Influence of sub-lethal crude oil concentration on growth, water relations and photosynthetic capacity of maize (Zea mays L.) plants.
Maize tolerance potential to oil pollution was assessed by growing Zea mays in soil contaminated with varying levels of crude oil (0, 2.5 and 5.0 % v/w basis). Crude oil contamination reduced soil microflora which may be beneficial to plant growth. It was observed that oil pollution caused a remarkable decrease in biomass, leaf water potential, turgor potential, photosynthetic pigments, quantum yield of photosystem II (PSII) (Fv/Fm), net CO2 assimilation rate, leaf nitrogen and total free amino acids. Gas exchange characteristics suggested that reduction in photosynthetic rate was mainly due to metabolic limitations. Fast chlorophyll a kinetic analysis suggested that crude oil damaged PSII donor and acceptor sides and downregulated electron transport as well as PSI end electron acceptors thereby resulting in lower PSII efficiency in converting harvested light energy into biochemical energy. However, maize plants tried to acclimate to moderate level of oil pollution by increasing root diameter and root length relative to its shoot biomass, to uptake more water and mineral nutrients.
Institute of Pure and Applied Biology, Bahauddin Zakariya University, Multan, 60800, Pakistan. habibathar@yahoo.com.|Department of Plant Sciences, Faculty of Life Sciences, The University of Manchester, Manchester, UK. habibathar@yahoo.com.
Habib-Ur-Rehman
HU
Athar
Institute of Pure and Applied Biology, Bahauddin Zakariya University, Multan, 60800, Pakistan.|Institute of Molecular Biology and Biotechnology, Bahauddin Zakariya University, Multan, Pakistan.
Sarah
S
Ambreen
Institute of Pure and Applied Biology, Bahauddin Zakariya University, Multan, 60800, Pakistan.
Muhammad
M
Javed
Institute of Pure and Applied Biology, Bahauddin Zakariya University, Multan, 60800, Pakistan.
Mehwish
M
Hina
Institute of Molecular Biology and Biotechnology, Bahauddin Zakariya University, Multan, Pakistan.
Sumaira
S
Rasul
Institute of Pure and Applied Biology, Bahauddin Zakariya University, Multan, 60800, Pakistan.
Zafar Ullah
ZU
Zafar
Institute of Molecular Biology and Biotechnology, Bahauddin Zakariya University, Multan, Pakistan.
Hamid
H
Manzoor
Department of Plant Sciences, Faculty of Life Sciences, The University of Manchester, Manchester, UK.
Chukwuma C
CC
Ogbaga
National Institute for Biotechnology and Genetic Engineering (NIBGE), Faisalabad, Pakistan.
Muhammad
M
Afzal
Department of Botany and Microbiology, King Saud University, Riyadh, Saudi Arabia.
Fahad
F
Al-Qurainy
Department of Botany and Microbiology, King Saud University, Riyadh, Saudi Arabia.|Pakistan Science Foundation, Islamabad, Pakistan.
Muhammad
M
Ashraf
D002734:Chlorophyll / Q000378:metabolism; D000077194:Chlorophyll A; D004579:Electron Transport; D007700:Kinetics; D008027:Light; D010578:Petroleum / Q000378:metabolism*; D059392:Petroleum Pollution / Q000032:analysis; D010788:Photosynthesis; D045332:Photosystem II Protein Complex / Q000378:metabolism; D018515:Plant Leaves / Q000378:metabolism; D018517:Plant Roots / Q000378:metabolism; D014867:Water / Q000378:metabolism; D003313:Zea mays / Q000254:growth & development / Q000378:metabolism*
D010578:Petroleum; D045332:Photosystem II Protein Complex; D014867:Water; D002734:Chlorophyll; D000077194:Chlorophyll A
JIP test, nitrogen; Oil pollution; PIABS, photosynthetic rate, water potential