In vertebrates, it is well documented that the parental consumption of high-fat diet increases the risk of Attention-Deficit Hyperactivity Disorder (ADHD) in offspring. While insects have long been used as popular study organisms in various biological research, few studies have explored how the nutritional quality of parental diet affects offspring behavioral phenotypes associated with ADHD in insects. Here we used the bean bug, Riptortus pedestris (Hemiptera: Alydidae), as a study organism to test the effect of parental high-fat diet on offspring hyperactivity, impulsivity, and diffuse attention, which are widely held as the three core symptoms of ADHD in vertebrates. Peanut was used as the high-fat diet while soybean was the control. Parental high-fat diet consumption induced hyperactivity in R. pedestris offspring. Compared to the controls, the hyperactive offspring of parents fed on high-fat diet were behaviorally more impulsive and less attentive, as they were found to be highly attracted to visual stimuli but losing attention easily. Collectively, these results provide the experimental evidence that the parental consumption of high-fat diet results in increased hyperactivity, impulsivity, and diffuse attention in an insect. This study implies that the well-known association between parental high-fat diet and offspring ADHD is conserved across the tree of life and opens up the new horizons that insects can arise as novel and feasible models for studying the mechanism and evolution of this common neurodevelopmental disorder in humans.

Baculum elongatum has a long, thin shape that resembles a twig, propagates by parthenogenesis, changes body color, and drops eggs, all of which suggests its potential in the commercial market, especially as an educational pet insect. This study was carried out to determine the best hatching environment and an alternative or artificial diet for rearing B. elongatum to be developed as a commercial and educational pet insect. Oviposition was performed by females without fertilization by the sperm of males. The oviposition period was 42.2 ± 22.7 days and the number of eggs per female was 109.5 ± 70.5 eggs. The hatch rate was 73.3% at 25°C and 66.7% after low temperature treatment (8°C for 60 days). In nature, B. elongatum overwinters as an egg, but it can be assumed from the results that cold temperatures were not required for hatching. The hatch rate was 98.2% in the treatment using floral foam, fermented sawdust, and leaves. Clover(Trifolium repens) was an excellent diet as it was similar to the host plant and could be used as an alternative diet. The rate of reaching adulthood for the insects was 66.7% on an artificial diet containing 25% acacia leaves. For sustainable mass rearing of nymphs or adults of B. elongatum, a natural diet could be used such as acacia (Robinia pseudoacacia), white oak (Quercus aliena), chestnut (Castanea crenata var. dulcis), and bush clover (Lespedeza bicolor), or an alternative diet such as clover or artificial diet. To rear nymphs and adults of B. elongatum, natural diet such as acacia, white oak, chestnut, or bush clover leaves, or an alternative diet such as clover or an artificial diet can be used.

Riptortus pedestris (Fabricius) (Hemiptera: Alydidae) recently become an important fruit-spotting bug of apple and sweet persimmon trees in Korea. Although fruits of cultivated species are generally known to be unsuitable food for the fruit-spotting bugs, dietary importance of fruits of apple and sweet persimmon for R. pedestris is unknown. We evaluated fruits of apple and sweet persimmon with or without soybean seeds as a food source for R. pedestris by investigating nymphal development time, nymphal mortality, preovipositional period, fecundity, and adult size in the laboratory. None of 1st instar R. pedestris fed only on a fruit of apple or sweet persimmon became second instar nymph. When provided with soybean seeds together, both the fruits did support the nymphal development and the reproduction of R. pedestris. However, diets including soybean and one of the fruits were not better than control diets consisting of soybean seeds with or without vitamin C. Therefore, apple and sweet persimmon are not essential food sources for the development and the reproduction of R. pedestris. These results suggest that R. pedestris may not reproduce on the fruit trees, thus explain absence of either their eggs or their nymphs on the fruit trees in the fields.

Development of pellet-type artificial diet for insect was tried by using a twin screw extruder(TSE). Screws were arranged several times and two reverse screws were equipped on the foreparts of 2 axes of TSE. Pellet-type diet could be produced successfully under conditions of TSE set as the following. , 300 rpm of main motor speed, 228 rpm of feed motor speed, 75㎖/min of running water speed and 5 ㎜ of extrusion diameter. The optimum adding quantity of water to the manufactured diet was 1.2~1.5 times of dry diet. On the rearing results of beet armyworm, Spodoptera exigua and common cutworm, Spodoptera litura with the pellet-type diet, the final survival ratio (emergence rate) of these two species was over than 50%, and so it was concluded that the manufactured pellet-type artificial diet was sufficient dietetically to rear those insects.