| Zelkova schneideriana Hand.-Mazz, is belongs to Ulmaceae,which is a good choice for high-end furniture materials, is excellent landscape trees, also plays an important role in cleaning the air, protecting and improving the ecological environment. However, because of over harvesting and lacking of protection of the wild, Zelkova schneideriana has been very scarced,it has.been listed as second-class protected plants. In order to understand the seed germination, master the general characteristics of seedling growth, to understand germination differences between different provenances。Provide the basis selection and large population of seedlings, to guide Zelkova schneideriana resource protection and utilization.This paper study five kinds of sources Zelkova schneideriana seed germination characteristics and seedling growth characteristics. Get the following main results:1. the biological characteristics of seeds of Zelkova schneiderianaAmerican seedsis the best of allsources,followed by Jiaxing. U.S. seed'sdiameter, longitudinal diameter, single grain weight, grain weight of seed and other seed sources have significant difference compared with the other seed sources.Seed purity determination that:the various provenances don't have significantly different, but the United States seed source is the highest, reaching 99.76%, followed by Jiaxing 98.58%, Wuhan 98.59%, Changsha 98.48%, Yuanjiang 97.75%The water content of all sources are:Jiaxing 15.9%, U.S.14.6%, Changsha, Yuanjiang, Wuhan were 13.3%,13.2%,12.0%; grain weight of Jiaxing, Yuanjiang, Wuhan, Changsha, the United States were to 11.86g,6.66g,9.70g,8.04g,15.58g.Water absorption characteristics of seeds:consistent absorption characteristics.of a variety of sources.is more or less. Absorption process can be divided into three phases:pre-4h is the first phase of rapid absorption phase; 4-36h is the second stage, decline of water absorption rate is in this stage, and gradually becomes more balanced; 36-72h is the third phase.The Order of reaching saturation water absorption is the United States, Jiaxing, Wuhan, Changsha, Yuanjiang.Viability of seeds:there are significant differences in seeds of different provenances. Viability of the United States seed sources have the highest proportion, 91%, followed by Jiaxing provenance,39%,24% of Wuhan provenance, Yuanjiang 3%, Changsha, all without provenance seed viability.The most suitable planting method is planting outdoor in autumn.The studies on Zelkova schneideriana planting methods on seed germination showed that the highest germination rate is planting outdoor in autumn, followed by the indoor cultivation, the worst for the planting outdoor in spring.Indoor germination rate in order:seed source of the United States, the highest germination rate,56%, followed by 28% in Jiaxing, Wuhan 5%, Yuanjiang and Changsha seed germination rate is 0;Outdoor germination rate of the order in autumn:the United States, the highest germination rate of seed sources,70%, followed by 55% in Jiaxing, Wuhan 12%,2% Yuanjiang, Changsha seed germination rate of 0;Outdoor germination rate order in spring:the seed source of the United States germination rate as high as 45%,22% in Jiaxing, Wuhan3%, Yuanjiang and Changsha seed germination rate is 0;In summary, the United States in all conditions, seed sources are the highest germination rate, followed by Jiaxing provenance, Wuhan, provenance, Yuanjiang provenance, Changsha provenance.2.Different treatments of Zelkova schneideriana on seed germination(1) cold stratification on seed germination of Zelkova schneideriana Cold stratification is effective way to lift lightly dormant seeds.60d cold stratification can significantly improve seed germination. The frist step of germination begin on the fourth day,41.5% germination rate, germination index was 10.88; but early sprouting of not for cold stratification seeds is in the eleventh day, the germination rate was 27.5%, the germination index 3.04.(2) BA, GA, NAA three kinds of hormones on seed germinationThere are many exceptions sprouted seeds with NAA treatment, not suitable for handling with Zelkova schneideriana seeds. BA and GA treatment can significantly increase the germination rate and germination energy. BA treatment makes the early sprouting of them compared to the control of 5 days in advance, the highest germination rate was BA500ppm treatment, the germination rate was 58.5%, respectively higher than those of 31%. The maximum germination potential treatment for BA50ppm,28%, increased by 17%; germination index was highest for BA500ppm treated up to 8.35, increased by 5.98. GA treatment could control the early sprouting of more than 2 days in advance, which GA100ppm treatment makes the germination rate was increased by 27%, germination index was increased by 3.69.BA deal with early sprouting of GA treatment than 3 days in advance, the maximum germination rate higher than the GA,4%, BA treatment were higher than GA, germination potential, germination index BA treatments were significantly higher than the GA treatment. In summary, BA treatment on the Zelkova schneideriana seed germination significantly, the most appropriate concentration of 500ppm, GA processing times, the most suitable concentration of 100ppm.(3) Cold stratification combined hormone treatment on seed germination of Zelkova schneiderianaAdopted the first cold stratification and then were used by BA, GA, NAA hormone treatment to handle seeds and found that the germination rate despite the slightly higher than the control, but did not reach significant level, and some but lower than the control. Note, seeds are not suitable for cold stratification combined with hormone treatment approach.3. Growth law of Zelkova schneiderianaYear germinated seedlings, growth in the year showed a "slow speed of a fast one slow one" trend. Early May, just after transplant seedlings, in a slow growth state; June early,seedlings reach the first rapid growth phase, the base A seedling growth rate of 0.47cm/d, seedling growth rate of the base B 0.29cm/d; June late to the end of July, high temperature impact on the growth of Zelkova schneideriana, growth has slowed, the base A seedling growth rate 0.26cm/d, base B seedling growth rate 0.28cm/d; the beginning of Augest to the middle of September, the base A seedling growth rate of 1.07cm/d, base B seedling growth rate 0.68cm/d; the middle of September to the end of October seedlings growing slowly, the base A seedling growth rate of 0.21cm/d, base B seedling growth rate 0.25cm/d; From the beginning of Noveber the seedlings stop growing. In December the average height for the base A, 88.18±4.97cm; base B, the average height was 67.53±5.09cm; there are significant differences. |
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