黄毛草莓叶片离体再生及其同源四倍体的诱导

In vitro Regeneration From Leaf of Fragaria nilgerrensis and Autotetraploid Induced by Colchicine

为探究黄毛草莓叶片离体再生率及其同源四倍体的诱导效果,以黄毛草莓试管苗叶片和离体芽尖为材料,研究了不同激素配比对叶片离体再生的影响以及不同秋水仙素浓度和处理时间对其染色体的加倍效果。结果表明,黄毛草莓离体叶片在MS+1.0 mg·L-1TDZ+0.1 mg·L-1IBA的培养基上不定芽的再生率最高,为73.19%;0.15%秋水仙素处理草莓离体芽尖48 h诱导效果最佳,诱导率达13.33%,获得了经染色体计数确定为四倍体的株系12个,四倍体基因组DNA含量发生了倍增,染色体数量由14(2n=2x=14)条增加到28(2n=4x=28)条。与二倍体相比,四倍体黄毛草莓叶片更大更厚,颜色更深,叶形指数减小,气孔变大,叶绿素含量升高,整体植株生长势较强。黄毛草莓同源四倍体株系的获得为黄毛草莓的进一步研究奠定了基础。

In order to explore in vitro regeneration rate and autoteraploid inducing effeciency,the leaves of Fragaria nilgerrensis plantlet were used for studying the influences of different combinations of plant growth regulator on shoot regeneration,and the shoots were employed to investigate the effects of colchicines at different concentrations and treatment times on chromosome doubling. The results showed the best medium for in vitro F. nilgerrensis shoot regeneration was MS ＋ 1. 0 mg·L- 1TDZ ＋ 0. 1 mg·L- 1IBA on which the shoot regeneration was up to 73. 19%,the highest mutation rate was 13. 33% under treatment with 0. 15% colchicines for 48 h,12 autotetraploid lines were identified by chromosome counting. The genomic DNA content of autotetraploid lines was doubled and their chromosome number increased from 14（ 2n = 2x = 14） to 28（ 2n = 4x = 28） as well. Compared to diploid plants,the autotetraploid lines showed stronger growth vigor with bigger,thicker and darker leaves,smaller leaf index,bigger stomas,and more chlorophyll. The obtainment of autotetraploid lines laid a foundation for further utilization research on Fragaria nilgerrensis.