IN VITRO PROPAGATION OF BREADFRUIT

(Artocarpus altilis)

INTRODUCTION• In Vitro propagation (tissue culture) offers

prospects for rapid bulking up of Breadfruit planting material

• Usually vegetatively propagated using shoot or root cuttings and is essential for multiplication of seedless varieties

• Seeds: are rarely planted because of genetic variability and viability

• Research is being conducted at the FARC Tissue Culture Section, Réduit on Breadfruit “In Vitro Mass Propagation”

• Aims: Development of a commercially efficient Micropropagation Protocol for Breadfruit

• Expected to contribute to Local Sustainable Resources for Agriculture, Backyard Planting, Agro-forestry, Reforestation and ultimately Food Security

• Possibility for safe trans-boundary movement towards other countries interested in Breadfruit farming.

BENEFITS OF IN VITRO PROPAGATION

• FAST: More plants produced in a given period• Plantlets produced are genetically identical• Plants are produced under sterile conditions• Year round production of plantlets and not

dependent on external environment• Little space requirement for multiplication• Propagated material can be stored for a long

time• Little attention required for In Vitro cultures

between subcultures

• Requirement for specialised production facilities

• Propagation Protocol development is time consuming

• Plantlets obtained are small and juvenile• Genetic Variability can occur upon excessive

sub-culturing• Transitional phase required for adaptation of

plantlets to In Vivo conditions

CONSTRAINTS

GENERALISED METHODOLOGYThe General steps undertaken for the In Vitro

Mass Propagation protocol development were:

• Explant Collection and Surface Sterilisation• Establishment of Aseptic Cultures• Shoot multiplication • Rooting of shoots• Acclimatisation of Rooted TC Plantlets

Three Culture media have been Successfully

formulated at the FARC Tissue Culture Section based on Literature Leads available

These media are referred to as:1. Establishment Media (EM)2. Shoot Multiplication Media (SM)3. Rooting Media (RM)

TISSUE CULTURE MEDIA

INITIATION OF STERILE CULTURES• In vitro cultures were initiated from shoot buds collected from Réduit

• The buds were thoroughly cleaned and surface sterilised

• Cultures were then inoculated on Establishment Media

• Four trials were undertaken for development of an efficient Surface Sterilisation Protocol

• Success rate of the Selected Sterilisation Protocol was 85 % after modifications brought

• Contamination was mainly of bacterial origin

RESULTS and OBSERVATIONS

MORTALITY• Despite successful initiation of Aseptic Cultures

death of explants was a major drawback during trials

• Mortality from trials due to explant necrosis were principally because of:

1. Unsuitable Establishment Media2. Too Severe Surface Sterilisation Procedures3. Release of Phenolics by explants

MICROPROPAGATION• Mass production of Breadfruit plantlets was achieved

by transferring explants to Shoot Multiplication Media

SUBCULTURE• Sub-culturing of plantlets was done every 5-7 weeks• Axillary branches and buds were excised from main shoots and inoculated on fresh media

• An overall multiplication rate of 2.5-3 was observed

Growth Room Conditions• Cultures were kept in Growth Room at a temperature of 25oC and a 16hrs photoperiod

ROOTING OF PLANTLETS

• Rooted plantlets were obtained 5-6 weeks after inoculation on Rooting Media

• However, Root development on Rooting Media was observed for only about 60% of plantlets.

HARDENING• Rooted plantlets of about 5cm in height were selected for

hardening• Trials have been performed on different hardening media ( Soil,

Rocksand and Perlite)• Plantlets were kept in the ECU for adaptation to In Vivo

conditions

• Hardening is expected to last between 5-8 mths• Leaf Margins were smooth in In Vitro cultures

compared to the typical Lobed leaf morphology under In Vivo conditions

• Hardening could be considered successful as soon as plantlets develop the typical lobed leaves characteristic

FUTURE WORKS• Fine tuning and Optimisation of protocol• Reducing production time and cost of

plantlets production• Assessment of genetic fidelity of plantlets

after successive sub-culturing• Optimisation of conditioning & hardening for

higher % survival• In Vitro conservation of Breadfruit Varieties

THANK YOU FOR YOUR ATTENTION