Wetzstein Hazel Y, Porter Justin A, Janick Jules, Ferreira Jorge F S, Mutui Theophilus M
Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, IN, United States.
Department of Horticulture, University of Georgia, Athens, GA, United States.
Front Plant Sci. 2018 Mar 27;9:358. doi: 10.3389/fpls.2018.00358. eCollection 2018.
Artemisinin, produced in the glandular trichomes of L. is a vital antimalarial drug effective against resistant to quinine-derived medicines. Although work has progressed on the semi-synthetic production of artemisinin, field production of remains the principal commercial source of the compound. Crop production of artemisia must be increased to meet the growing worldwide demand for artemisinin combination therapies (ACTs) to treat malaria. Grower artemisinin yields rely on plants generated from seeds from open-pollinated parents. Although selection has considerably increased plant artemisinin concentration in the past 15 years, seed-generated plants have highly variable artemisinin content that lowers artemisinin yield per hectare. Breeding efforts to produce improved F hybrids have been hampered by the inability to produce inbred lines due to self-incompatibility. An approach combining conventional hybridization and selection with clonal propagation of superior genotypes is proposed as a means to enhance crop yield and artemisinin production. Typical seed-propagated artemisia plants produce less than 1% (dry weight) artemisinin with yields below 25 kg/ha. Genotypes were identified producing high artemisinin levels of over 2% and possessing improved agronomic characteristics such as high leaf area and shoot biomass production. Field studies of clonally-propagated high-artemisinin plants verified enhanced plant uniformity and an estimated gross primary productivity of up to 70 kg/ha artemisinin, with a crop density of one plant m. Tissue culture and cutting protocols for the mass clonal propagation of were developed for shoot regeneration, rooting, acclimatization, and field cultivation. Proof of concept studies showed that both tissue culture-regenerated plants and rooted cutting performed better than plants derived from seed in terms of uniformity, yield, and consistently high artemisinin content. Use of this technology to produce plants with homogeneously-high artemisinin can help farmers markedly increase the artemisinin yield per cultivated area. This would lead to increased profit to farmers and decreased prices of ACT.
青蒿素是从黄花蒿的腺毛中产生的，是一种重要的抗疟药物，对耐奎宁类药物有效。尽管青蒿素的半合成生产已取得进展，但青蒿素的田间生产仍然是该化合物的主要商业来源。必须增加青蒿的作物产量，以满足全球对用于治疗疟疾的青蒿素联合疗法（ACTs）日益增长的需求。种植者的青蒿素产量依赖于由开放授粉亲本的种子培育出的植株。尽管在过去15年中，通过选育已大幅提高了植物中的青蒿素含量，但种子繁殖的植株青蒿素含量差异很大，降低了每公顷的青蒿素产量。由于自交不亲和，无法培育出近交系，这阻碍了培育优良F1杂种的育种工作。本文提出了一种将传统杂交选育与优良基因型的克隆繁殖相结合的方法，以提高作物产量和青蒿素产量。典型的种子繁殖青蒿植株青蒿素产量低于1%（干重），产量低于25公斤/公顷。已鉴定出青蒿素含量超过2%且具有诸如高叶面积和地上部生物量产量等优良农艺性状的基因型。对克隆繁殖的高青蒿素含量植株进行的田间研究证实，植株一致性增强，估计青蒿素总初级生产力高达70公斤/公顷，作物密度为每平方米1株。已开发出用于青蒿大规模克隆繁殖的组织培养和扦插方案，用于芽再生、生根、驯化和田间栽培。概念验证研究表明，就一致性、产量和持续高青蒿素含量而言，组织培养再生植株和扦插生根植株均优于种子繁殖植株。利用该技术生产青蒿素含量均一高的植株可帮助农民显著提高每种植面积的青蒿素产量。这将增加农民利润并降低ACTs价格。
