Tissue Culture And Nutrition Of Taxus Chinensis

The present experiment studied techniques for tissue culture of T.chinensis with mature seeds, apical buds and axillary buds collected from Mount Jinyun in Chongqing . Research work on the nutrition of T.chinensis was carried out at the same time. Following are the main results:1 .During the plant regeneration from mature zygotic embryos of T.chinensis, it was better to remove most part of endosperm away and then culture darkly in l/2BjSH and 1/2MCMSH medJunuwith 6BA and activated charcoal(AC). Thereafter, transferred zygotic embryos to 1/2B5SH and 1/2MCMSH added with AC for further development at photoperiod (16rrd~' in light and 8 in dark) after rooting. Individually/23.5% and 20.0% of zygotic embryos rooted. The results improved little the previous studies in rooting rate. The reasons perhaps mainly lie in the genetic characteristics of yew species and the regeneration may also be influenced by the removement of endosperm and the culture condition.2.The better time for collection of apical buds and axillary buds current year grow for tissue culture was from Augest to November. After sterilization with 0.1% HgCl2, we cultured them on B5SH and MCMSH with hormones or hormone-like chemicals (6-BA, IAA, IBA or NAA) and 0.2~lg'L"' AC. It was easy to induce buds but difficult to roots. In the process of rooting, how to cut down brunneus excretion and callus ramain unsolved.3-Concentrations of N, P, K, Ca, Mg and NO3"-N in the needles of T.chinensisvaried seasonally throughout the year. N, P, Ca were higher in Summer and Autumn while lower in Spring and Winter; the concentrations of Mg changed in accordance with Autumn>Summer=Winter>Spring; NO3--N in needles from March to July were high in the year. Monthly concentrations of P were very low and differed seasonally little compared with other nutritions. Obviously, the variations characterized with the nutrient elements and the climate in Chongqing.4.The changes of the contents of N, P, K in different directions generally followed the rule of SoutiP-East^West^North. The concentrations of Ca, Mg, NO3--N in different directions changed little.5. With the increacement of tree ages, the concentrations of N, P, K in needles were increased while Ca, Mg, NO3"-N were decreased and Mg varied slightly. The causes may associate with the absorbence, translocation and recycle of nutritions. Compared with positions, tree ages affected greatly on the concentrations of nutritents in needles.6.In trees of different ages, the concentrations of nutrients followed N>K> Ca>P>Mg> NO3'-N. We can thus conclud that T.chinensis need relatively more N, K and Ca. N, K and Ca fertilizers could be import to T.chinensis growing in acid purple soil. According to the seasonal variation of nutritents, it is better to fertilize T.chinensis at the end of Spring and at the beginning of Summer.