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Photosynthetica

, Volume 50, Issue 2, pp 161–170 | Cite as

Analyzing the significance of defoliation in growth, photosynthetic compensation and source-sink relations

  • N. Iqbal
  • A. Masood
  • N. A. Khan
Review

Abstract

Leaf canopy plays a determining role influencing source-sink relations as any change in source activity (photosynthesis) affects sink metabolism. Defoliation (removal of leaves) influences growth and photosynthetic capacity of plants, remobilizes carbon and nitrogen reserves and accelerates sink metabolism, leading to improved source-sink relations.

The response of plants to defoliation could be used to manipulate source-sink relations by removing lower and senescing leaves to obtain greatest photosynthetic capacity and efficient carbon and nitrogen metabolism under optimal and stressful environments. The present work enhances our current understanding on the physiological responses of plants to defoliation and elaborates how defoliation influences growth, photosynthetic capacity and source-sink relations under optimal and changing environmental conditions.

Additional key words

carbon defoliation nitrogen photosynthetic potential sink source 

Abbreviations

ABA

abscisic acid

C

carbon

CA

carbonic anhydrase

Chl

chlorophyll

DAS

days after sowing

gs

stomatal conductance

HI

harvest index

IAA

indole-3-acetic acid

LA

leaf area

LDM

leaf dry mass

LFM

leaf fresh mass

N

nitrogen

NR

nitrate reductase

P

phosphorus

PN

net photosynthetic rate

PEP

phosphoenolpyruvate

Rubisco

ribulose-1,5-bisphosphate carboxylase/oxygenase

SLA

specific leaf area

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© Springer Science+Business Media B.V. 2012

Authors and Affiliations

  1. 1.Department of BotanyAligarh Muslim UniversityAligarhIndia

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