木棉纤维的基本结构和性能

目的进一步完善木棉的组培快繁体系，实现木棉组培苗不定根的定向诱导，提高木棉生根苗的移栽成活率。方法以木棉组培丛生芽为材料，通过激素、纵向划痕和暗培养等3种处理促进根系诱导，比较不同处理下木棉组培苗的生根率、根系数量和移栽成活率，同时对生根过程进行显微观察。结果在单独添加NAA和IBA时，最高生根率分别为19.66%和39.15%；而NAA与 IBA组合处理的生根率可达95.80%，优于两者单独添加处理，且生根苗以1条不定根为主。纵向划痕处理以2~3个划痕效果较好，其生根率可达94%以上，生根苗以2条不定根为主。暗培养处理以6 d最佳，生根率为97.36%，生根苗以1条不定根为主。显微观察发现：木棉组培苗生根属于皮层生根类型。对1、2和3条不定根等3种类型的生根苗进行移栽，其移栽成活率之间无显著差异(P>0.05)，但生物量存在显著差异(P<0.05)，其中3条不定根的移栽苗生物量最大。结论本研究优化了木棉组培苗的生根条件，为木棉组培苗的移栽炼苗以及不定根的定向调控提供了理论参考。

In vitro rooting of cloned shoots in Pinus pinaster

PurposeTo further improve the tissue culture and rapid propagation system of Bombax ceiba, realizing the directional induction of adventitious roots of tissue culture seedlings of B. ceiba, and improving the transplanting survival rate of root seedlings of B. ceiba. MethodsThe clustered buds of B. ceiba get from the tissue culture were used as materials. The root induction was promoted by hormone, longitudinal scratch and dark culture treatments, so as to compare the differences in the rooting rate, root number of tissue culture seedlings and transplanting survival rate under different treatments. The rooting process was observed by microscope. ResultsThe highest rooting rate was 19.66% and 39.15% respectively when NAA or IBA was added separately, and the rooting rate was much higher when NAA and IBA used together, and the highest rooting rate was 95.80%, and the rooting seedling with one adventitious root accounted for the majority. In the treatment of longitudinal scratches, the effect of two or three scratches was better, and the rooting rate could reach more than 94%, with two adventitious roots as the majority. In dark culture, the best treatment was six days, and the rooting rate was 97.36%, and the rooting seedling with one adventitious root accounted for the majority. The microscopic observation showed that the rooting of tissue culture seedling of B. ceiba belonged to species that generate roots form cortex. In addition, there was no significant difference in transplanting survival rate among one, two or three adventitious of rooting seedling (P>0.05), but there was significant difference in biomass (P<0.05). Among them, the biomass of the transplanted seedling with three adventitious roots was the largest. ConclusionIn this study, the rooting conditions of tissue culture seedling of B. ceiba were optimized, which provided a theoretical reference for the transplanting of tissue culture seedling of B. ceiba and the directional regulation of adventitious roots.