Russian Journal of Plant Physiology

, Volume 54, Issue 6, pp 741–748

Effect of phosphorus deficiency on the photosynthetic characteristics of rice plants

Research Papers

DOI: 10.1134/S1021443707060040

Cite this article as:
Xu, H.X., Weng, X.Y. & Yang, Y. Russ J Plant Physiol (2007) 54: 741. doi:10.1134/S1021443707060040

Abstract

The effects of phosphorus deficiency on the photosynthetic characteristics were studied in rice seedlings (Oryza sativa L.) every 8 days after treatment. P deficiency caused a significant reduction in the net photosynthesis rate (PN) in rice plants. During the first 16 days of P deficiency, the maximum efficiency of PSII photochemistry (Fv/Fm), the effective PSII quantum yield (ϕPSII), the electron transport rate (ETR) as well as photochemical quenching (qP) in the P-limited rice plants kept close to the control, but the excitation energy capture efficiency of PSII reaction centers (Fv/Fm) was significantly declined in the P-deficient rice leaves. Meanwhile, in the stressed leaves, we also found a significant increase in nonphotochemical quenching (NPQ) as well as in the activities of superoxide dismutase (SOD) and ascorbate peroxidase (APX). It was indicated that a series of photoprotective mechanisms had been initiated in rice plants in response to short-term P deficiency. Therefore, PSII functioning was not affected significantly under such stress. As P deficiency continued, the excess excitation energy was accumulated in excess of the capacity of photoprotection systems. When the rice suffered from P deficiency more than 16 days, ϕPSII, ETR, and qP were decreased more rapidly than that in the control plants, although NPQ still kept higher in the stressed plants. These results were also consistent with the data on the distribution of excitation energy. The excess energy induced the generation of reactive oxygen species, which might lead to the further damage to PSII functioning.

Oryza sativaphotosynthetic characteristicsphosphorus deficiencychlorophyll fluorescencephotoprotective mechanisms

Abbreviations and designations

APX

ascorbate peroxidase

ASA

ascorbic acid

Ci

intercellular CO2 concentration

Chl

chlorophyll

D

fraction of light absorbed in PSII antennae, which is dissipated as heat

ETR

electron transport rate

Ex

fraction of excess excitation energy neither dissipated in the PSII antennae nor utilized for photochemistry

Fv/Fm

maximum efficiency of PSII photochemistry

Fv/Fm

efficiency of excitation energy capture by photosystem II reaction centers

gs

stomatal conductance

NBT

nitro blue tetrazolium

P

fraction of light absorbed in PSII antennae, which is utilized in PSII antennae photochemistry

PN

net photosynthesis rate

PPFD

incident photosynthetic photon flux density

PSII

photosystem II

qP

photochemical quenching

RuBP

ribulose-1,5-bisphosphate

NPQ

nonphotochemical quenching

ROS

reactive oxygen species

SOD

superoxide dismutase

ϕPSII

effective PSII quantum yield

Copyright information

© Pleiades Publishing, Ltd. 2007

Authors and Affiliations

  1. 1.State Key Laboratory of Plant Physiology and Biochemistry, College of Life ScienceZhejiang UniversityHangzhouChina
  2. 2.Institute of HorticultureZhejiang Academy of Agriculture SciencesHangzhouChina