Determination of the physiological state of potted plants and cut flowers by modulated chlorophyll fluorescence.
Kooten, O. van; Mensink, M.; Otma, E.; Doorn, W. van;
Acta Horticulturae Year: 1991 Issue: No. 298 Pages: 83-91 Ref: 11 ref.
1991
บทคัดย่อ
Ficus benjamina (cv. Exotica), Dieffenbachia picta [D. maculata] (cv. Camilla) and Codiaeum variegatum (cv. Excellent) potted plants were kept in a shaded area (20-50 micro mol ppfd m-2 s-1 and 22 deg C) for 2-4 h, after which chlorophyll fluorescence measurements were made on 6 marked leaves/plant. The plants were then transported to auction (35 min at a minimum temperature of 17 deg ) and placed in a simulated internal environment (20 deg , 60% RH, and 15 micro mol ppfd m-2 s-1 for 12 h/day). Marked leaves were measured after 24 h. Plants were then placed at 6 micro mol ppfd m-2 s-1 and 15 deg for 78 h, after which they were transported in darkness for 24 h. The plants were subsequently stored in a simulated indoor environment and the marked leaves measured after 1 day and 3 weeks. Cut flowering stems of Rosa hybrida (cv. Sonia) were recut and placed in deionized water for 24 h in a simulated indoor environment (20 deg , 60% and 15 micro mol ppfd m-2 s-1 for 24 h/day). Chlorophyll fluorescence measurements were made at the start and end of this 24-h period. A drought period of 0, 12, 24 or 36 h followed, after which fluorescence measurements were taken and the roses placed in deionized water to recover. Fluorescence was measured again after 24 h, and 6.5 d after the start of the experiment. Transport resulted in a marked decrease in linear electron transport efficiency in D. picta and C. variegatum. However, after 3 weeks in the simulated indoor environment, linear electron transport efficiency recovered significantly in D. picta and slightly in C. variegatum. Transport had less effect on F. benjamina but this species was unable to recover when placed in the simulated indoor environment where linear electron transport efficiency decreased further. Linear electron transport efficiency in cut roses decreased markedly after a 24- or 36-h drought period, but recovered slowly when the roses were placed in water. It is concluded that measurement of the electron transport efficiency by modulated chlorophyll fluorescence is a fast and non-invasive technique to determine the physiological status of plant tissue.