Seed Shattering And Its Related MADS-box Genes In Elymus Nutans

Seed shattering is a common characteristic in forage grasses. It seriously affects the seed yield and quality, resulting in huge economic losses. In this paper, the variation of seed shattering within population of Elymus nutans were evaluated for 3 years. One shattering-related gene (EnWM8) in MADS-box gene family and 2 housekeeping genes (EnACTIN and EnGAPDH) were isolated from E. nutans, and analyzed using bioinformatics method. The results are basis for breeding of the anti-shattering and research on the mechanism of seed shattering in E. nutans. The main results are as follows:1. Twenty four days after anthesis and 39.45% moisture content of seeds are the best time for seeds harvest in E. nutans. There were significant variations of the shattering rates within E. nutans population, averaged from 0 to 68.42% from 2008 to 2009. Seeds with different shattering levels have been collected, and planted in the greenhouse and field for evaluation.2. The abscission layers in seed pedicel and spikelet rachis in wild E. nutans were observed under electron microscopy. There is a circularity structure composed of dense cells at the edge of the abscission layers in spikelet rachis, but not in seed pedicel.3. The full length of EnWM8 gene was isolated from E. nutans and submited to GenBank (accession number is JF683846). EnWM8 is 1196 bp long in cDNA sequence and encoded 275 amino acids, which is the MIKC-type MADS-box gene and has some connection with flower development, fruit ripening and so on. The WM8 protein of E. nutans is a hydrophilic and basic protein with the molecular weight of 13 726.7 Da and the theoretical isoelectric point of 9.14. It is no membrane strucure and mainly located in the nucleus. There are manyα-helix, random coil and extended strand structures.4. The housekeeping genes actin and glyceraldehyde-3-phosphate dehydrogenase fragment were isolated from E. nutans, named as EnACTIN (GenBank accession number is JF683844) and EnGAPDH (GenBank accession number is JF683845) respectively.