Research

OBJECTIVES
The International Centre for Pyrethrum Research will promote R&D aimed at improving the pyrethrin yield and quality from pyrethrum plants and at developing new and improved pyrethrin-based safe, ecological products.

PROJECTS
Listed below are projects currently ongoing at the labs of the groups particpating in the center.

Breeding & InvitroTech: Breeding and in vitro technologies to improve yield
Jing Mao (PhD student), ............, Prof Caiyun Wang (project leader) - HAU

Pyrethrum is an outcrossing self-incompatible plant species requiring special breeding programs to improve yield. In this project we aim to lift the current content from 1.6% average to 2.4% by classical breeding. Furthermore, we develop in vitro propagation methods to allow the rapid multiplication of desirable parent lines for seed production and we develop regeneration and transformation protocols aimed at possibilities to introduce or knock down specific genes in the pathway leading to pyrethrins, or compounds which are problematic in the production of the pure oil.
Funding organisation: Honghe Senju Biological Co. Ltd.

YieldGene: Determining the genetic factors controlling pyrethrin yield
Geert Stoopen (technician), Liping Gao (visiting postdoc HAU), Maarten Jongsma (project leader) - PRI
The yield of pyrethrins in pyrethrum ovaries may depend on both bottlenecks in the enzymatic pathway as well as on tissue specific limitations such as for example seed size. An important goal of the research is therefore to first find out what limits pyrethrin content in leaves and flowers. This will be done by microscopic and transcriptional comparison of pyrethrum leaves and flowers of accessions with extreme differences in content level.
Funding organisation: Honghe Senju Biological Co. Ltd..

INterSECT: Development of innovative methods for selecting and engineering natural resistance to thrips in ornamental and vegetable crops
Ting Yang (PhD 2008), Aldana Ramirez (PhD 2009), Liping Gao (visiting postdoc HAU), Jing Mao (visiting PhD student HAU 2006), Tila Menzel (MSc student), Geert Stoopen (technician), Maarten Jongsma (project leader) - PRI
Western flower thrips (Frankliniella occidentalis) and the associated TSWV transmission represent one of the largest single pest and disease problems in horticulure worldwide. This is due to the changing cultivation practices of ornamental and vegetable crops towards large scale, automated, (semi)closed cultivation. The only durable solution is the introduction of genetic resistance into crops. Such crops will be very competitive in the international markets, and this project will generate the tools to develop such corps. We aim to characterize the biochemical and genetic basis of existing resistance to thrips and TSWV transmission in cultivated and wild chrysanthemum (pyrethrum). For this we elucidate the pathway leading to both high jasmonate and pyrethrin production in the pericarp tissue surrounding the embryos. Jasmonate is a universal wound hormone inducing resistance to insects in all plants bases on the induction of many different defence genes. Pyrethrins take jasmonate as a substrate to form the most potent organic insecticide known today. Thus, this project is developing knowledge around both the most generic and the most potent botanical insect control agents known to date. The project focuses on the control of thrips and virus transmission, but the resulting principles will offer generic, durable solutions also for many other pest-plant problems which will be of additional benefit to the aims of TTI-GG.
Funding organisation: TTI Green Genetics project 1C001RP (2008-2012); www.groenegenetica.nl   


Pyrethrum trichome:
Tila Menzel (MSc student), Geert Stoopen (technician), Maarten Jongsma (project leader) - PRI

Pyrethrum seeds and leaves are rich in trichomes. In this student project we study the content and biological role of the glandular trichomes which can be found on both the leaves and seeds of pyrethrum
Funding organisation: PRI

Pyrethrum insect ecology:
Jing Mao (PhD student), Geert Stoopen (technician), Maarten Jongsma (project leader) - PRI

Pyrethrum plants are well known for their insecticidal constituents but so far never a proper biological study has been performed into the ecology of insects surrounding this plant. We are characterizing the volatile and non-volatile chemical constituents produced and emitted from leaves and flowers to relate this to the insect fauna found around these flowers in fields in both China and the Netherlands
Funding organisation: PRI

Pyrethrin extraction based on continuous pipe-type ultrasonic methods:
Senju Honghe Biological Co. Ltd.

1.1 The ultrasonic extraction technique yields results with the following advantages: Shortens the extraction time to one-sixth to one-twelfth of the time needed using traditional extraction methods; reduces the energy consumption to one-third to one-sixth of that of the traditional one; raises the extraction efficiencies.
1.2 The extraction capacity of one setup can reach 500kg/h, due to the continuous dynamic counter-flow principles of the extraction process. Thus, the production efficiency is notably raised, and particularly suitable for large-scale extraction.
1.3 The whole machinery realizes continuous operation and concentration control, reducing the labor intensity and number of workers involved. Furthermore is reduces losses in the course of production adding to the economy of production.
1.4 The pyrethrum marc processing unit provides the functions of trickling, squeezing and heating the solvents out from the sludge resulting in dried marc, reducing the loss of extracts, recovering solvents thoroughly with low energy consumption, which solves the difficult problems, which the traditional extraction machinery faced, of recovering solvents from the pyrethrum marc.
Funding organisation: Honghe Senju Biological Co. Ltd.

Pyrethrin extraction based on supercritical carbondioxide (SC-CO2) technology:
Senju Honghe Biological Co. Ltd.














SC-CO2 technology is superior to solvent based methods in terms of shortening cycle times, producing no environmental pollutants in the water or air and leaving no residues which exist in solvent-based recovery process. As a well known fire extinguishing agent, CO2 can ensure the safety in production in contrast to the inflammable solvent based methods. By applying engineered SC-CO2 technology to pyrethrin extraction, the market for products expands to the whole world with its high demand for high-concentration and high-quality pyrethrins. Pyrethrins extracted by this technology can be produced economically by Honghe Senju Biology and sold at competitive prices assuring Senju's leading position in this field.
Funding organisation: Honghe Senju Biological Co. Ltd.