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;