Barley Differential Expressed Gene Analysis Between Parents And Hybrid

Heterosis is a very important biological phenomenon that is widespread in the biological, it is an important way to improve quality, enhance resistance and increase the crop yield in the improvement of crop varieties, and has achieved good economic benefits and social benefits in many crops such as rice, corn, rape. In recent years, the emergence and wide appliance of molecular markers have powerful impetus on the research of crop heterosis. In this paper, Using cDNA-AFLP technique to examine4barley sterile lines,2restorer lines and8hybrids combined (in NCⅡ design) from them, we study the different expression gene between the parents and their hybrids,and combine with the field agronomic characters of test materials:heterosis characteristics, combining ability and genetic parameters:Discussing the relation between genetic.differences and heterosis in the level of expression of gene, the difference fragments were recovered, and then amplified again, cloning, sequencing. The main results are as follows:1. The parents in most traits have significant genetic differences, heterosis exists widely in the main agronomic traits and yield traits of F1, most of the traits have superiority from mid-parent (Hm) and show significantly positive. However, the significant emergence rate of superiority over better-parent is only29.6%, and its range is from0%to50%. Parents have highly general combining ability, most traits of which have highly broad heritability. So, the recommended combination of strong advantages are the86F098×2001-1705R, hu1154X2001-1705R, the combination of weak advantage are86-166×2001-1758R, mian684×2001-1758R.2. The different expression gene between the parents and their hybrids were analyzed by the cDNA-AFLP analysis system. The result indicated that seven types of spectrum were obtained between parents and their hybrids, which were co-expression type (P1P2F1), P1expression type (P1), P2expression (P2), F1expression (F1), P2F1type (P2F1), P1F1type (P1F1) and P1P2type (P1P2). The difference spectrum were summarized for4expression pattern, which were single dominant expression type including P2F1and P1F1, single silence expression type including P1and P2, hybrid enhanced expression type F1and hybrid silence expression type P1P2.3.256pairs of primers are used to selective amplify the material testing, calculate out7901readable bands, among them are4611difference bands, the rate of variation is58.4%, there are obvious differences in gene expression between the hybrid combinations and parents. In eight different groups of parental and hybrid combinations256pairs of primers amplify into47150co-expression bands and11665difference bands.the rate of variation is19.8%. Among them the co-expression and single-parent dominant expression occupy the larger number of bands, respectively account for80.17%and11.34%, indicating that the dominant effect and additive effects are the main parts of the heterosis advantage. The expressive types of F1hybrids accounts for1.76%, indicating superdominant effect also plays a role in the heterosis effect. It can be seen that heterosis is the common result of dominant effect, additive effect, and superdominant effect.4. The BLAST results show that the main function of these differentially expressed cDNA fragments relate to:improve the efficiency of photosynthesis and carbohydrate transport, participate in the regulation of plant growth and development and anti-aging metabolic respect, enhance resistance to drought and frost resistance aspects of adversity stress. These genes may be associated with the formation of barley heterosis.