Studies On Cutting Propagation Techniques And Its Rooting Mechanism Of Carya Illinoinensis

Pecan(Carya illinoinensis) is an important multipurpose tree species. It is difficult for cuttings rooting. Cuttings treatment technology, anatomical observation, physiological parameters measuring technology and MALDI-TOF-MS are used to explore pecan adventitious root formation mechanism. The main results obtained are as follows:1. When the external environment temperature control 15℃, soil temperature control 25~30℃, the best treatment is a concentration of ABT-1 500mg/L of rooting after soaking 6h. The rooting rate can reach 87.8%.2. The hardwood cutting rooting process of pecan can be divided into five periods: 10~20d as callus induction period, 20~30d as callus formation stage, 30~40d as the formation of adventitious roots, 40~50d as the large-scale form adventitious roots of cutting, after 50 d as the adventitious root elongation.3. The paraffin results showed that the adventitious roots developed from callus, which mainly originated from parenchyma cells of cambium and vascular ray.4. Cutting phloem treated by NAA is different from water treatment in the rooting process and Endogenous Hormone Content and Activities of Enzymes significantly. The results showed that: adventitious root formation process requires large amounts of soluble sugar, starch and soluble protein. Higher concentration of IAA could promote the formation of adventitious roots. Higher concentration of ZR promoted callus formation and adventitious roots elongation growth. Higher concentration of GA could restrain it. High SOD activity could improve cuttings resistance. High activity of POD promoted cuttings callus formation and adventitious root formation. High activity of PPO was in favor of the formation and elongation of adventitious root cuttings growth.5. The expressed proteins during the adventitious rooting of pecan hardwood cutting were identified and analyzed by MALDI-TOF-MS to evaluate its rooting mechanism. We found 48 differential proteins, of which 18 proteins were analyzed by peptide mass fingerprinting homology. The result shows that differential proteins, including energy metabolism proteins, adversity stress proteins, vsignal transmission proteins, expressed during the adventitious rooting.