• Korean journal of applied entomology
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• v.62 no.4
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• pp.315-323
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• 2023

The brassica leaf beetle, Phaedon brassicae Baly (Coleoptera: Chrysomelidae), is one of the important pests infesting cruciferous vegetables. In order to understand the biological characteristics of the insect, we investigated the effects of temperature on development of each life stage, adult longevity and fecundity of P. brassicae at four constant temperatures of 15, 20, 25 and 27.5℃ for immature life stage and five constant different temperatures of 10, 15, 20, 25 and 27.5℃ for adult stage. Eggs and larvae successfully developed next life stage at temperature tested. The development period of egg, larva, and pupa decreased as temperature increased. Lower developmental threshold (LDT) and thermal constant (K) were calculated using linear regression as 8.7℃ and 344.73DD, respectively. Lower and higher threshold temperature (TL and TH) from egg to adult emergence were estimated by Briere function as 5.3℃ and 40.4℃, respectively. Adults produced eggs at the temperature range between 10℃ and 27.5℃, and showed an estimated maximum number, ca. 627.5 eggs at 21.7℃. Adult oviposition models including aging rate, age-specific survival rate, age-specific cumulative oviposition, and temperature-dependent fecundity were constructed. Temperature-dependent development models and adult oviposition models would be useful components to understand the population dynamics of P. brassicae and to establish the strategy of integrated pest management in cruciferous crops.

• Korean Journal of Agricultural Science
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• v.17 no.1
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• pp.1-8
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• 1990

The paper board sludge(PBS) itself and compost sludge manure(CSM) mixed with sawdust, fowl droppings and urea to the PBS were treated to soybean plants to find the effects of growing characters, yield components, and nutritional compounds in the plant tissues. 1. Percentages of missing plants were 5-9% and 3.6-4.1% in the treatments of PBS and CSM, respectively. After that, the plants were restored to normal conditions. Anyway it is not desirable to use the paper board sludge and immature compost sludge manure in seeding time or to young seedlings. 2. Growth of the plant height was retarded in early growing phase, but it was normal in later stages. And the width and length of the largest leaf, numbers of main stem nodes and pods were not significant among the treatments. 3. The yield intends to increase through the treatments of 1,200, 1,600, and 2,000Kg PBS per 10a. In the CSM treatments with high rate of sawdust, fowl droppings and urea, the numbers of pods and grains were higher than the treatment of high content of PBS. 100-grain and one liter weights were opposite intention. It was suggested that the excess nitrogen amounts from the compost sludge manure than conventional fertilization affected to the yield components. 4. The contents of the main chemical compounds such as N, $P_2O_5$, $K_2O$, Ca, Mg were determined. The concentrations of nitrogen were higher in the treatment of PBS and CSM than none and control. 5. In conclusion, the nutritional effects of PBS were in evidence. To use the sludges, it should be fermented with adequate additives to improve the aeration, C/N ratio, activity of microbial, and other conditions. The sludges could be used to crops as a fertilizers effectively.