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11.
2013年进行了红松大田移植育苗试验,本文介绍了红松大田育苗的整地做床、栽培及苗期管理等技术。  相似文献   
12.
甜橙胚乳三倍体试管苗茎段及顶芽采用试管扦插培养难于生根,亦不能正常生长;而将其茎段和顶芽嫁接于试管中的砧木上,成苗率达90%以上。在含BA0.1mg/L的MT培养基中,每株嫁接苗形成3~4个芽,可作试管快速繁殖。嫁接苗移植于无菌土中,成活率高达95%以上。田间二重接可加速三倍体小苗生长。本方法为解决柑桔试管苗移植问题提供了一条新途径。  相似文献   
13.
AIM: To compare 2 environments, the subrenal capsule and oral submucosa, for producing well-formed teeth from mouse tooth germs and for exploring the ideal environment for tooth regeneration. METHODS: Two groups were set up. Group A was transplanted with the mouse embronic day (ED) 14.5 first mandibular molar tooth germs into the subrenal capsule, while group B was transplanted with the ED14.5 first mandibular molar tooth germs into the oral submucosa. After 3 weeks and 4 weeks, the host mice were sacrificed, and the transplanted explants were evaluated with morphologic observation, histological structures, hardness and elastictic modulus tests, and chemical compositions. RESULTS: (1) The explants isolated from both environments showed the tooth-like structures, but as to the group B, the crown was smaller, and the shape of the cusps was not significant. (2) HE staining showed that the dentin and enamel in group A were thicker than those in group B in which the ameloblasts and odontoblasts were differentiated not very well. (3) In the test of enamel hardness, only the hardness of 4 weeks in group B was lower than normal mouse tooth. In the test of enamel modulus, the elastic modulus of enamel in 3 weeks of group A was slightly lower than normal mouse tooth, but the difference was not significant.The elastic modulus of enamel in 4 weeks of group A and group B was significantly lower than normal mouse tooth and 3 weeks of group B. The hardness and elastic modulus of dentin in 3 groups was not significant. (4) Raman spectroscopy showed 2 groups grew in harmony in general, they all had the largest peak in the point of 961 cm-1, but the 3 weeks of group B had an obvious peak in the point of 2 947 cm-1. CONCLUSION: For the development of ED14.5 tooth germs, we obtain almost the whole tooth in subrenal capsule transplantation after 3 or 4 weeks. The buccal submucosa environment still has a certain influence on the tooth germ development, although there are some differences about the tooth development between this environment and subrenal capsule environment.  相似文献   
14.
采用双因素随机区组设计方法,以水稻品种黄华占为试验材料,分析在机插秧栽培模式下,不同的播期、插期组成的四种秧龄组合对产量性状和叶龄发生规律的影响。结果表明,随着播期和插期的推迟,产量水平呈下降趋势,其中以35d为最适秧龄,返青快、产量最高;且随着播期推迟,主茎叶片有减少趋势。  相似文献   
15.
琚慧媛  王嘉  李嫱 《安徽农业科学》2008,36(3):963-964,1149
[目的]研究辽宁地区玉米与紫花苜蓿间作的可行性。[方法]设置玉米、紫花苜蓿单作和间作3种种植方式,间作玉米采用控根育苗移栽,测定玉米和紫花苜蓿的株高、产量。[结果]间作玉米缓苗期、株高较低于单作,但抽穗后两者的株高差异不显著。间作紫花苜蓿的株高低于单作。1年生苜蓿与玉米相互间形成了一个相对合理的参数,两者的实际高度相近时,紫花苜蓿具有较好的收获量,可以刈割。间作玉米产量达12 190.5 kg/hm2,比单作玉米低11.4%,经济系数显著高于单作玉米。间作苜蓿的产量低于单作,但可以多次循环刈割。[结论]玉米、苜蓿间作增加了单位面积土地的生物量和产值,提高了综合效益,促进了辽北地区农业生态良性发展。  相似文献   
16.
不同栽培基质对非洲菊组培幼苗移栽成活率和生长的影响   总被引:4,自引:0,他引:4  
以非洲菊组培试管苗为试材。蛭石、珍珠岩、炭化稻壳、草炭土以不同的比例配成7种栽培基质,分别是A1(蛭石)、A2(珍珠岩)、A3(炭化稻壳)、A4(草炭土)、A5(1/2蛭石 1/2珍珠岩)、A6(1/2蛭石 1/2草炭土)、A7(1/3珍珠岩 2/3草炭土),进行非洲菊试管苗移栽基质的筛选试验。定期观测成活率、长势、平均株高及生长指标,地上部和地下部鲜重、干重,分析比较7种基质配方中对非洲菊试管苗移栽质量的影响。结果表明,非洲菊试管苗移栽基质以在A4(草炭土)、A7(1/3珍珠岩 2/3草炭土)的基质中生长较好最佳,其次,为A3(炭化稻壳)基质,但A3(炭化稻壳)成本较低,且较容易获得。  相似文献   
17.
Species can become regionally rare when limited by the availability of suitable habitats or by limited dispersal ability. We tested if the presence of a rare bryophyte species (Sphagnum angermanicum) was dispersal or habitat limited and at the same time investigated the possibility of establishing new populations of this rare species. Further, we tested how propagule (fragment) size and small scale disturbances affected establishment success. All field experiments were performed by artificially transporting propagules (of various sizes) to new and old sites for the species in Sweden.We show that S. angermanicum is dispersal limited on a regional scale, as no significant differences in establishment success were found between new suitable sites and old occupied sites. The larger the propagule the better was the establishment success; the best establishment success was found when transplanting whole shoots. Disturbances did not increase establishment success, in contrary, when compared to controls success was reduced by the more intensive disturbance treatments. We suggest that disturbance maybe more important for increasing direct dispersal than for making the microhabitat more advantageous for establishment. However, an intermediate disturbance, which slightly reduces the Sphagnum-community length increment, might also be beneficial for the establishment success of S. angermanicum propagules.The reasonably high establishment success of S. angermanicum propagules in new suitable sites suggests that artificial introductions of fragments could be considered as an active management regime for the species if the number of localities continues to decrease.  相似文献   
18.
[目的]筛选出较适宜铁皮石斛壮苗生根的培养基和移栽基质及移栽管理方式.[方法]以已分化出真叶的丛生苗为试材,通过研究不同植物激素配比和有机添加剂对铁皮石斛壮苗生根的影响,筛选出促进铁皮石斛试管苗快速生根和壮苗的培养基,同时对铁皮石斛试管苗的移栽进行全面研究,设置不同的移栽基质及移栽管理方式,以提高试管苗的脱瓶移栽成活率.[结果]适宜铁皮石斛生根的培养基为1/2MS+ 6-BA 0.5 mg/L+ NAA 1.0 mg/L+ IBA 2.0 mg/L;适宜铁皮石斛壮苗的培养基为1/2MS+ NAA 0.1 mg/L +6-BA0.5 mg/L;适宜铁皮石斛生根壮苗的有机添加剂为20%香蕉汁;适宜铁皮石斛移栽种植的管理方式为单栽,其中运用单栽管理方式适合铁皮石斛移栽种植的基质为1/3泥炭+1/3松树皮+1/3兰石,60d后成活率达80.0%.[结论]建立一套适合铁皮石斛壮苗生根与移栽种植的方法,为铁皮石斛的产业化大规模种植奠定基础.  相似文献   
19.
以“武运粳7号”为材料,通过不同稻作方式生产力比较试验,阐明了芽苗(乳苗)抛播稻茎蘖动态、干物质积累与分配、源库关系及产量形成特点,并提出了芽苗(乳苗)培育等关键栽培技术。  相似文献   
20.
草莓脱毒试管苗炼苗及移栽技术研究   总被引:9,自引:1,他引:8  
对草莓脱毒试管苗炼苗移栽技术及其影响因素进行了探讨研究,结果表明:培养瓶的开口方法、组培苗的根部冲洗、组培苗定植移栽的密度和方法,以及栽培棚室的温度、湿度等,均能影响草莓脱毒试管苗的成活及生长状况。通过试验,总结出一套适宜于草莓脱毒试管苗炼苗移栽的技术和方法。  相似文献   
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