How does water supply affect Taraxacum koksaghyz Rod. rubber, inulin and biomass production?

• An irrigation trial of Taraxacum koksaghyz R. with three irrigation regimes was assayed in a field in Northern Spain during 2010.
• Measurements of rubber and inulin content, biomass production and morphological aspects were taken.
• The effects of water supply on biomass production, inulin and rubber contents and on some other morphological characters were analyzed.
• A significant influence of the irrigation regime on rubber contents was detected and an optimal growth of TKS without irrigation was observed.
• A positive correlation between root and leaf weights and a weak to moderate negative correlation between rubber and inulin contents were detected.

Taraxacum koksaghyz Rodin (TKS) has been many times proposed as an alternative source for rubber and inulin production, but it is not being used at commercial scale due to the excessive production and extraction costs. We have studied the needs of water supply to find the best conditions for optimum production in order to facilitate the establishment of TKS as a potential, natural and renewable source for rubber and inulin production. Three irrigation regimes, including two different dosages and a non irrigated control, were evaluated in a field trial in Northern Spain. Only a significant influence of the irrigation regime on percentage of TKS rubber contents was observed, while no significant effects on inulin contents, biomass production and other morphological traits were detected. Additional water supply for optimal growth seems not to be necessary for TKS optimum development under local weather conditions, but further studies at dryer locations should be performed. A strong positive correlation was observed between root and leaf dry and fresh weights and a weak to moderate negative correlation between percentages of rubber and inulin contents.