Life history of immature Angoumois grain moths, Sitotroga cerealella (Olivier), was studied on dent corn (Pioneer 3320) at 10, 15, 20, 25, 30, 35, and 40 C and at 43, 53Ð61, 75Ð76, and 82Ð87% RH under laboratory conditions. At 10 and 40 C, none of the stages survived at any relative humidity. Temperaturewas themain factor affecting egg incubationperiod, larval-pupal development time, and egg an...

Nutritional enhancement of crops using genetic engineering can potentially affect herbivorous pests. Recently, oilseed crops have been genetically engineered to produce the long-chain omega-3 polyunsaturated fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) at levels similar to that found in fish oil; to provide a more sustainable source of these compounds than is currentl...

Eutrophication is a large problem in many marine and brackish-water areas. One of the consequences is algae-induced turbidity affecting visually feeding organisms, and behavioural changes of fish and other animals are common in turbid water. The aim of this study was to compare the performance of larval pike Esox lucius in turbid and clear water. We experimentally studied habitat choice, prey a...

The insecticidal characteristics of two Spodoptera exigua multiple nucleopolyhedrovirus (SeMNPV) strains produced on two different S. exigua colonies were measured using the same two host colonies. These strains constitute the active ingredients of the biological insecticides Vir-ex and Spexit and were produced on insect colonies from Spain and Switzerland. Demographic characteristics of insect...

We analyzed the accumulation of six phytohormones and phytohormone-related compounds in a wheat, Triticum aestivium L., genotype, 'Molly', after attacks by avirulent and virulent Hessian fly, Mayetiola destructor (Say) (Diptera: Cecidomyiidae), larvae, respectively, and we examined the expression of genes in the jasmonic acid (JA) pathway by Northern blot analysis. Compared with uninfested plan...

While adult green dock leaf beetles Gastrophysa viridula use tarsal adhesive setae to attach to and walk on smooth vertical surfaces and ceilings, larvae apply different devices for similar purposes: pretarsal adhesive pads on thoracic legs and a retractable pygopod at the 10th abdominal segment. Both are soft smooth structures and capable of wet adhesion. We studied attachment ability of diffe...

Tuta absoluta (Meyrick, 1917) is a key tomato pest in South America and, recently, in Europe and Africa. To develop efficient control methods for this pest, adequate rearing protocols are desirable. As an alternative to tomato leaves (natural diet), we evaluated four artificial diets. Biological traits including larval and pupal viability and development time, pupal weight and deformations were...

The effects of larval crowding on survival, weight at metamorphosis and development time were assessed in the dengue mosquito, Aedes aegypti L., under a controlled environment. Larval cohorts were bred at 7 different densities (4, 8, 16, 32, 64, 128 and 256 larvae / 175 ml pot), while keeping constant water volume and food amount and quality, under controlled temperature and photoperiod. Natura...

Larval performance of the cottonwood leaf beetle,Chrysomela scriptaF., was evaluated in relation to genetic variation in phytochemical characteristics among Þrst year micropropagated ramets of Þve aspen clones (Populus tremuloidesMichx.). Foliage from the juvenile ramets used in this experiment exhibited moderate variation in nitrogen, phenolic glycosides, and condensed tannin concentrations am...

Grass selections including 10 zoysiagrasses, 18 paspalums, 34 Bermuda grasses, tall fescue, creeping red fescue, and perennial ryegrasses with andwithout endophyte were evaluated for potential resistance to fall armyworm, Spodoptera frugiperda (J. E. Smith), larvae. Laboratory evaluations assessed the degree of antibiosis among 70 grass lines to Þrst-instar fall armyworms. When all parametersme...