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John L. Jifon, James P. Syvertsen and Eric Whaley

Technologies Inc. for loan of the Observer prototype and the Minolta SPAD-502 meters and to Dan Harkins of Opti-Sciences, Inc. for the loan of the CCM-200 prototype meter. The assistance of Jill Dunlop (CREC) is gratefully acknowledged.

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Pinghai Ding*, Jessica M. Cortell and Leslie H. Fuchigami

Nitrogen is one of the most important nutrition factors affecting grapevine growth performance and berry quality. Leaf pigments contents and leaf areas are the important indicators of grapevine nitrogen status and plant performance. In order to find a efficient way to nondestructively measure leaf nitrogen and pigments status, the SPAD meter, CCM-200 and CM-1000 chlorophyll meter in comparisons with FOSS NIR system were used in measuring leaf nitrogen, leaf chlorophyll, carotenoids, flavonoids and anthocyanins in 7-year-old Pinot Noir grape with different rate of N treatments. The results indicate that the reading of all these meters have a good relationship with leaf N, leaf chlorophyll and leaf area. But the accuracy among these meters was different, in which the accuracy of FOSS NIR is better than that of the SPAD meter, CCM-200 and CM-1000. There is the good relationship between leaf nitrogen contents, leaf area, leaf chlorophyll and carotenoids contents. Flavonoids and anthocyanins have the inverse relationship with leaf N contents and leaf area. FOSS NIR system can be use for nondestructive assessing nitrogen, leaf chlorophyll, carotenoids, flavonoids and anthocyanins whereas the other meters can only used for nondestructive assessing leaf nitrogen and leaf chlorophyll. These results indicate it is possible to use nondestructive spectral methods as the precision viticulture tools to manage vineyards nitrogen fertilization and grapevine performance.

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Henry D. Schreiber and Nicholas A. Wade

to an equivalent measurement of ≈0.35 mg of anthocyanin per g of fresh sepal, which is in general agreement with this study. Field-portable anthocyanin concentration. Studies have demonstrated that the portable CCM-200 Chlorophyll Content

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Mohammad Majdi, Ghasem Karimzadeh, Mohammad A. Malboobi, Reza Omidbaigi and Ghader Mirzaghaderi

Stress Meter; Biomonitor AB, Umea, Sweden) ( Oquist and Wass, 1988 ). Leaves were dark-adapted for 30 min before measurement of fluorescence induction. The actinic irradiance used with the PSM was 250 μmol·m −2 ·s −1 . A CCM-200 instrument (Opti

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Youbin Zheng, Diane Feliciano Cayanan and Mike Dixon

(7 d after the start of the treatments) and once a week thereafter using a CCM-200 (Opti-Sciences, Tyngsboro, MA). Leaf chlorophyll fluorescence of plants from seven randomly selected pots from each trough was measured on 19 Aug. 2004 (Day 72) with a

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Malik G. Al-Ajlouni, Jamal Y. Ayad and Yahia A. Othman

fluorescence was measured using a chlorophyll fluorometer (OS1-FL; Opti-Sciences, Hudson, NH) and SPAD using a chlorophyll meter (CCM-200 plus; Opti-Sciences). Measurements were taken between 1100 and 1300 hr from fully expanded and sun-exposed leaves

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Christopher Parry and Bruce Bugbee

measured in all studies with a nondestructive optical meter (model CCM-200; Opti-Sciences, Hudson, NH). This meter measures the transmission of two wavelengths of radiation through plant leaves: red at ≈650 nm and near IR at ≈900 nm. Increased chlorophyll

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Diane Feliciano Cayanan, Mike Dixon, Youbin Zheng and Jennifer Llewellyn

) of the youngest fully expanded leaf without visible injury was determined using a CCM-200 (Opti-Sciences, Tyngsboro, MA). Plant shoots were divided into stems and leaves. Leaf area (LA) was measured using a leaf area meter (LI-3100; LI-COR, Lincoln

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Jong-Goo Kang, Rhuanito Soranz Ferrarezi, Sue K. Dove, Geoffrey M. Weaver and Marc W. van Iersel

to calculate the pore water EC ( Hilhorst, 2000 ). Leaf chlorophyll concentration index (CCI) was measured on uppermost fully expanded leaves using a leaf chlorophyll meter (CCM-200; Apogee Instruments). The CCI is closely, but not linearly, related

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Wenjing Guan and Xin Zhao

recorded. Leaf area was measured with an area meter (LI-300C; LI-COR Environmental, Lincoln, NE). A leaf porometer (SC-1; Decagon Devices, Pullman, WA) and a chlorophyll content meter (CCM-200; Opti-Sciences, Hudson, NH) were used to measure stomatal