Chemical Diversity of the Natural Populations of Dalmatian Pyrethrum (Tanacetum cinerariifolium (Trevir.) Sch.Bip.) in Croatia

Dalmatian pyrethrum (Tanacetum cinerariifolium (Trevir. ) Sch.Bip. ) is a plant species endemic to the east Adriatic coast. The bioactive substance of Dalmatian pyrethrum is a natural insecticide, pyrethrin, a mixture of six active components (pyrethrins I and II, cinerins I and II, and jasmolins I and II). The insecticidal potential of pyrethrin was recognized decades ago, and dried and ground flowers have traditionally been used in Croatian agriculture and households. A total of 25 Dalmatian pyrethrum populations from Croatia were studied to determine the pyrethrin content and composition, and to identify distinct chemotypes. The total pyrethrin content ranged from 0.36 to 1.30% (dry flower weight; DW) and the pyrethrin I/pyrethrin II ratio ranged from 0.64 to 3.33%. The statistical analyses revealed that the correlations between the percentage of pyrethrin I and of all the other components were significant and negative. The total pyrethrin content was positively correlated with the percentage of pyrethrin I and negatively correlated with cinerin II. The multivariate analysis of the chemical variability enabled the identification of five chemotypes among 25 Dalmatian pyrethrum populations. The chemical characterization of indigenous Dalmatian pyrethrum populations may serve as a good background for future breeding and agricultural exploitation.     

Cryopreservation of Chrysanthemum cinerariaefolium Vis. cells and its impact on their pyrethrin biosynthesis ability

An efficient protocol for cryogenic storage of high-pyrethrin-producing cell lines of Chrysanthemum cinerariaefolium is described. Optimal survival (92%) was obtained with cells precultured in 1/2 Murashige and Skoog nutrient medium containing 180 g ⋅ l^–1 sucrose for 30 days, then incubated in the same medium in the presence of 5% DMSO for 1 h in an ice bath, cooled slowly to –20°C and immersed for 30 min in liquid nitrogen. After cryopreservation, the cells conserved the same growth pattern, but displayed different biochemical properties. The subculture derived from the thawed cells was characterized by a lower chlorophyll content and a higher pyrethrin biosynthesis ability. Received: 17 February 1997 / Revision received: 27 May 1997 / Accepted: 17 June 1997     

除虫菊开花特性与适宜采摘期

除虫菊 (Pyrethrumcinerariifolium)是提取天然除虫菊酯的原料 ,植物体的各个部位均有除虫菊酯分布 ,最主要存在于头状花序 (简称花头 )的子房中 ,随着花蕾的孕育、开花直至种子 (瘦果 )成熟 ,子房壁导管的油腺也同时经历了发生、发展和分泌物转化的过程。直接反映在开花期的不同阶段所采摘的花头内菊酯含量的变化十分显著 ,为了进一步认识除虫菊开花期小花开放程度与菊酯含量变化的内在规律 ,把除虫菊开花期 (从孕蕾盛期到瘦果成熟 )划分成 8个阶段。通过样品测定 ,了解开花期花头中菊酯含量的变化状况和头状花序发育过程中小花子房的增长与干物质积累之间的关系 ,表明头状花序的小花开放至第 4至第 5阶段 ,即花头上管状小花开放初盛期至盛期时采摘 ,是获得最高生物产量和菊酯含量的最适宜采摘期。     

Effect of ethrel,chlormequat chloride and paclobutrazol on growth and pyrethrins accumulation in <Emphasis Type="Italic">Chrysanthemum cinerariaefolium</Emphasis> Vis.

Pyrethrins and flower yield of pyrethrum (Chrysanthemum cinerariaefolium Viz.) plants were determined after application of ethrel, chlormequat chloride and paclobutrazol. Ethrel at 50, 100, 250 and 500 mg l^−l produced a significant positive effect on pyrethrins level, decreased plant height, while 50 and 100 mg l^−l significantly increased fresh and dry flower yield. Chlormequat chloride at 1000 and 2000 mg l^−l and paclobutrazol (80 and 160 mg l^−l) increased pyrethrins level, single flower weight and decreased plant height and flower yield. ¹⁴C-acetate incorporation studies further substantiated positive effect of growth retardants on pyrethrins biosynthesis. The effect of growth retardants on pyrethrins seems to be mediated through its effect on biosynthesis.     

Rapid mass propagation of Chrysanthemum cinerariaefolium Vis. by callus culture and ability to synthesise pyrethrins

 Rapid mass propagation of Chrysanthemum cinerariaefolium from young flower heads was developed to compare the ability of callus, in vitro shoots and rooted plants, and original plants to synthesize pyrethrins. The ability to synthesise all six pyrethrin components increased with differentiation. Jasmolin II and cinerin II were the main products present in mother plant shoots, whereas pyrethrin I was the greater component present in callus and in vitro plants. Clonal propagation increased the pyrethrin I content compared to that of plant shoots and young flowers. Total pyrethrin content was the same in in vitro and plant shoots, but lower in these shoots than in young flowers. The pyrethrin I/pyrethrin II ratio, which is directly related to insecticidal activity, varied from 3.4 in in vitro shoots to 0.87 in mother plant shoots and young flowers. Received: 11 July 1998 / Revision received: 10 March 1999 / Accepted: 12 April 1999     

除虫菊发状根的诱导及培养条件优化

以除虫菊（Pyrethrum cinerariifolium Trey.）无菌苗为外植体,研究除虫菊发状根的诱导、培养条件优化,并对发状根中的除虫菊素进行检测和生物活性测定。结果显示,乙酰丁香酮能促进除虫菊下胚轴和子叶发状根的诱导,当乙酰丁香酮浓度为150 μmol/L时除虫菊下胚轴和子叶的诱导率为对照的2.29倍和2.66倍,预培养6 d时,下胚轴发状根诱导率为对照的2.25倍,发根农杆菌A4的诱导率均高于ATCC15834,愈伤组织较适合发状根的诱导,愈伤组织侵染后适合在无激素的MS培养基上进行发状根诱导,250 mL三角瓶中添加50 mL MS培养基较适合发状根的生长。对除虫菊发状根进行PCR检测发现,发根农杆菌含有的Ri T-DNA的rolB基因已整合进入发状根基因组中。通过GCMS检测发现,愈伤组织中除虫菊素的6种成分均未检测到,而发状根中检测到瓜菊素Ⅰ、茉酮菊素Ⅰ和茉酮菊素Ⅱ 3种成分,发状根对粘虫的拒食作用明显优于愈伤组织。本研究为通过组织培养方式生产除虫菊素奠定了基础。     

Identification and assay of pyrethrins in Chrysanthemum cinerariefolium calli

Summary Callus from four clones of Chrysanthemum cinerariaefolium have been investigated for pyrethrins biosynthesis. Calli from disc-flowers, bud-flowers, stems and leaves of clone HY D were cultivated. Best growth was obtained by initiating the culture on Murashige and Skoog medium containing 3% sucrose, 1% agar, 4 ppm -naphtoxy acetic acid (ANA) and 0.4 ppm 6- benzyl aminopurine (BAP) for 28 d, then transfering explants on i.e. at the beginning of the stationnary phase. Disc-flowers calli from two high-producers clones (HY C and HY D) and two low-producers clones (SY A and SY B) were also cultivated. Pyrethrin amounts found in callus cells showed a direct relationship between parental clone synthesis ability and callus cell production. Selection of high-producers clones is thus essential for optimisation of pyrethrin synthesis.