Browsing by Author "Tang, Li-Cheng"

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Demography and Consumption of Spodoptera Litura (Lepidoptera: Noctuidae) Reared on Cabbage and Taro
(Oxford Univ Press inc, 2016) Tuan, Shu-Jen; Yeh, Chih-Chun; Atlihan, Remzi; Chi, Hsin; Tang, Li-Cheng
Spodoptera litura (F.) causes considerable economic damage to multiple agro-crops annually in many countries. In this study, the demography ofS. litura reared on cabbage and taro was investigated using the age-stage, two-sex life table at 25 +/- 1A degrees C, 60 A +/- 10% relative humidity, and a photoperiod of 12: 12 (L:D) h. Our results showed that the net reproductive rate, intrinsic rate, and finite rate of population increase on cabbage (1893.1 offspring, 0.2374 d(-1), and 1.2679 d(-1)) were all not significantly different from those on taro (1361.0 offspring, 0.2298 d(-1), and 1.2584 d(-1)). The net consumption rate on cabbage (439.1 cm(2)) was, however, three times higher than that on taro (141.7 cm(2)). According to the population parameters, both cabbage and taro are suitable host plants forS. litura. When both the population growth rate and the consumption rate were taken into consideration, the finite consumption rate on cabbage (omega = 3.8054) was significantly higher than that on taro (omega = 1.3184). In Taiwan, taro and cabbage are commonly planted in adjacent farm plots, with taro being grown from March to November and cabbage from October to April. Because of the overlapping growth periods of the two crops,S. litura can easily propagate throughout the year by switching between the adjacent crops during the overlap periods. Pest management strategies for controllingS. litura must be thoroughly reevaluated based on ecological characteristics, including its life table and consumption rate on its major host plants.
Integrating Demography, Predation Rate, and Computer Simulation for Evaluation of Orius Strigicollis as Biological Control Agent Against Frankliniella Intonsa
(E Schweizerbartsche verlagsbuchhandlung, 2021) Ding, Han-Yan; Lin, Ya-Ying; Tuan, Shu-Jen; Tang, Li-Cheng; Chi, Hsin; Atlihan, Remzi; Guncan, Ali
Erankliniella intonsa (Trybom) (Thysanoptera: Thripidae) is an important pest of numerous horticultural and agricultural crops in Taiwan. Orius strigicollis (Poppius) (Hemiptera: Anthocoridae) is a predator with high predation capacity against many pests of legumes and flowers. We used the age-stage, two-sex life table method to integrate the life table data with the predation rate of O. strigicollis fed on F. intonsa. The preadult duration, adult longevity, net reproductive rate, intrinsic rate of increase, and finite rate of increase for O. strigicollis were 13.6 d, 12.5 d, 18.8 offspring/individual, 0.1437 d(-1), and 1.1546 d(-1), respectively. The total predation of O. strigicollis during their preadult and adult stages was 60.4 and 107.3 thrips, respectively. The net predation rate was 101 prey/individual. To demonstrate the effect of releasing predators of different stages on the population growth and predation capacity, we used population projection to evaluate the predation potential of O. strigicollis, and the uncertainty of predation potential was determined by using the life tables from the 0.025th, and 0.975th, bootstrap percentiles of the finite rate of increase. Releasing third instars or adults of O. strigicollis can effectively control the pest sooner than releasing O. strigicollis eggs. In biological control, both predator and prey populations are age-stage-structured and (in most instances) individuals of both sexes are present. It is imperative that the age-stage, two-sex life table be used to precisely incorporate the variability that occurs in the developmental rate, stage differentiation, survival rates, and predation rates among individuals and between sexes. Our results demonstrate that integrating life table and predation rate data generated by using the age-stage, two-sex life table is an important technique for improving biological control programs by refining the timing and estimating the release of natural enemies. Moreover, by using the multinomial theorem, we demonstrated that a large resampling (B =100,000) is necessary to obtain more precise estimates of population parameters in applications of the bootstrap technique.