A study on the in vitro tuberisation of potato cv Mondial
Paper Presenter: Mariam Bakerally, Faculty of Agriculture
Daneshwar Puchooa, Faculty of Agriculture & Mariam Bakerally, Faculty of Agriculture
Potato is the fourth most important crop worldwide, after the cereals maize, wheat and rice (FAO, 2006). Besides being a food and feed source, the potato tuber acts as a propagule in the vegetative propagation of the plant (Fernie and Willmitzer, 2001). This member of the Solanaceae is an excellent source of carbohydrates. The protein content amounts to 2.1 % of the fresh weight. Moreover, the amino acids present coincide with human requirements. It is also rich in vitamin C and potassium (FAO, 2006).
Local potato production amounts to 13 000 t annually, satisfying only about half of the local consumption. Due to scarcity of land, potatoes cannot be produced in large quantities so that they are available during off-season as well. Thus, 11 000 t are imported annually to meet the local demand of 24 000 t per year (Ministry of Agro Industry and Fisheries, 2007). The Mauritian government aims to cut down import costs by launching the Cross Border Initiative Programme with FAO. Mozambique, the partner country, is providing 1500 hectares of land in the province of Manica for the plantation of potatoes, onions and manioc along with other cash crops in rotation. This initiative would satisfy the Mozambican and Mauritian markets. It also presents an opportunity for the set up of a powerful regional and international agroprocessing centre (Ministry of Agro Industry and Fisheries, 2008). Furthermore, the Ministry of Agro Industry and Fisheries is aiming at undertaking seed propagation programmes, with the participation of small growers, from mini and microtubers, to reduce dependence on seed imports and to attain self-sufficiency.
Microtubers have many advantages over other potato propagules. Being of small size, they facilitate transportation and are amenable to mechanisation during direct seeding. They can be produced in bulk in any season (Kanwal et al., 2006). Moreover, they offer flexible planting options as they can be stored for long periods (Yu et al., 2000). Microtubers produce seed tubers relatively fast by reducing the number of field generations required (Vasil and Thorpe, 1994). Another application of microtubers is in germplasm conservation (Donnelly, 2003).
Many varieties have been evaluated for microtuberisation but work on Mondial variety has not been reported. Thus, this variety was chosen for this project in an attempt to assess this genotype with respect to in vitro tuberisation.
The aim of the experiment was to study the effect of various sucrose concentrations on in vitro microtuberisation of potato cultivar Mondial. Explants (single nodes and whole plantlets) derived from potato single node cultures were cultured on modified MS medium supplemented with BAP (2 mg/L) at different sucrose concentrations (0, 3, 6, 9%). Maximum microtuber yield was observed with 6% sucrose whereas 3% sucrose showed maximum microtuber size after 7 weeks in culture. However, sucrose did not show significant (p>0.05) correlation with microtuber yield and fresh weight.
Keywords: in vitro tuberisation, microtubers, potato, sucrose