Nowakowska Marzena, Pavlović Žaklina, Nowicki Marcin, Boggess Sarah L, Trigiano Robert N
Department of Entomology and Plant Pathology, Institute of Agriculture, University of Tennessee, Knoxville, TN 37996, USA.
Department of Genetics, Breeding, and Biotechnology of Vegetable Crops, Research Institute of Horticulture, 96-100 Skierniewice, Poland.
Plants (Basel). 2020 Jun 3;9(6):712. doi: 10.3390/plants9060712.
(Asteraceae), whorled sunflower, is a perennial species restricted to a few locations in the Southeastern United States. Habitat loss has caused to become rare, and since 2014, it has been federally listed as an endangered species. As a part of the recovery plan for the restoration and protection of , an efficient micropropagation protocol based on axillary shoot proliferation was developed. Various concentrations of 6-benzylaminopurine (BAP; 0 to 4.44 µM) were examined for their morphogenetic potential in the regeneration of six genotypes of from the nodal explants derived from greenhouse-grown plants. Both the BAP concentration and genotype had significant effects on the regeneration capacity of . Although the induced buds were observed on ½-strength Murashige and Skoog medium without plant growth regulators, a higher rate of induction and bud development were achieved on media with either 0.88 or 2.22 µM BAP, regardless of the genotype. Successful rooting of the induced shoots was achieved within four weeks after the transfer from the induction medium to the fresh ½-strength MS medium, but the rooting efficiency was dependent on the plant's genetic background. Regenerated plantlets, with well-developed shoots and roots, were acclimatized successfully to greenhouse conditions with a 97% survival rate. Simple sequence repeats (SSRs) markers were employed to assess the genetic uniformity of the micropropagated plants of . No extraneous bands were detected between regenerants and their respective donor plants, confirming the genetic fidelity and stability of regenerated plants. To our knowledge, the protocol developed in this study is the first such report for this endangered species.
菊科的轮生向日葵是一种多年生植物，仅分布于美国东南部的少数地区。栖息地丧失导致其变得稀有，自2014年以来，它已被联邦政府列为濒危物种。作为该物种恢复和保护计划的一部分，开发了一种基于腋芽增殖的高效微繁殖方案。研究了不同浓度的6-苄基腺嘌呤（BAP；0至4.44µM）对来自温室种植植物的节段外植体再生六种轮生向日葵基因型的形态发生潜力。BAP浓度和基因型对轮生向日葵的再生能力均有显著影响。尽管在不含植物生长调节剂的1/2强度Murashige和Skoog培养基上观察到了诱导芽，但无论基因型如何，在含有0.88或2.22µM BAP的培养基上诱导率和芽发育率更高。诱导芽转移到新鲜的1/2强度MS培养基后四周内成功生根，但生根效率取决于植物的遗传背景。再生植株的茎和根发育良好，成功适应温室条件，成活率达97%。利用简单序列重复（SSR）标记评估轮生向日葵微繁殖植株的遗传一致性。在再生植株与其各自的供体植株之间未检测到额外条带，证实了再生植株的遗传保真度和稳定性。据我们所知，本研究中开发的方案是关于这种濒危物种的首份此类报告。
