Screening Methods for Waterlogging Tolerance at Maize (Zea mays L.) Seedling Stage
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Agricultural Sciences in China 2010,9(3):362—369 Available online at www.sciencedirect.com ; ScienceDirect
March 201O
Screening Methods for Waterlogging Tolerance at Maize(Zea mays L.)
Seedling Stage
LIU Yong—zhong,TANG Bin,ZHENG Yong—lian,MA Ke-jun,XU Shang—zhong and QIU Fa—zhan
National Key Laboratory of Crop Genetic Improvement/Huazhong Agricultural University,Wuhan 430070,P.R.China
Abstract
Waterlogging strongly affects agronomic performance of maize(Zea mays L.).In order to investigate the suitable selection
criteria of waterflooding tolerant genotypes,and identify the most susceptible stage and the best continuous treatment
time to waterlogging,20 common maize inbred lines were subjected to successive artificial waterflooding at seedling stage,and waterlogging tolerance coefficient(WTC)was used to screen waterflooding tolerant genotypes.In addition,
peroxidase(POD)activities and mal0ndia1dehyde(MDA)contents were measured for 6 of 20 lines.The results showed
that the second leaf stage(V2)was the most susceptible stage,and 6 d after waterflooding was the best continuous
treatment time.Dry weight(DW)of both shoots and roots of all lines were significantly reduced at 6 d time—point of
waterlogging,compared to contro1.POD activities and MDA contents were negatively and significantly correlated,and
the correlation coefficient was一0.9686(P<0.0001).According to the results,WTC of shoot DW can be used for practical
screening as a suitable index,which is significantly different from control and waterlogged plants happened 6 d earlier.
Furthermore,leaf chlorosis,MDA content and POD activities could also be used as reference index for material screening.
The implications of the results for waterlogging・-tolerant material screening and waterlogging-—tolerant breeding have been
djscussed in maize.
Key words:maize(Zea mays L.),waterlogging tolerance,screening method,selection criteria
INTRODUCTION
In tropical and subtropical regions,severe crop losses
are always caused by prolonged seasonal rainfal1.Ex—
cess water will result in anoxic soil witl1in a few hours
(Gambrell and Patrick 1978).The low ability of crops
to withstand low oxygen conditions in the root zone
will result in substantial yield losses(Dennis et a1.2000).
Owing to low oxygen concentrations induced by
waterlogging,the balance of active oxygen was dis—
rupted and then active oxygen species(ROS)would be
accumulated,sequentially,the membrane lipid
peroxidation and the variations of antioxidation system
were induced in cells which suffer from low oxygen stress(Blokhina 2000).POD(peroxidase),a protec—
tive enzyme involving in membrane lipid peroxidation, can eliminate active oxygen species(such as H,O,and
.OH1.Previous studies indicated that highly POD ac—
tivity was the physiological basis of plant against abi—
otic sffess(Ljn al。1984,1998;Zhou eta1.1999;Yan
f a1.1999).Furthermore,MDA(malondialdehvde),a
primary product of membrane lipid peroxidation,could
cause cell membrane functional disorder and destroy a
lot of functionally biological molecules(Mccord and
Ffidovich 1969;Dhindsa 1991;Pallitt and Young 1992).
It is known that the activities of POD were signifi—
cantly negatively correlated with MDA content。refer—
ring that P0D may play an important role in preventing
plants from cell membrane lipid peroxdation(Wang
Received 9 June,2009 Accepted 16 September,2009 LIU Yong—zhong,MSc,Associate Professor,E—mail:yongzhongliu@gmail com;Correspondence Q1U Fa—zhan,Ph D,Associate Professor,E—mail:qiufazhan@gmail com
@2010,CAAS All rights reserved Publishedby ElsevierLtd doi:10 1016/Sl671-2927(09)60105一
X Screening Methods for Waterlogging Tolerance at Maize(Zea mays L.)Seedling Stage 363
f a1.2005).
Excessive soil moisture is one of the major limiting factors for maize productivity in tropical and subtropi・
cal regions.In Southeast Asia,15%of total maize grow—
ing areas are greatly affected by waterlogging problems,
causing 25-30%losses of maize production every year
(Rathore et a1.1 998).Waterlogging is also a serious
environmental stress on maize grown at maize seedling
stage in southeastern China.In these areas,heavy spring
rainfall over a short period can lead to forming the wa—
terlogged soils for an extended period.Maize plants
will be severely damaged after a short period of
waterlogging,and large areas of maize will be lost even
after a quick inundation.Waterlogging is becoming
one worldwide abiotic threat in many agricultural areas
(Ghassemi et a1.1995).
For most plants,the capacity of roots to supply nu—
trients and water for plant growth and development is
inhibited in waterlogged soils(Musgrave and Ding 1998;