Clonal Selection Among/within Provenance/Families, Cutting Propagation And Cold Hardness Analysis On Platanus Occidentalis L. Introduced From United Stats Of America

The Platanus occidentalis L. Materials used in this research, were introduced from middle southern USA. Based on the performance of five year's multiple-sites field testing in central and eastern China, we made a primary Clonal selection among/within provenance and families. Based on that, we observed the variation both on the traits of rooting potential by cutting, and cold hardness characteristics for this clones of Platanus occidentalis L. The main conclusions are highlighted as follows:1. According to the evolution on the performance at five locations, superior families were selected upon H, DBH and Volume among 47 families (divided into 12 provenances) for different sites. There were 10 families for Songjiang (Shanghai), 11 for Zhenjiang (Jiangsu), 12 for Nanyang (Henan), 10 for Sixuan (Anhui) and 8 for Dongying (Shandong) to be selected. The H, DBH and volume growth increment for the total five locations were 1.46-44.27%, 11.37-89.07% and 28-219.31%, respectively. There were great variation among this selected families and great potential were there for individual tree selection. We put the selection standard for clone selection as 3 times deviation over the site family mean, and 211 trees were the candidates. The average volume increment for the candidates was 85.03% above the total volume mean, in which the highest was 113.17% (at Dongying) and even the lowest was 48.76%( at Nanyang) over the total mean.There were some trends indicated by the 51 selected families, of which there were about 70% came from the more Southern of Untied States. The lower latitude, the better performance for these introduced Platanus occidentalis L. seed sources on the testing sites in central and southern China.2. The results were shown that the rooting performance of the cuttings, which collected from the superior families, was varied not only by the position effect of the branches within clone, but also among/within seed sources and families. Based on the data of cutting tests, the most suitable parts for cutting was the middle part of the branch. The better one was the based part and the lowest rooting performance was the up part of branchThe main factors to influence cutting performance were the rooting lasting and the number of shorten root system establishing, but not the length of the longest root formation. The results of principle component and the dynamic cluster analysis, showed that there were 20 clones (occupied 34.48% of total clones), such as SJ8, DY2, ZJ14 etc. to root perfectly. But the 9...