1.45 +/- 0.75/cc; density did not change significantly year to year. Highest densities were located on the sloping banks of hummocks, ponds and potholes. Eggshells were less clumped in distribution than eggs and larvae and thus required a smaller sample size for a given precision level. While eggshells were flushed from compact soil that was subject to runoff during heavy rain, mangrove peat, the dominant soil of eggshell-bearing sites, was less dense and had little runoff or eggshell flushing. We suggest that eggshell surveys could be used to identify Ae. taeniorhynchus oviposition sites and oviposition patterns.
Subject(s)
Aedes/physiology , Oviposition , Animals , Female , Florida , Fresh Water , Larva , OvumABSTRACT
To test if eggshell density could be used as an index of aedine mosquito production, we compared eggshell density with the larval production of Aedes taeniorhynchus in Florida mangrove basin forests. Quantitative (n = 7) and categorical (n = 34) estimates of annual larval production were regressed against the number of eggshells per cc of soil. Significant regressions were obtained in both instances. Larval production was concentrated in zones with the highest eggshell density. We suggest that eggshell density and distribution can be used to identify oviposition sites and the sequence of larval appearance.
Subject(s)
Aedes/physiology , Oviposition , Animals , Female , Florida , Larva , Ovum , Regression Analysis , Species SpecificitySubject(s)
Bacillus thuringiensis , Culex , Mosquito Control , Pest Control, Biological , Animals , Culex/microbiologyABSTRACT
We have investigated the stimulation of cuticle production by imaginal discs ofPlodia interpunctella in tissue culture. We turned to biochemical methods to assess the quantitative effects of beta-ecdysone on chitin biosynthesis in wing discs incubated with 0.5 µC of C14-glucosamine for the final 24 h of culture.We demonstrated that imaginal discs ofP. interpunctella respond to increasing concentrations of ß-ecdysone with increased synthesis. The threshold is between 0.01 and 0.1 µg/ml of hormone (2×10-8 M to 2×10-7 M). These data represent the first demonstration of quantitative biosynthesis of chitin by a developing tissue in vitro in relation to varying amounts of hormone. Additionally, protein synthesis during the ß-ecdysone-dependent period was necessary for chitin synthesis. This system thus lends itself to a detailed investigation of the control of chitin biosynthesis.
