Genetic Variation Of Vernalization Characteristic And Photoperiod Characteristics Of Wheat Varieties In Henan Province

Wheat is one of the major grain crop in China.As a major agricultural province,Henan has not only high grain yield but also a large number of high-quality wheat varieties.The present study was carried out aiming at investigating the change trends of vernalization and photoperiodic characteristics of varieties bred in Henan Province in the past 70 years,and exploring the effect of different vernalization and photoperiodic types on the growth and development of wheat.In this study,with 30 cultivars planted in Henan Province in different years as materials of study,the following conclusions were drawn on the basis of vernalization segregation under indoor high temperature,photosensitivity segregation under continuous illumination,as well as observation of spike differentiation in field and analysis of yield data.1.A correlation analysis was performed on the relationship between effective accumulated temperature and seedling-heading period with vernalization and photoperiod segregation in main spike differentiation period of tested varieties.Corresponding results showed that the period sensitive to low-temperature vernalization in the process of young spike differentiation and development was predominantly distributed in the time before the double ridge stage,and the photoperiod mainly affected the time after the double ridge stage.2.There were multiple types of vernalization and photoperiodic response in the evolution of wheat varieties in Henan Province over the past 70 years.However,the evolution of vernalization characteristics showed the variation trend of increase-weaken-strengthen in winterness degree.The winterness varieties were concentrated in the 1940 s and 1950 s in the course of evolution,during which the two weak winterness varieties were the main cultivars in the middle and late 1950 s.Furthermore,the proportion of weak winterness varieties and springness-prone varieties increased greatly in the 1960 s,1970s and 1980 s.Meanwhile,semi-winterness varieties were dominant since 1990 s.In addition,the sensitivity of photoperiod characteristics showed a decreasing trend.In view of changes in photoperiodic characteristics of wheat varieties,the photosensitive varieties mainly appeared in the 1940 s and 1950 s.The insensitive varieties accounted for a large proportion in the 1960 s,while the insensitive and sub-insensitive varieties occupied the major proportion in the 1970 s and 1980 s.3.Genetic testing results showed that all of the tested materials were recessive at the VRN-A1 locus.The VRN-B1 loci were dominant only by Abo and Zhengmai 9023,but recessive in other varieties.All VRN-B3 loci were recessive.There were two dominant sites of VRN-D1 a and VRN-D1 b,and one recessive site of vrn-D1 in VRN-D1 loci,among which the dominant locus occurred before 1990 s,and the recessive locus was mainly in this century.All Ppd-A1 loci were recessive.Moreover,regarding the locus of Ppd-D1,Ppd-D1 b was dominant only in varieties of Hulutou,Dakoumai,Honghe Shangtou and Dakoumai,and the rest were all recessive,indicating that the main Ppd-D1 a locus was Ppd-D1 a in wheat varieties of Henan province.4.Comparative analysis of genetic testing results and species classification revealed that wheat varieties with Vrn-B1 and Vrn-D1 a genes were weak springness wheat.However,the cultivars could show various winterness types when all the vernalization loci were recessive or only Vrn-D1 locus was dominant Vrn-D1 b.With respect to the above,whether the cultivars belong to the springness or winterness type could be determined roughly by using the identified vernalization gene,which was still not conducive to the refinement of specific springness or winterness type.For photoperiod genes,the material was photosensitive variety when the Ppd-D1 locus was photosensitive gene Ppd-D1 b.When Ppd-D1 locus was the photoretardant gene Ppd-D1 a,it contained not only photosensitive materials but also three types of insensitive,sub-insensitive and sub-sensitive varieties.In other words,Ppd-D1 b could identify sensitive varieties,while Ppd-D1 a was not available for the identification of insensitive,sub-insensitive and sub-sensitive varieties.