Conservation of genetic resources vital

Editorial

STATISTICS from the Food and Agriculture Organisation (FAO) of the United Nations show that over the period 1995-2001, production of staple root and tuber crops in PNG grew only by 6.5 per cent while the population grew by 15 per cent over the same period. There is also evidence to show that PNG and many other Pacific countries are in food deficit and are exposed to food insecurity.
That means the future of PNG’s food security could be at stake. The national population is steadily on the rise at a rate of 2.3 per cent per annum. With the current population of around eight million people, more food is needed for this growing number of mouths. So what are the common foods that the bigger fraction of eight million people eat? No doubt, they are the root and tuber crops, although cereals and grains (eg. rice) are important.
Such root and tuber crops include sweet potato, taro and yams. These are the stable foods for more than 85 per cent of the population who live in rural areas. They engage in subsistence food production to meet their daily requirements, with surpluses sold at local markets for cash income. But over the years, crop yields have remained almost static or have declined in some areas where population pressures are high.
The genetic resources existing under in situ (on-farm and in the wild) habitats are also depleting rapidly. Reasons, among others being the environmental destruction through logging activities, agricultural development, trade-related policies, mining activities and natural catastrophes such as floods, landslides, earthquakes, droughts, fires and cyclones.
Consumer preferences have changed market demand and this has also been responsible for the genetic erosion of landraces and farmer cultivars. Climate change is another potential cause of genetic erosion as it poses further threats to the survival of genetic resources.
The challenge of producing sufficient food for the nation now remains a great concern for the government and the people. PNG and many other Pacific Island countries have been identified by FAO as having poor food security status. This has been shown by low food production and productivity, increased volumes of imported food, a decline in purchasing power and indicators showing poor health and nutrition.
On the other hand, PNG has a rich diversity of plant genetic resources. PNG is home to many exotic and under-utilised fruit and nut species such as ton (Pometia pinnata), galip nut (Canarium indicum) and traditional vegetables such as pitpit and tulip.
It is also a rich haven for crop genetic resource diversity and the centre of origin for ‘noble cane’ (sugar cane) and winged bean (as bin) of New Guinea. Besides these, the nation is the secondary centre of diversity for sweet potato, taro, banana, yam, cassava and aibika. The diversity of these crops includes more than 1000 sweet potato, 800 taro, 200 banana, 300 yam, 70 cassava and 100 aibika varieties currently available.
Additionally, PNG is blessed with a broad genetic base of food crops that provides for tolerance against major pests and diseases. This means that crops are at less risk of being lost through attacks by pests and diseases unlike those with a narrower genetic base. A good example of a narrow genetic base was the Samoan taro diversity that had only three varieties of taro and was easily destroyed by taro leaf blight disease.
So how do we respond to issues of food security from the perspective of the surplus of genetic materials? Nari has taken up the challenge of developing its crop improvement programme to address the issues of low yield, poor quality and declining productivity of subsistence food crop production.
Crop improvement through the use of genetic resources offers opportunities for improving food security by overcoming constraints that limit food production. This will increase productivity, food quality and nutrition.
Nari’s current crop improvement programme involves evaluation and selection of indigenous varieties (germplasm), introduction of new and improved genetic materials (rice, peanut, maize, bananas, potatoes and mangoes) and the development of these materials through ‘conventional breeding’ or crossing two varieties of the same species to produce a ‘hybrid’ that has the desired genes for wanted traits. The conventional breeding program of Nari is currently focused on breeding taro lines that are resistant to taro leaf blight disease.
Over the years, the genetic diversity of the major staple food crops (sweet potato, taro, banana, yam, cassava, aibika, fruit and nut species and traditional vegetables) has been collected from farmers’ fields and market places. They have been individually characterised and evaluated for their qualities and conserved in fields on research stations.
Through the evaluation process, superior landraces or farmer cultivars are selected, multiplied and distributed to farmers throughout the country for production.
Nari has been entrusted by the government to look after the rich genetic diversity of food crop species in PNG. The institute has taken an active interest in increasing crop production and productivity through improving crop quality by using superior genetic materials from the national germplasm collections and gene-banks from abroad.
The conservation and safe keeping of the genetic diversity of food crops is important for food security, now and for future generations.
The country needs to conserve this diversity or the future of its food security could be at stake. Not only that but future generations could lose sight of the rich diversity that is found locally.