Molecular Marker Development Of Falling Number In Wheat

Wheat is the major crop in the world.In international trade,the trading volume of wheat accounts for a large proportion.Wheat is affected by the monsoon climate,the phenomenon of sprouting occurs on the ear before harvest.The germination of wheat grains degrades the starch and seriously affects the quality of wheat.The activity of ?-amylase was enhanced in sprouted wheat seed,and it negatively affects the wheat falling number.The size of the falling number is an important basis for wheat grading,trading price and storage.In this paper,the ?-amylase gene and EST sequence in NCBI website were used to develop molecular markers related to wheat falling number.The main results are as follows:(1)Falling number were determined according to the AACCI/No.56-81.03(1972)international standard method.It were determined that the wheat falling number of 406 common wheat materials.And anova results show that there were extremely significant differences among different varieties in the population,and there was no significant difference between replicates,which could be used for developing markers.(2)It was aligned that the sequence of the ?-amylase gene ?-AMY1(NCBI gene accession number: KJ470678),?-AMY2(KX449614),?-AMY3(M16991)and EST(cv065403),and a total of 360 pairs of TRAP primers were designed.A total of 20 wheat varieties with extremely high and low falling number were used for primer selection.Then,20 pairs of primers were screened out from 360 pairs of primers,which showing high amplification efficiency,good repeatability,clear bands and easy discrimination.A total of 187 loci were amplified by 20 pairs of primers.There were 68 polymorphism locus and 173 bands.The amplified polymorphism rate reached 38.93%,and the polymorphism information content was 0.56.(3)9 pairs of primers were screened out from 20 pairs of primers,and a total of 15 band patterns were amplified in 86 wheat materials,all of which were significantly correlated with the falling number of wheat.Among the four bands,there was a significant negative correlation with the falling number of wheat,and there was a significant positive correlation between the 11 band patterns and the falling number of wheat.(4)Using 320 wheat materials for validation,the results showed that the wheat falling number was significantly positively correlated with the D band pattern of the primer AMY3FX2-15,and the E band pattern was significantly negatively correlated.The wheat falling number was significantly positively correlated with the F band pattern of the primer EST2-1,and it was significantly negatively correlated with the C band pattern of the primer EST2-10 and significantly positively correlated with the A band pattern of the primer AMY1FX7-12,and the B-band pattern was significantly negatively correlated.What's more,it was significantly negatively correlated with the B-band pattern of the primer AMY3FX7-6.The TRAP markers AMY3FX2-15,EST2-1,EST2-10,AMY1FX7-12,and AMY3FX7-6 developed in this paper can be used for molecular marker detection of wheat falling number.