Clean materials vital for domestic kaukau production

THE use of clean planting materials is paramount for improved agricultural production in Papua New Guinea.
This is true for sweet potato or kaukau.
The Highlands region is known for growing kaukau – as it is the staple food. In recent years, there has been a growing trend in commercial production by smallholder farmers, targeting urban markets, particularly Lae and Port Moresby.
The level of income fetched depends on tuber size, quality and other factors.
With declining soil fertility and other challenges, the harvesting of quality and marketable tuber size depends on the type of materials planted.
A NARI EU rural economic development programme (RED 2), which also prioritises kaukau as an agricultural innovations for improved livelihood in the Highlands region, has noted the unavailability (and lack of awareness) of adequate planting materials as a major production constraint.
More than 70 kaukau farmers Highlands-wide who participated in a survey indicated that there is inadequate supply and distribution of clean planting materials of kaukau which farmers can use for improved production.
Research by NARI has resulted in Pathogen Tested (PT) materials of kaukau, which can be used by farmers in their production systems for improved yield.
The PT process is a method of removal of viruses from the kaukau plants.
The Australian Government through the Australian Centre of International Agricultural Research had supported the PT work in the country. This work involved the introduction and establishment of a PT scheme to identify and remove viruses from kaukau.
Using the tissue culture laboratory facilities at Aiyura, which are jointly operated by NARI and the Coffee Industry Corporation, quarantine mesh igloos were erected for the virus testing phases of the scheme.
The PT scheme encompasses a number of activities. These include germplasm maintenance, foundation seed production, reselection, heat treatment, meristem culture, virus indexing using, indicator plants, Enzyme Linked Immunosorbent Assay (ELISA) and/or molecular methods. In the process of removing the virus from the plant, the PT scheme also ensures that plants are free from other diseases such as scab and scurf, and from pests such as gall mites and weevils whose eggs are deposited on the vines.
The kaukau industry in the Queensland State of Australia has been very successful in using the PT scheme to improve the yield and quality of tubers.
All major Queensland sweet potato growers are now using 100 per cent PT stock as their planting materials and have increased their marketable yields by 25-30 t/ha. The establishment of a similar scheme in PNG not only benefit farmers but also assist researchers and help improve the food security of our most valuable food crop.
Many PNG kaukau farmers have found the technology beneficial, after NARI and the Fresh Produce Development Agency have started distributing clean PT materials.
A group of mothers in the Whagi Valley of Jiwaka enjoy the PT technology as they continue to supply the local markets with good quality, marketable tubers.
Farmers in Hagen Central, Goroka and Tambul find the PT materials useful to support food security, income and livestock feed.
The PT technology offers huge opportunities for farmers.
There is a need for public offices and development partners to join forces in bringing the technology to the farmers.
Collaborations are required where resources allow to spread the message.
We need to improve farmer understanding on the importance of the production and use of clean planting materials for improved kaukau production in villages.
Kaukau farmers also need awareness in the areas of production of clean kaukau planting materials and field planting and management. Training and demonstrations are required on:
nLand preparation and planting;
nnursery and harvesting; and,
nPost harvest and marketing
Farmer awareness and trainings on best management practices and availability of clean and improved kaukau varieties have been conducted in the highlands and the lowlands of PNG and parts of Solomon Islands to help farmers identify quality planting materials and factors that contribute to low yield.
The RED 2 project has identified the kaukau value chain as a priority crop to work on with stakeholders on appropriate interventions.
It focuses on accelerating income generation from agricultural produce in the highlands which includes the kaukau supply chain and moreso help highland farming communities benefit from the adoption of new and emerging agricultural technologies.