Assuring Reduced Variation in Commercial Crops (In vitro mass propagation experiences from Barbados and Caribbean plant tissue culture laboratories) Plants.

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Assuring Reduced Variation in Commercial Crops

(In vitro mass propagation experiences from Barbados and Caribbean plant tissue culture laboratories)

Plants as Providers of Fine Chemicals, Conference presentation, 29-30 August 2012, School of Chemistry, Bangor, Wales

Collin ScantleburyUniversity of the West IndiesCave Hill CampusBARBADOSE-mail: [email protected]

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• UAPS – Unit for Advanced Propagation Systems, Wye College, University of London at Wye near Ashford, Kent, UK

• BDD – British Development Division• ODA – Overseas Development

Administration

Plants as Providers of Fine Chemicals, 29-30 August 2012, School of Chemistry, Bangor, Wales

“Plant tissue culture and its applications in plant biotechnology”

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Applications of plant tissue culture to phytochemistry

• Via in vitro mass clonal propagation each single plant cell potentially can generate an entire new plant and thousands of clones

• Introduction of genetic/phenotypic variability in tissue cultured plants and associated different chemicals

• Direct gene cloning and host cell modification to increase access to target chemicals (molecular biology techniques)

• Concerted precautions to ensure clonal fidelity

Plants as Providers of Fine Chemicals, 29-30 August 2012, School of Chemistry, Bangor, Wales

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Caribbean Agricultural Research and Development Institute; University of the West Indies, Cave Hill Campus, St. Michael, Barbados www.cardi.org/. (Diamond Valley, St. Philip, lab)

Ministry of Agriculture. Graeme Hall, Christ Church, Barbados. www.agriculture.gov.bb. (Home Tissue Culture Laboratory, The Home Agricultural Station , St. Philip).

Plants as Providers of Fine Chemicals, 29-30 August 2012, School of Chemistry, Bangor, Wales

5Plants as Providers of Fine Chemicals, 29-30 August 2012, School of Chemistry, Bangor, Wales

6Plants as Providers of Fine Chemicals, 29-30 August 2012, School of Chemistry, Bangor, Wales

- A single plant from a remote forest

- Limited numbers in germplasm or genebank

- Research (field and laboratory studies) driven identification of a particular superior

plant species or variety (the athlete plant)

- Insufficient numbers for scientific field studies with replicated plots

7Plants as Providers of Fine Chemicals, 29-30 August 2012, School of Chemistry, Bangor, Wales

- Annual threat of hurricanes

Going bananas on the banana plantations

- Thousands of suckers required 875-1300/acre (2200-3300/hectare)

- Only sword suckers for planting (uniform)

- Uniformly growing and fruiting plants for better forecasting of harvesting

- Not seed-propagated like corn, wheat etc.

- Crop comprises a single variety not mixtures

- Black Sigatoka disease limits movement of germplasm across international borders

8Plants as Providers of Fine Chemicals, 29-30 August 2012, School of Chemistry, Bangor, Wales

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In vitro mass propagation process

Weaned and hardened vitro plants ready for field planting

Multiplying banana cultures

Plants as Providers of Fine Chemicals, 29-30 August 2012, School of Chemistry, Bangor, Wales

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macro & micro nutrients, vitamins, amino acids, sucrose, plant hormones, phytagel/agar, deionized H2O, HCl, NaOH,

(ethanol, NaOCl, fungicides, detergent/tween surfactant)

• cytokinins • auxins

Plants as Providers of Fine Chemicals, 29-30 August 2012, School of Chemistry, Bangor, Wales

IAA

IBA

NAA

BAP

Kinetin

TDZ - thiaduzuron

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Swelling and greening of meristematic buds within first week of explant initiation

Single shoot formation form (meristematic) bud or eyes

Single shoot ready for subculture or rooting (or splitting down the middle)

Plants as Providers of Fine Chemicals, 29-30 August 2012, School of Chemistry, Bangor, Wales

12Plants as Providers of Fine Chemicals, 29-30 August 2012, School of Chemistry, Bangor, Wales

Other Plant TC Applications for Phyto-chemistry

Cell and callus cultures for induced variationCell culture for genetic modificationCell culture for more ready access to target chemicals

Anther culture for polyploids

Somatic embryos for artificial seed

13Plants as Providers of Fine Chemicals, 29-30 August 2012, School of Chemistry, Bangor, Wales

Safeguards for Reduced VariationEach explant can produce thousands of offshoots but be conservative

In vitro multiplications rate may be variable so don’t stress the system

Use judicious levels of plant hormone (cytokinin, auxin, gibberillin)

Start clonal propagation process with proven mother plant (athlete plants)

Require field studies to ensure true- to- type-ness and not epigenetic/ephemeralphenotypic characteristic or environmental effects being observed

Field surveys of vitroplants are required to verify frequency of off-types/sports

Use preformed meristems (nodal and shoot tip explants) rather than leaf, stems,anthers etc. which involve callus stages

Selection of weaned and hardened plants (size, production dates, iso-lining)