Preliminary Study On Germplasm Resources Innovation Of Forage Species Within Chrysanthemum In Broad Sense

Chrysanthemum in broad sense is an important part of Anthemideae Cass..This study focused on the collection,preservation,propagation,polyploid breeding,cross breeding of Chrysanthemum in broad sense.Selection of advantageous forage species were also studied.It mainly focused on the key species of Chrysanthemum,Brachanthemum,Ajania and so on.Main results and conclusion are listed as follows:1.Experiments were conducted for the standardization of micropropagation and regeneration of Leucanthemelia linearis.Nodal segments were used as explants and cultured on MS medium and 1/2MS medium supplemented with different concentrations of 6-BA and NAA both in individual and in combined form for shoot inductions.The best result of primary cultural was MS medium supplemented with 0.5 mg/L 6-BA and 0.5 mg/L NAA.The best subcultural medium was MS supplemented with 6-BA+NAA at the concentrations of 0.5 mg/L and 0.2 mg/L respectively.For root induction and elongation,1/2MS medium plus 0.3 mg/L NAA showed an adverse effect.Callus was induced from nodal segments on MS medium supplemented with 0.2 mg/L 6-BA and 0.5 mg/L NAA,and plants regenerated best from these callus on MS medium supplemented with 1.0 mg/L 6-BA and 0.2 mg/L NAA.2.Seeds of C.mongolicum and Filifolium sibiricum were used as explants.The best callus induce medium for C.mongolicum was MS with 1.0 mg/L 6-BA and 0.1 mg/L NAA,the best callus induce medium for F.sibiricum was MS with 0.5 mg/L 6-BA and 0.2 mg/L NAA.The best result of subcultural medium for C.mongolicum was MS medium with 6-BA+NAA at the concentrations of 0.2 mg/L and 0.2 mg/L respectively,and for F sibiricum was MS medium with 6-BA+NAA at the concentrations of 1.0 mg/L and 0.1 mg/L respectively.The best root induction and elongation medium was 1/2MS medium plus NAA at the concentrations of 0.3 mg/L for both C.mongolicum and F.sibiricum.3.The seeds of diploid C.mongolicum,Opisthopappus taihangensis and C.lavandulifolium were treated with different concentrations of colchicine and treatments duration to induce polyploidy plants.Morphological comparison,chromosome counting and flow cytometry were used for identification of the plants.C.mongolicum had the highest doubling efficiency of 6%while treated with 500 mg/L colchicine for 6 hours.The observation of C.mongolicum's stomatal size and density showed that it was a good method for polyploidies acquisition.The observation of stomatal size and density could efficiently identify the suspect tetraploids of O.taihangensis and C.lavandulifolium.4.This research involved 6 generas,58 combinations and 6253 florets.395 seeds and 73 plants were obtained.Some important hybrids were identified by morphological and cytological.The hybrids were A.achilloides × O.taihangensis,A.achilloides × C.lavandulifolium,(C.oreastrum ×'Wandaifengguang')× A.fruticulosa,(A.khartensis × O.taihangensis)× 'Jinseqionglu','Jinseqionglu'×(A.khartensis × O.taihangensis),C.coreanum × 'Taihanglongqiu','Jinseqionglu' × C.coreanum.5.Four parents and seven hybrids of Chrysanthemum in broad sense which have the potential to be good forages were selected,and the nutrient contents were measured.Grey relational grade analysis were used to evaluate the materials.The results showed that 'Jinseqionglu' and the hybrid of Dendrathema oreastrum were qualified forage plants.The hybrids were worth utilizating in future evaluations and could increase the nutrient richness in natural pastures.