Evaluation Of North-typed Populus Deltoides Marsh. Gene Resources For Breeding

As an important gene donor of many poplar varieties in the world, Populus deltoides Marsh. plays important roles in genetic improvement of poplars. Aigeiros gene resource is scarce in China. In recent years, a lot of P. deltoides Marsh. gene resources have been introduced to China. Full understanding of these gene resources would provide strong scientific evidence and proper germplasm for poplar breeding. This paper comprehensively analyzes and evaluates P. deltoides Marsh. gene resources from growth, photosynthetic productivity, water use efficiency and nutrient use efficiency for the first time. The main results are described as following:1. Abundant variation of growth, photosynthetic productivity, WUE and NUE are found in among different genotypes in the same provenance and among different provenances of North-typed populus deltoides Marsh, which is to provide a basis for breeding parents in the provenances and individuals levels.2. The traits of North-typed populus deltoides Marsh. are closely related to growth, including total leaf area, leaf number, leaf number growth rate, internode length, respiration rate, N transfer rate, N content in leaf & WUE in the suitable growth period. They can be used as selection index.3. According to comprehensive evaluation, the superior gene resources of North-typed populus deltoides Marsh are as follows:high growth are M-6, Q-1, Q-5, M-5, Q-7; high growth and photosynthetic productivity are M-6, Q-1, Q-2, M-5, Q-5; high growth and WUE are Q-5, Q-1, W-9, M-5, Q-7; high growth and NUE are Q-9, Q-5, Q-3, Q-8, Q-1.4. Based on the analysis of principal components, clones M-6,Q-5,Q-1,Q-2 and Q-9 with high growth and high environmental resources use efficiency were ultimately selected. After further tests to observe, they would be directly applied.