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Chang-chi Chu*, Kai Umeda, Tian-Ye Chen, Alvin M. Simmons, and Thomas H. Henneberry

Insect traps are vital component of many entomological programs for detection and monitoring of insect populations. We equipped yellow (YC), blue (BC) sticky card (BC) with 530 nm lime green (LED-YC) and 470 nm blue (LED-BC) light-emitting diodes, respectively that increased trap catches of several insect pests. The LED-YC traps caught 1.3, 1.4, 1.8, and 4.8 times more adult greenhouse whitefly Trialeurodes vaporariorum (Westwood), sweetpotato whitefly Bemisia tabaci (Gennadius) biotype B, cotton aphids Gossypium hirsutum (L.), and fungus gnats Bradysia coprophila (Lintner), respectively, compared with standard YC traps. The LED-YC traps did not catch more Eretmocerus spp. than the standard YC traps. Eretmocerus spp. are important B. tabaci parasitoids used in greenhouse biological control programs. For whitefly control in greenhouse the 530 nm lime green LED equipped plastic cup trap designed by Chu et al. (2003) is the better choice than LED-YC trap because it catches few Eretmocerus spp. and Encarsia spp. whitefly parasitoids released for B. tabaci nymph control. The LED-BC traps caught 2.0-2.5 times more adult western flower thrips Franklinella occidentalis (Pergande) compared with the standard BC traps.

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R.J. Bula, R.C. Morrow, T.W. Tibbitts, D.J. Barta, R.W. Ignatius, and T.S. Martin

Development of a more effective radiation source for use in plant-growing facilities would be of significant benefit for both research and commercial crop production applications. An array of light-emitting diodes (LEDs) that produce red radiation, supplemented with a photosynthetic photon flux (PPF) of 30 μmol·s-1·m-2 in the 400- to 500-nm spectral range from blue fluorescent lamps, was used effectively as a radiation source for growing plants. Growth of lettuce (Lactuca sativa L. `Grand Rapids') plants maintained under the LED irradiation system at a total PPF of 325 μmol·s-1·m-2 for 21 days was equivalent to that reported in the literature for plants grown for the same time under cool-white fluorescent and incandescent radiation sources. Characteristics of the plants, such as leaf shape, color, and texture, were not different from those found with plants grown under cool-white fluorescent lamps. Estimations of the electrical energy conversion efficiency of a LED system for plant irradiation suggest that it may be as much as twice that published for fluorescent systems.

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How-Chiun Wu and Chun-Chih Lin

, respectively. The PPF for all the light treatments was adjusted to 50 μmol·m −2 ·s −1 . The PPF was measured (LI-1800; LI-COR Inc.) at explant height. Fig. 1. Spectral distributions of light-emitting diodes (LEDs) and fluorescent lamp (FL). Analysis of

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Liu XiaoYing, Guo ShiRong, Xu ZhiGang, Jiao XueLei, and Takafumi Tezuka

combination of R and B and R, B, and G. PFD = photon flux density; LEDs = light-emitting diodes. Table 1. Peak wavelength and total power of light treatments. Measurements of photosynthesis. All measurements were carried out using the young and fully expanded

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Wesley C. Randall and Roberto G. Lopez

intensity LEDs. Light-emitting diodes are solid-state, single junction semiconductors that are capable of producing light wavelengths as short as 250 nm and up to greater than 1000 nm. Thus, they are useful for testing specific wavelength combinations for

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Zhong-Hua Bian, Rui-Feng Cheng, Qi-Chang Yang, Jun Wang, and Chungui Lu

sources and the plant canopies. Table 1. The spectra data and photoperiod or light duration of white (W) light-emitting diode (LED) light control (W-CK), red (R) and blue (B) LED light control [RB-CK (R:B = 4:1)], continuous light (CL) by W LED (W-CL), CL

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Michael P. Dzakovich, Celina Gómez, Mario G. Ferruzzi, and Cary A. Mitchell

-wire tomato canopy for Expt. 1 ( A ) and Expt. 2 ( B ). Treatments included overhead high-pressure sodium (OH-HPS) lamps; intracanopy light-emitting diodes (ICL-LED); hybrid supplemental lighting (OH-HPS + ICL-LED); or unsupplemented controls. For Expt. 2

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Zhengnan Yan, Dongxian He, Genhua Niu, Qing Zhou, and Yinghua Qu

red photon flux ratios Environ. Exp. Bot. 156 170 182 Albright, L.D. Both, A.J. Chiu, A.J. 2000 Controlling greenhouse light to a consistent daily integral Trans. ASAE 43 2 1737 1744 Bourget, C.M. 2008 An introduction to light-emitting diodes

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Ki-Ho Son and Myung-Min Oh

various combinations of blue and red light-emitting diodes (LEDs) used in this study. ( A ) blue:red = 0:100, ( B ) blue:red = 13:87, ( C ) blue:red = 26:74, ( D ) blue:red = 35:65, ( E ) blue:red = 47:53, ( F ) blue:red = 59:41, and ( G ) control

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Janni Bjerregaard Lund, Theo J. Blom, and Jesper Mazanti Aaslyng

developmental characteristics of potted chrysanthemums and whether elongation depends on R:FR alone or on the level of irradiance of R and FR as well. For this purpose, it was decided to create artificial twilight using light-emitting diodes (LEDs) in growth