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Amendments with vermicomposts can reduce the incidence of pests. In this study, earthworms were fed different foods to produce four vermicomposts. A pot experiment was then conducted to assess different vermicomposts’ effects on soil fertility, and the secondary metabolite content and antioxidant capacity of Brassica chinensis L., and on the growth of Spodoptera litura larvae. The results showed that the characteristics of vermicomposts are mainly affected by food supplements, and that the application of vermicomposts can improve soil fertility, whereas increasing the soil and leaf sulfur content can decrease the relative growth rate of S. litura larvae. However, there were no significant differences in the total phenolic content (TPC), total flavonoid content (TFC), nor the DPPH free radical scavenging ability under the different treatments.

The yellow tea thrips, Scirtothrips dorsalis Hood (Thysanoptera: Thripidae), has recently become one of the key pests causing economic damage to the fruit production of mango ( Mangifera indica L.). In this study, we investigated the seasonal fluctuation of S. dorsalis populations using data mining techniques in which logistic regression (LR), decision tree (DT), and artificial neural networks (ANNs) were performed for cross analysis and the optimality of these three approaches. Subsequently, crucial factors that affect the population dynamics of S. dorsalis can be determined. Our results showed correctly classified instances of DT ≧ 83% by 10-fold cross-validation, which exhibited the highest degree of accuracy among the three methods followed by ANNs and LR. We anticipate that using an intelligent prediction model can increase prediction reliability to understand the occurrence and population dynamics of S. dorsalis under different environmental conditions. Therefore, our model could be useful for farmers to implement control measures against S. dorsalis and to manage its damages to plants. Furthermore, the model proposed can be used as a basis for assessing pesticide applications and for reducing excessive pesticide costs.

A pigmentless polyester−melamine coating catalyzed with p-toluenesulfonic acid (p-TSA) shows high impedance (∼1010 Ω·cm2) at low frequency (0.1 Hz). After the addition of pigment and additives, the impedance drops to ∼105 Ω·cm2. However, using an in situ phosphatizing reagent (ISPR) for the dual purpose of catalyzing the polyester−melamine cross-linking reaction and phosphatizing the metal surface does not show this detrimental lowering of the impedance at low frequency. Results of electrochemical impedance spectroscopy measurements and the corresponding electrical equivalent circuits show that the in situ phosphatizing coating (ISPC) applied to both bare and pretreated steel panels provides superior corrosion protection. At low frequency, the panels coated with the ISPC show 1000 times the resistance of the bare and pretreated steel panels coated with the p-TSA-catalyzed polyester−melamine paint. The simultaneous chemical process of the ISPR catalyzing desirable cross-linking reactions and forming the su...

We studied the distribution of Forcipomyia taiwana (Shiraki) in Taiwan, and found this species almost island-wide. Midge seasonality was studied for 4 yr at 3 sites in Nantou, central Taiwan, to identify the extent and causes of midge population outbreaks. The midge population in 1995 was significantly lower than in 3 other years because several typhoons inundated breeding sites. Maximum populations of F. taiwana occurred in June, July, and August. There was a highly significant correlation between the monthly abundance of F. taiwana and temperature and rainfall. A step-up multiple regression indicated that temperature was the most important factor leading to the outbreaks of F. taiwana. Temperature increases from 15°C to near 30°C will increase the midge abundance.

The formulation of in-situ phosphatizing coatings (ISPCs) was successfully performed for lacquer systems using a commercial nitrocellulose lacquer and an optimum amount of in-situ phosphatizing reagents (ISPRs). The in-situ phosphatizing lacquer (ISPL) system is stable, and shows no change in surface appearance and drying speed as compared to the unmodified lacquer (UML). The ISPLs are applied on pine, poplar, and red oak wood boards, and on cold-rolled steel, aluminum, and laminated brass panels. Immersion tests in a 3% NaCl solution showed a remarkable enhancement in paint disbonding resistance for the paint film of ISPL on wood and metals compared to that of the UML sample. The paint film protective performance of ISPLs is further evidenced by the lattice pattern tape testings, and by the cathodic delamination and electrochemical impedance spectroscopy.

An improvement in colonizing the biting midge Forcipomyia taiwana (Shiraki) was achieved by a new technique that facilitated the rearing of the midges and induced them to mate in the laboratory. At temperature of 15, 20, 25, and 30 degrees C, the development duration of the egg, 4 larval instars, and pupa decreased as temperature increased. Among 7 different diets, the blue green algae, Anabaena sp.Ch3, was the best food for rearing the midges. When the larvae were fed on the blue green algae at 25 degrees C, they needed 12 d to pupate, the pupation rate was 71.4%, the emergence rate was 80.2%, and the average longevity of the male and the female 38.3 and 22.6 d, respectively. When 120 paris were kept in a plastic cage (60 by 60 by 60 cm), swarming and copulation occurred during 0700-0900 and 1700-1800 hours. Swarm occurred throughout the cage and consisted of 10 males. The copulation was performed on the wall and the bottom of the cage, and the average duration was 290 s.