Brassica : Harvesting the Genome, Diversity and Products
The role of Brassica genomes in Agriculture and the Economy
Climate and Regional Adaptations
Brassicas are primarily adapted to temperate climates, and due to the inherent phenotypic plasticity, are well adapted to a range of intensive or low input cultivation techniques. The genetic diversity within the primary and secondary genepools includes gene variants (alleles) that encompass adaptations to abiotic (eg water, nutrient) and biotic (pests, pathogens) stresses, as well as considerable variation in secondary metabolites (oils, glucosinaltes, vitamins). There has been regional specialisation of crop types such as B. rapa vegetables in S.E. Asia, B. juncea oil crops in India. In general domestication has followed a typical path of selection of specialised forms followed by adaptive radiation and adoption amongst wider human populations.
Crops, Cultivated Area, Economy and markets
The total harvested area for Rapeseed (Canola) is 23,694,731 Ha (FAO, 2003), producing 35,931,452 Mt. This represents ?% of vegetable oil production. Of this, ?% is for human consumption.
Yield per hectare varies by ten-fold in different countries, reflecting different levels of inputs and efficiency of production. This highlights the scope for crop improvement, and yield will continue to be the primary focus of many crop improvement programmes. The relatively low harvest index (harvested : total biomass) of Brassica oil crops compared to other arable crops also provides considerable impetus for crop improvement.
Global market value
Value to farmers
Area Harvested Ha
Oil from B. napus, B. rapa and B. juncea is primarily used as an edible feed for humans or livestock. Oils are either used directly in cooking or processed into a variety of food products as a replacement for dairy-based fats in margarine. Residual meal contains valuable protein (~20%) which is used as livestock feed.
Added-value and non-food uses
Due to increasing pressures to reduce reliance on fossil-fuel carbon sources, Brassica derived is being adopted in some regions as a biodiesel engine fuel. Dependent upon fatty acid composition, other uses include lubricant oils and as a raw material for bio-composites and plastics.
Draft White Paper for Multinational Brassica Genome Project (MBGP); 12/01/2006