Study On The Introduction, Progenitive Technologies And Cold Resistance Of The Cedrus Spp.

According to the stock of Cedrus deodara (Roxb.)Loud., the cion and hard branch of Cedrus libani Loud., the asexual reproduction characteristics of Cedrus libani Loud. were studied on the condition of field. In addition, the cold resistance of seven varieties seedlings about Cedrus libani Loud., Cedrus atlantica Manetti., and Cedrus deodara (Roxb.)Loud., which were grown in pots containing soils, were studied. The results of the experiment were as follows:(1) For the grafting of hard branch about Cedrus libani Loud., the best means was the cleft joint imbedding soil, and its survival rate could get 53.3% , meanwhile other ones were all under 13.3%. For the grafting of tender branch, compared with the 4 methods: the conjunction marrow cambium, the cleft conjunction imbedding soil, the ventral conjunction, and the incisal conjunction, their survival rate were 71.0%, 55.0%, 32.0% and 15.0% respectively.(2)The studies on the cuttage of Cedrus libani Loud. were indicated that the highest of rhizogenic rate was the 12# treatment, and its rhizogenic rate was 69.2%, but the 16# treatment was no root. The longest of average root length was the 4# treatment, because its length could be 5.7cm , and the longest root even reached 23.3cm;the shortest of average root length was the 15# treatment, because the root length only was 1.4cm. The Range Analysis of T Distributing showed that the effects of the quickset types and the hormone types on radication were great, whereas the effects of the hormone concentrations and the time of dipping in water on radication were not remarkable. The best assemble was the quickset's diameter was bigger than 0.3cm, the basal, ABT-1, 3×10-4g·L-1, and dipping in for 4 hours.(3)Under the cold stress, the studies on the cold resistance of 7 varieties indicated that the difference of chlorophyll content and conductance rate among seven varieties were both distinct. Under the condition of -5℃treatment, the chlorophyll content of Cedrus libani `brevifolia`, Cedrus deodara and Cedrus atlantica `Glauca` were lower, and took on depressed in early days and climbing later. With depression of the stress temperature, the other three ones, however, took on the depressed trend, and reached the lowest on -15℃.(4) With the temperature depressing, both the conductance rate and the MDA...