For certain crops, selection and crossing are inadequate to introduce desired characteristics into a new variety. In such cases biotechnological methods, often referred to as genetic modification, may offer a solution.
Examples of this include the introduction of genes coding for BT-crystals to induce insect resistance in vegetables and cut flowers, and the improvement of sugar metabolism in tubers of potato and cassava through the introduction of genes which enhance the metabolic pathway of carbohydrates.
WSC is constructing genes which will provide new opportunities to plant breeders for improving crops. To introduce these genes in plants, WSC has developed many transformation and regeneration methods which are effective in more than 25 crops. A highly effective application of biotechnology is the identification of so-called molecular markers using DNA-analysis.
This method allows 'indirect selection' for a desirable plant characteristic. The method is of particular interest for characteristics which are difficult to evaluate in the field, such as resistance to a number of pests and diseases. In addition, molecular markers may be used to identify cultivars which are protected by plant breedersrights. Molecular marker systems have been set up by WSC for more than I 5 crops, including maize, tomato and lily. Tissue culture protocols have been developed for many crops and are widely applied in research and in commercial plant propagation. These protocols may use pollen to generate haploid plants, ovaries for in vitro pollination and fertilization systems, and bulb scales for in vitro selection of pathogen resistance.