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Yam chemical composition

Physico-chemical characterisation of yam (Dioscorea alata L.) tubers from Vanuatu

V. Lebot*, R. Malapa1, T. Molisale2 and J.L. Marchand1

* CIRAD, P.O. Box 946, Port-Vila, Vanuatu, South Pacific
1 CIRAD, 72 Av. JF Breton, 34398 Montpellier Cedex 5, France
2 VARTC, P.O. Box 231, Santo, Vanuatu

*Author for correspondence (e-mail: lebot@vanuatu.com.vu)

Received 27 September 2004; accepted in revised form 4 February 2005

Genetic Resources and Crop Evolution (2005) 00: 1–10

Key words: Chemotypes, Dioscorea alata, Germplasm, Food quality, Starch

Abstract: The objectives of this study were: (1) to analyse the physico-chemical characteristics of 48 Dioscorea alata varieties representing a core sample of the Vanuatu national germplasm collection; (2) to relate those characteristics with the varieties eating quality; and (3) to assess the possibility of selecting varieties according to their chemotype. Overall, 331 accessions were collected from 15 different islands of Vanuatu, planted in an ex situ germplasm collection and described during 3 years. The 48 varieties included in the core sample were selected according to their island of origin, eating quality, tuber shape, tuber flesh colour and morphotype. Analyses of their tubers were made for percentage dry matter, starch, amylose, lipids, minerals, proteins, sugars and gelatinisation temperature range. Significant variation exists for each of these characteristics except for gelatinisation temperature. Varieties with good eating quality are characterised with high dry matter, starch and amylose contents. Chemotypes appear to be genetically controlled and further screening of germplasm and/or breeding will have to take into consideration these characteristics, important for farmers’ adoption.



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DIVA-GIS	Thursday, November 03, 2005 Posted 4:15 PM by Luigi Yam chemical composition Physico-chemical characterisation of yam (Dioscorea alata L.) tubers from Vanuatu V. Lebot, R. Malapa1, T. Molisale2 and J.L. Marchand1 CIRAD, P.O. Box 946, Port-Vila, Vanuatu, South Pacific 1 CIRAD, 72 Av. JF Breton, 34398 Montpellier Cedex 5, France 2 VARTC, P.O. Box 231, Santo, Vanuatu Author for correspondence (e-mail: lebot@vanuatu.com.vu) Received 27 September 2004; accepted in revised form 4 February 2005 Genetic Resources and Crop Evolution (2005) 00: 1–10 Key words: Chemotypes, Dioscorea alata, Germplasm, Food quality, Starch Abstract: The objectives of this study were: (1) to analyse the physico-chemical characteristics of 48 Dioscorea alata* varieties representing a core sample of the Vanuatu national germplasm collection; (2) to relate those characteristics with the varieties eating quality; and (3) to assess the possibility of selecting varieties according to their chemotype. Overall, 331 accessions were collected from 15 different islands of Vanuatu, planted in an ex situ germplasm collection and described during 3 years. The 48 varieties included in the core sample were selected according to their island of origin, eating quality, tuber shape, tuber flesh colour and morphotype. Analyses of their tubers were made for percentage dry matter, starch, amylose, lipids, minerals, proteins, sugars and gelatinisation temperature range. Significant variation exists for each of these characteristics except for gelatinisation temperature. Varieties with good eating quality are characterised with high dry matter, starch and amylose contents. Chemotypes appear to be genetically controlled and further screening of germplasm and/or breeding will have to take into consideration these characteristics, important for farmers’ adoption. * Comments: Post a Comment	Archive October 2002 November 2002 December 2002 January 2003 February 2003 March 2003 April 2003 May 2003 June 2003 July 2003 August 2003 September 2003 October 2003 November 2003 December 2003 January 2004 February 2004 March 2004 April 2004 May 2004 June 2004 July 2004 August 2004 September 2004 October 2004 November 2004 December 2004 January 2005 February 2005 March 2005 April 2005 May 2005 June 2005 July 2005 August 2005 September 2005 October 2005 November 2005 December 2005 January 2006 February 2006 March 2006 April 2006 May 2006 June 2006 July 2006 August 2006 September 2006 October 2006 November 2006 December 2006 January 2007 February 2007 March 2007 April 2007 May 2007 June 2007 July 2007 August 2007 September 2007 October 2007 November 2007 December 2007 January 2008 February 2008 March 2008 April 2008 May 2008 June 2008 July 2008 August 2008 September 2008 October 2008 November 2008 December 2008 January 2009 February 2009 March 2009 April 2009 May 2009 June 2009 July 2009 August 2009 September 2009 October 2009 November 2009 January 2010 RSS Feed Alternative feed Contact Tevita Something new: Agrobiodiversity Weblog: For discussions of conservation and sustainable use of the genetic resources of crops, livestock and their wild relatives. 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