Study Of Nitrogen Utilization Efficiency And Related Enzyme Activities In Wild Emmer And Its Introgression Lines With Common Wheat

Nitrogen use efficiency of wheat is mainly determined by genotype under the same cultivation conditions.Excellent genetic improvement is conducive to breeding more efficient nitrogen use varieties.Wild emmer wheat?Triticum turgidum ssp.dicoccoides,AABB,2n=4x=28?has abundant and excellent genetic resources.It is hopeful that its excellent genetic genes would be introduced into common wheat through wide hybridization.In this study,the nitrogen utilization and related enzyme activities of wild emmer D1 and D97 as male,common wheat variety Chuannong 16?CN16?as female and their introgressive lines(?F₁₂)were measured and analyzed to investigate the improvement potential of nitrogen utilization on common wheat by wild emmer.The main results are as follows:1.The results of agronomic traits analysis showed that 20%,66.7%and 86.7%of the 15 introgressive lines of D1 were significantly higher than their female CN16 in effective tillering,spikelet number and 1000-grain weight respectively,while 13.3%of the introgressive lines of D1 had significantly shorter plant than CN16.33.3%,66.7%and 100%of the six introgressive lines of D97 were signifiantly higher than their female CN16 in effective tillering and spikelet number,and 1000-grain weight,respectively.6 introgressive lines of D97 had similar plant height to their female CN16.2.The grain nitrogen and grain protein content of 21 introgression lines and their male D1 and D97 were significantly higher than those of their female CN16.Among them,99.3%and 66.7%of D1 introgression lines had higher grain protein and nitrogen contents than their parents CN16,while 100%and 50%of the introgression lines from D97 had higher grain protein and nitrogen contents than their parents CN16,respectively.3.The nitrogen content in both stems and leaves of both 21 introgression lines and their parents decreased,while in panicles increased with different growth stages.Nitrogen content in both stems and leaves of both the males D1 and D97 and their 21introgression lines was significantly higher at heading stage,while significantly lower at maturity stage than that of CN16.On the contrary,nitrogen content in panicles was significantly lower at heading stage,while higher at maturity stage than that of CN16.The peak of nitrogen content in leaves from all of the 24 tested materials was at heading stage.Correlations analysis showed that nitrogen content between leaves and stems during grain filling were significantly positively,while negatively correlated with that in panicles.In addion,the nitrogen content between panicles and stems was significantly positively correlated at flowering stage.4.The nitrogen translocation rate and nitrogen contribution rate in he tested organs of the tested 24 materials were decreased with growth and development stage.The nitrogen translocation rate and contribution rate of the tested 24 materials were leaf>glume and spike axis>stem except for the two introgression lines BAd164-4and BAd27-4.The nitrogen translocation rate and contribution rate of leaves,glume and spike axis,stems of 60%,86.6%,73.3%,50%,83.3%and 83.4%from the introgression lines D1 and D97 and their male parents D1 and D97 were significantly lower than that of CN16.5.The peak of NR activity and GS activity in flag leaf from all of the 24 tested materials was at flowering stage.And the NR activity and GS activity of the tested 24materials were decreased with growth and development stage.The NR activity and GS activity in growth and development stage of the high-protein strains of introgressive lines from D1 or D97 and their male parents D1 and D97 were significantly higher than those of CN16.6.There were significant negative correlation among grain protein content,grain nitrogen content,plant nitrogen content,NR activity with nitrogen translocation rate or contribution rate.But there was a significant positive correlation between grain protein content,grain nitrogen content,plant nitrogen content and NR activity,while the GS activity was only positively correlated with NR activity.7.There were no significant differences at different nitrogen supply levels in grain nitrogen content,grain protein content,organ nitrogen content,NR activity and GS activity of both the males D1 and D97 and their 21 introgression lines,but the values of CN16 in different nitrogen levels were significantly different.The values of7 introgression lines were significantly higher than those of parents CN16 at low nitrogen level.It can be seen that had strong tolerance to low nitrogen of both wild emmer wheat and containing the wild blood offspring introgression lines.