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A series of tests were conducted to determine the susceptibility of eggs and neonates of the lesser grain borer Rhyzopertha dominica (F.) (Coleoptera: Bostrichidae = Bostrychidae), exposed to the insect growth regulator, methoprene, on filter paper and on rough rice. In the first test, the hatch rate of eggs exposed on filter paper treated with methoprene at the label rate of 0.003 mg [AI]/cm2 when used as a surface treatment in structures was 52.0 ± 7.3% compared to 93.0 ± 3.3% on untreated controls. In the second test, eggs were exposed to a dose-response series of 0.00003 to 0.03 mg[AI]/cm2. Egg hatch was directly proportional to concentration and ranged from 85.0 ± 2.0% on untreated controls to 26.7 ± 8.3% at the highest concentration tested. In the third test, 1 ppm of methoprene was sprayed on long grain rough rice (paddy) (Cocodrie variety), and then individual kernels were cracked and an egg of R. dominica was placed directly on the kernel. On untreated rice kernels, 67.5 ± 11.6% of the eggs hatched and were able to bore inside, and all of these larvae emerged as adults. In contrast, 40.0 ± 5.3% of the eggs placed on treated cracked kernels were able to develop to where the larvae were visible through X-ray detection, but none emerged as adults. In the final test, newly-emerged adults were exposed on rough rice treated with 1 ppm methoprene. The number of eggs from adults on untreated rice was 52.1 ± 4.3 eggs per female, and on treated rice the average egg production was 12.5 ± 1.1 eggs per female. Methoprene applied on a surface or on rough rice affected development of egg hatch also reduced fecundity of parent adults exposed on the treated rough rice.

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The long term storage effects on stingless bee (Tetragonula laeviceps-pagdeni) honey from SE Asia (Thailand) were examined using physicochemical parameters. Fresh stingless bee honey was stored at 4, 30, and 45˚C for 6 and 12 months. The results show that the moisture, ash, and electrical conductivity change little over time and temperature storage. The total acidity increased when stored for 6 and 12 months. pH, diastase, and HMF demonstrated statistically significant changes for both time and temperature storage. The carbohydrates (fructose, glucose, and maltose) decreased during time and temperature storage, but the changes were not statistically significant. Storage for the longest time period (12 months) and highest temperature (45˚C) resulted in the greatest changes. Storage at 4˚C for 12 months resulted in the least change and the honey was, by and large, unchanged from fresh honey.Efectos del almacenamiento a largo plazo en la miel de abejas sin aguijó n (Hymenoptera: Meliponini: Apidae)Los efectos del almacenamiento a largo plazo de la miel de la abeja sin aguijó n (Tetragonula laeviceps-pagdeni) de sureste de Asia (Tailandia) han sido examinados mediante el uso de parámetros físico-químicos. La miel de abejas sin aguijó n fresca se almacenó a 4˚C, 30˚C y 45˚C durante 6 y 12 meses. Los resultados muestran que la humedad, las cenizas y la conductividad eléctrica cambian poco con el tiempo y la temperatura de almacenamiento. La acidez total se incrementó cuando se almacena durante 6 y 12 meses. El pH, la concentració n de diastasa y el HMF demostraron cambios estadísticamente significativos en relació n con el tiempo y la temperatura de almacenamiento. Los hidratos de carbono (fructosa, glucosa y maltosa) disminuyeron durante el tiempo y la temperatura de almacenamiento, pero los cambios no fueron estadísticamente significativos. El almacenamiento durante un período mayor de tiempo (12 meses) y a temperatura más alta (45˚C) originaron los mayores cambios. El almacenamiento a 4˚C durante 12 meses originó el menor cambio y la miel varió , en general, mucho menos en relació n con la miel fresca.

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Several physical and chemical attributes of rice were evaluated to determine which character would be best to use to assess multiple rice varieties for resistance to the lesser grain borer, Rhyzopertha dominica (F.). Laboratory tests were conducted on single varieties of long-, short-, and medium grain-rice to develop procedures and methodologies that could be used for large-scale screening studies. Progeny production of R. dominica was positively correlated with the percentage of broken hulls. Although kernel hardness, amylose content, neonate preference for brown rice, and adult emergence from neonates varied among the three rice varieties tested they did not appear to be valid indicators of eventual progeny production, and may not be useful predictors of resistance or susceptibility. Soundness and integrity seem to be the best characters to use for varietal screening studies with R. dominica.