Journal of Stress Physiology & Biochemistry, Vol. 7, No. 2,
2011, pp. 20- 33. ISSN 1997-0838
Original Text Copyright (cc) 2011 by Mittal, Kumari and Sharma
ORIGINAL
ARTICLE
Data source : Google Scholar
QueryDate : 2016-12-24
Cites : 1
Differential responses of seven contrasting species to high
light using pigment and chlorophyll a fluorescence
Mittal S., Kumari* N. and Sharma V.
Department of Bioscience and
Biotechnology, Banasthali University, Rajasthan-304022, India
*E-mail: nilima_km@yahoo.com
Fax: 91-1438-228365
Received March 11, 2011
Abstract – High light intensity may induce severe photodamage to
chloroplast and consequently cause decreases in the yield capacity of
plants and destruction of pigments, causing an overall yellowing of the
foliage. Thus, study related to light adaptation becomes necessary to
understand adaptation processes in higher plants on the basis of which
they are characterized as full sunlight or shade plants. Chlorophyll
can be regarded as an intrinsic fluorescent probe of the photosynthetic
system. The ecophysiological parameter related to plant performance and
fitness i.e. in-situ chlorophyll fluorescence measurements were
determined for different plant species in the medicinal plant garden of
Banasthali University, Rajasthan. Miniaturized Pulse Amplitude
Modulated Photosynthetic Yield Analyzers are primarily designed for
measuring effective quantum yield (ΔF/Fm’) of photosystem II under
momentary ambient light in the field. Photosynthetic yield measurements
and light-response curves suggested a gradation of sun-adapted to
shade-adapted behaviour of these plants in following order Withania somnifera> Catharanthus roseus> Datura stamonium> Vasica minora> Vasica adulta> Rauwolfia serpentina. As indicated
by light response curves and pigment analysis, Daturastramonium, Withania somnifera and Catharanthus roseus competed well
photosynthetically and are favoured while Rauwolfia serpentina, Vasica minora, Vasica adulta and Plumbago zeylanica
were observed to be less competent photosynthetically. These light
response curves and resultant cardinal points study gave insight into
the ecophysiological characterization of the photosynthetic capacity of
the plant and provides highly interesting parameters like electron
transport rate, photo-inhibition, photosynthetically active photon flux
density and yield on the basis of which light adaptability was screened
for seven medicinally important plants.
Key words:
Chlorophyll a fluorescence, Pigment,
Light, Photosystem II.
