Effects Of Genotype,Environment And G×E Interaction On Main Quality Traits Of Wheat

The quality improvement is one of importance object for wheat breeding,its main contents include:shape character,nutritional quality and milling quality,they are closely interrelated each other.Improvement of end-use quality in wheat depends on a thorough understanding of current wheat quality and the influences of genotype(G),environment(E),and genotype by environment interaction(G×E)on quality traits.Same traits of common wheat cultivars and advanced lines regional trails in Huang-Huai area in three locations in 2003～2004 and 2004-2005 and nineteen common wheat cultivars and advanced lines were grown in four locations during 2005-2006 and 2006-2007cropping seasons were analysed statistically.The result showed as follows:1.Polyphenol oxidase(PPO) is often regarded as a major factor resulting in time-dependent darkening and discoloration of Asian noodles and other wheat end products.The purpose of this study was to investigate the effect of genotype and environment on polyphenol oxidase(PPO) activity of wheat.The variability in whole-meal PPO activities was influenced by genotype,growing location.In total fifty-five wheat varieties sowed at three locations with three replications in two years were used to investigate the effects of genotype,environment and other quality characteristics on whole-meal PPO activity.The analysis of variance showed that whole-meal PPO activities were related to swelling power,peak viscosity,breakdown, with correlation coefficient -0.32,-0.18,-0.28.SDS sedimentation value,protein content,wet gluten,zeleny sedimentation value,pastingtemp,peaktime were correlated with whole-meal PPO activity,with r=0.20,0.28,0.28,0.24,0.27 and 0.21,respectively.Significant negative correlations were found between PPO activities and yellow pigment content,alkaline water retention capacity,hardness,though viscosity,final viscosity and setback.2.Thirteen wheat cultivars and advanced lines were sown in three locations for two years were used.The results showed that effects of environment on peak time and pasting temperature were greater than genotype,but effects of genotype were greater on peak viscosity,trough viscosity,breakdown,final viscosity and setback.The variation range of peak viscosity,trough viscosity and final viscosity was 2055.50～3935.50cp,1046.42～2589.00cp and 2412.00～341.50cp,respectively.The coefficient of variation of peak viscosity,trough viscosity and breakdown was 10.74%, 12.17%and21.25%,respectively.There exists significant difference among varieties except Peak time in RVA parameters and the relationship among Peak viscosity, Trough viscosity,Setback,Final viscosity,Breakdown,protein,wet gluten and Zeleny sedimentation are significantly negative.There is great difference between varieties in starch quality.Peak viscosity is an important index to evaluate wheat starch traits. Protein and starch qualities should be all paid great attention in the process of breeding varieties.3.Thirteen wheat cultivars and advanced lines were sown in three locations for two years to determine the genetics and environmental effects on 16 quality traits.The results showed that there were signficant differences of wheat quality parameters among wheat cultivars and planting sites.The variances of hardness,PPO activity, AWRC,yellow pigment content,breakdown were larger in differences environment; the variances of swelling power,final viscosity and peak viscosity were litter in differences environment.Effects of environment on pasting temperature,AWRC,peak time,protein content,wet gluten,PPO activity,yellow pigment content,swelling power,peak viscosity,breakdown,setback,Zeleny sedimentation value and hardness were greater than genotype,but effects of genotype were greater on SDS sedimentation value and final viscosity.Though viscosity is the most stability indices in the 16 quality traits.4.There were highly significant variances among these traits with little variances among starch pasting temperature,AWRC,pasting time and protein content,by unbalance analysis across multiple locations for two years.V1,V2 and V13 in Spring-water Group A,V2,V14 in spring-water group B,V2,V3 in winter-water group A and V2 in winter-water group B were better based on the stability of quality traits.For PPO,AWRC,pasting temp,peaktime,protein content,gluten content and hardness,there were large variance between years,however,larger effects of interaction between year by location for most traits,and larger effects of interaction between genotype by location for some traits.Therefore,the analysis among multiple years or locations was more important than that of one year or location.5.In the two successive wheat seasons(2005-2007),19 leading winter wheat cultivars and advanced lines,collected from Yellow and Huai River valleys facultative wheat zone,were sown at 4 sites(In each site,genotypes were sown in a randomized complete block design with three replications.) to investigate the current status of autumn-sown wheat quality in terms of genotypes and production locations, and to determine the effect of genotypes,locations,and their interactions on quality traits.Protein content were more influenced by location,the variance of location accounted for total variance of 58.53%,and genotype variance 19.88%.SDS sedimentation value was more influenced by genotype than by environment.Different quality traits showed different regular across multiple locations;SDS-sedimentation value,dry gluten,protein content and gluten content increased with the elevation of latitude,however,gluten index and peak viscosity decreased.Genotype,location, year and their interactions all had effects on all traits,although the relative importance of these sources differed.For SDS sedimentation value,AWRC,PPO,yellow pigment content,peak viscosity,though viscosity,breakdown,pasting temp,peaktime and hardness,genotype effects were larger than location,year,and all the interaction effects.The year effects were larger than those of genotype,location and and their interactions for gluten index,final viscosity and setback.The location was a large source of variation for such traits as wet gluten,dry gluten,protein content and Zeleny sedimentation value.