Posted 1:46 PM by Luigi
Was Papua New Guinea an Early Agriculture Pioneer?

By John Roach
for National Geographic News
June 23, 2003


Once considered a "Neolithic backwater" by archaeologists, Papua New Guinea is emerging as one of the handful of places on Earth where agricultural practices developed independently from other cultures.
The evidence, reported June 19 on the Science Express Web site by Tim Denham, an archaeologist at Flinders University in Adelaide, Australia, and colleagues, may put an end to a long-standing debate on the origin of agriculture in the swampy highlands on the island nation.

"People were definitely exploiting plants, including taro, at Kuk Swamp approximately 10,000 calendar years before present," said Denham. "There is then-evidence of banana cultivation from 6,950 to 6,440 calendar years before present."

Taro (Colcasia esculenta) is a tuber with edible leaves and starchy roots. It remains a staple in the Papua New Guinean diet today.

Prior to this discovery, many scientists regarded Papua New Guineans as passive recipients of domesticated plants and animals from Southeast Asia. But the dates for the rise of agriculture documented by Denham and colleagues predate the earliest known Southeast Asian influence by about 3,000 years.

Katharina Neumann, an archaeobotanist at Johann Wolfgang Goethe-Universität in Frankfurt, Germany, writes in a related Science perspective that "only a few regions were geographically suited to become the homelands of full agricultural systems. New Guinea seems to have been one of them."

Re-examination

Denham and colleagues base their conclusions about the gradual rise of Agriculture in Papua New Guinea on a re-examination of the Kuk Swamp excavation site in the Wahgi Valley.

The site was first investigated in 1966 with subsequent excavations in the 1970s, but the details of the finds were never fully published and the evidence for agricultural practices were inconclusive, said Denham.
"The most serious problem was the absence of any remains of the plants which had been hypothetically exploited," said Neumann. "This is for a large part due to preservation, like in other humid, tropical regions."

But Denham and colleagues were able to find plant residues in the soils and on stone tools. According to the analysis of these residues, the researchers conclude that the Papua New Guineans were indeed exploiting taro and banana.

The team also dated features consistent with the planting, digging, and tethering of plants and localized drainage systems to 10,000 years ago. Mounds constructed to plant water-intolerant plants such as bananas, sugarcane, and yams are dated to about 6,500 years ago.

Neumann said "careful documentation of the archaeological features with a large number of radiocarbon dates and recovery and identification of microscopic plant remains" allowed Denham and colleagues to document the gradual rise of agriculture in Papua New Guinea.

Denham described the agricultural setting of the Wahgi Valley at approximately 6,500 years ago as a valley floor carpeted in grasslands that were periodically burnt and the Kuk site itself as cleared plots perched on a wetland edge. On mounds constructed in the plots grew bananas, sugar cane, and yams. Taro would have filled the wetter ground between the mounds.

Societal Impact

To this day the island country between Australia and Southeast Asia does not fit models that try to link agriculture and the rise of civilization in terms of urban centers and social and political classes, said Denham.

"New Guinean societies are relatively egalitarian and characterized by the bigman institution whereby a man leads a community, or part of a community, largely through persuasion and prowess in particular activities," he said.

Leadership traits include the ability to talk, fight, produce, and maintain relationships of exchange. Exchange relationships were traditionally based on the trading of pigs, shells, and women but in modern times are being replaced by money and Western material goods, said Denham.

Neumann notes that the researchers do not resolve the question of how important agriculture was in relation to hunting and foraging, and thus it is possible that agriculture played only a minor role. For example, most of the plants found at Kuk are distributed in wild vegetation.

"But this does not diminish the value of the evidence for cultivation at Kuk," she said. "Agriculture and wild plant exploitation do not exclude each other. More and more scientists think that the development from foraging to farming was gradual and not a rapid revolution."

Posted 8:07 PM by Luigi
Recent News from SPC's Regional Germplasm Centre (RGC)

From Dr Mary Taylor, RGC Advisor, SPC

1. Four of the RGC's staff participated in a virus indexing workshop held in the Institute of Applied Science at USP. Suva. The resource persons were Associate Professor Rob Harding and Dr Peter Revill from QUT. QUT was funded by ACIAR to develop virus indexing technology for taro to support the AusAID funded TaroGen project. The aim of the workshop was to transfer this technology to the Pacific. The work was carried out in the laboratory which has been established by IAS in collaboration with SPC. SPC PPS has provided funds for equipment for this laboratory, and with the support of their virologist, Dr Richard Davies, the RGC staff will be able to carry out virus indexing in this laboratory in the future.

2. Earlier in the year (May, 2003) Dr Ian Godwin and Hunter Laidlaw from UQ were the resource persons for a workshop on DNA fingerprinting. UQ had been funded by ACIAR for the DNA fingerprinting work (microsatellites) on the taro accessions collected under TaroGen. This workshop was again transferring the developed technology to the Pacific. This workshop was in collaboration with the Department of Biology, but future DNA work will be carried out in the IAS laboratory.

3. Distributions of germplasm from the RGC have continued during 2003 with bananas to A. Samoa, bananas to Koronivia Research Station, Fiji, sweet potato and bananas to Kiribati, taro, sweet potato and banana to FSM, banana and yam to Guam, TANSAO taro to Maui Agricultural Research Centre, Hawaii.

4. Thirty cultivars of D. rotundata have been imported from IITA, Nigeria. These cultivars will be useful to growers because of resistance to anthracnose. Cultivars of D. rotundata distributed from the USP lab and evaluated in Samoa in the 90s performed well and were popular with growers. These cultivars will have to be screened for viruses prior to distribution.

5. Some success has been achieved in establishing a tissue culture system for kava and research is continuing to improve on these results. A decontamination technique has been developed that is achieving 70-80% clean cultures for one cultivar.

6. The RGC video has been completed and will be shown at some of the local secondary schools for evaluation. Copies will be made and will be available for distribution. Teaching notes have been prepared to accompany this video.

7. The RGC website has been launched.

Posted 9:18 PM by Luigi
Latest Kava Research

I've just received this message from Dr Diane Ragone of the National Tropical Botanical Garden:

The current issue of Herbalgram has an article on kava based on work that an NTBG team did in Samoa last year.

Lack of Evidence of Kava-Related Hepatotoxicity in Native Populations in Savaii, Samoa. Joan Borel; Paul Alan Cox, Ph.D.; Krisa Fredrickson; Diane Ragone, Ph.D.; Patricia Stewart, D.O.; Gaugau Tavana, Ph.D. 2003. Herbal Gram 59: 28-32.

Abstract: Kava has long been a symbol of respect and hospitality throughout the islands of Polynesia, western Melanesia and Micronesia. It has become popular in North America, Western Europe and Asia during the past two decades, that is, until recent reports about possible liver damage associated with kava. This study returned to the source, seeking evidence of liver damage in native Samoans who use kava informally and in ceremonies, and finding none.

On October 4th, Lyon Arboretum, Honolulu, is hosting a Hawaii Pacific Islands Kava Festival - a celebration of traditions:

http://kavaforum.org

http://kavafestival.org

Dr Skip Bittenbender, UH, sent the following articles dealing with the kava-liver controversy:
1. Peter A. Whitton, Andrew Lau, Alicia Salisbury, Julie Whitehouse, Christine S. Evans (in press) Kava lactones and the kava-kava controversy. Phytochemistry.
2. Stefan Russmann, Yann Barguil, Pierre Cabalion, Marina Kritsanida, Daniel Duhet and Bernhard H. Lauterburg (2003) Hepatic injury due to traditional aqueous extracts of kava root in New Caledonia. European Journal of Gastroenterology & Hepatology 15:1033–1036.

The paper by Whiton deals with lack of glutathione in ethanol or acetone extracts of kava and effect on amoebas . This paper cites the UH pipermethystine hypothesis but does not refer to it in explaining their results. The paper by Russman looks at two cases in New Caledonia where kava beverage led to liver problems and then follows with a survey of 27 regular kava drinkers. Their conclusions: the 2 liver problems were a idiosyncratic response that went away after kava use stopped. The regular users did not have liver problems but the kava might have induced increased liver activity to metabolize the kavalactones. This in turn might enhance side effects from other medications.

Posted 3:41 PM by Luigi
Taro Research in Samoa

The following article by Samisoni Pareti appeared 4 September 2003 in Islands Business Magazine.

The future of a research program aimed at assisting Samoa recover from the debilitating effects of the taro leaf blight (TLB) is in doubt now that funding will dry up at the end of the year.

Australia's international aid agency, AusAID, has been funding the taro research work based at the University of the South Pacific's Alafua Campus in Apia for the past five years. It is jointly implementing the program with the Secretariat of the Pacific Community (SPC).

"AusAID has funded this project for two phases, phase 1 (1998-2000) and phase 2 (2001-2003)," explains Tolo Iosefa, the local scientist coordinating the program. "But funding is due to end in December. SPC is committed to sustaining certain activities of this project and so it is hoped that the breeding program in Samoa will continue."

In fact, taro farmers in Samoa will expect nothing else given that Iosefa's work has not only seen the introduction of several new species of taro in the country, but it is also assisting greatly in getting what was once a major exporting commodity back on its feet.

Before the onslaught of the infectious disease in 1993, taro exports in Samoa peaked at S$9.5 million. The following year, this fell dramatically to a mere S$0.2 million, and other neighboring islands like Fiji quickly filled the vacuum as a leading exporter of the product. While AusAID has been funding the TaroGen program in Alafua, Iosefa said this type of research had begun much earlier, in 1996.

Since then, the breeding program, which included the germination of taro plants using tissue culture, had produced ten taro species that could replace Taro Niue, the local taro species that almost got wiped out by TLB. As a result of the disease, several exotic taro cultivars from Palau, the Federated States of Micronesia and the Philippines were reported to have tolerance to TLB.

"After two years of on-farm evaluation, we found out that Palau-10 is the most resistant to TLB and with the highest yield," Iosefa said. "Talo Fili (PSB-G2) from the Philippines has the best eating quality with other Palau cultivars and two of Federated States of Micronesia's cultivars (Pwetepwet and Toantal) are tolerant to TLB and with acceptable eating qualities."

Iosefa was choosing his words carefully. The word in Samoa is that many still preferred the taste of Taro Niue, lamenting that the new breeds are still far off the mark when it comes to real taro flavor.

"Our breeding program for TLB resistant varieties is a long term research exercise. It is still on-going and may take another three to five years before we find what the Samoan people are looking for." An option Iosefa and his team at Alafua would like to look at is to continue breeding, mixing Talo Niue with Palau-10, which is why it is imperative to ensure funding continues for TaroGen. In 2000 and again in 2001, TaroGen through Samoa's Ministry of Agriculture released six "improved lines" of taro.

"Farmers liked it," said Iosefa. "USP's taro improvement project also released several clones for farmers to test under their local environment and management."

One of the benefits of the breeding program is the improvement in the tissue bank for Alafua's Tissue Culture Unit. Anthony Palupi, manager of the unit, said his unit duplicated the SPC's collection, and is concentrating on improving the multiplication rate of taro suckers.

From a sucker, Palupi said his unit could extract tissue for at least 70 to 200 new suckers.

Space has become a problem for the tissue unit, and SPC provided funding for the provision of a new sterile kitchen and bigger storage. The devastation caused by taro blight in Samoa had raised the need for island countries to observe strict quarantine regulations and move away from intensive monoculture.

"There shouldn't be a reliance on one variety for the domestic and export markets," said Iosefa.

There's also the need for genetic diversity in the region so breeding programs should be continued. We also should not just use Pacific germplasm. Exotic germplasm including those from Asia should be introduced. Genetic diversity in the Pacific is relatively limited. Because of this need for diversity, another major lesson learnt is we have to have germplasm exchanges between the countries and from outside the region. "But this germplasm exchanges should respect the quarantine regulations of the countries."

Posted 10:33 PM by Luigi
Current Status of PGR Activities in PNG

Last week I was in Rarotonga, Cook Islands, for a very interesting national PGR stakeholder consultation. I'll post some thing on this soon. This week, we're hosting Ms Rosa Kambuou of NARI, PNG, the national focal point for PGR issues. She's visiting us at SPC in connection with an FAO project on monitoring the Global Plan of Action for PGF for Food and Agriculture, and has given us the following summary of the current state of PGR activities in PNG.

Germplasm field collections

The national germplasm collections of banana (298 accessions), yam (31 accessions), cassava (87 accessions) and aibika (Abelmoschus manihot – 81 accessions) are maintained at DLP Laloki. The yam, cassava and aibika collections have been fully characterized and preliminarily evaluated. The banana collection is missing information on flower and fruit descriptors. This is an on-going problem where banana male buds are cut off and fruits are harvested before data is collected. Other NARI Programmes are maintaining only the working collections of these crops.

The national taro germplasm collection (>300 accessions) is maintained at NARI Bubia, outside Lae. This collection has been fully characterized, preliminarily evaluated and documented. A duplicate collection (20%) of the national taro collection is maintained at the Vudal University in PNG and the SPC Regional Germplasm Centre (RGC) in Fiji. The South Pacific Yam Network collection of yams is also maintained at Bubia and has over 300 accessions. This collection has not been fully characterized nor evaluated.

The national sweet potato germplasm collections are maintained at two locations: the lowland collection (>900 accessions) at NARI Keravat outside Rabaul and the highlands collection (>1,000 accessions) at NARI Aiyura.

A small collection of some exotic fruits and nuts species and traditional vegetables from PNG and other countries are maintained at Keravat. This collection has not been characterized nor evaluated.

Utilization

The materials from the national taro collection at Bubia are being used for a crop improvement programme. Some selections are being done for tolerance to pests and diseases and eating quality. For other crop collections, utilization of the germplasm is currently focused on selection of high yielding, good eating quality and tolerance or resistance to biotic and abiotic factors. Part of utilization is to multiply sufficient planting materials for dissemination to farmers. Selection for drought tolerant and good yielding cultivars of banana, sweet potato and cassava have greatly enhanced farmers production in the dry lowland areas of the country.

Documentation

The information and data on PGR collections are being maintained in Excel spreadsheet files. The NARI PGR section at Laloki is currently working on documenting cassava and aibika information into NARI publications. The section has also been working on producing five Minimum Descriptor Lists for banana, sweet potato, cassava, yam and aibika, based on the full IPGRI Descriptor Lists on these crops and other relevant publications. These Minimum Descriptor Lists are developed to assist the field officers in characterizing and evaluating field collections, and could be of use throughout the Pacific region.

National PGR Committee

PNG had its first National PGR Stakeholders meeting in November last year, with support from PAPGREN. Over 30 PGR stakeholder representatives attended. The participants had the opportunity to give a brief status report on their PGR programmes and contributed to group discussions which developed specific recommendations for action on priority crops. A highlight of the meeting was the formation of a national PGR coordination committee and the identification of its roles and functions. This committee is officially known as the PNG National Technical Committee on Plant Genetic Resources for Food and Agriculture (PNG/NTC/PGRFA). NARI was asked to provide the Chairmanship and the Secretariat for the Committee, while the Deputy Chair went to COGENT PNG (CCRI). All stakeholders present at the first meeting were invited to be members of the PNG/NTC/PGRFA.

Collaboration with Regional and International PGR Organisations

PNG collaborates with many regional and international organizations on matters relating to PGRFA, including SPC (RGC, TaroGen and PAPGREN), the Regional Biosafety Committee, INIBAP/BAPNET, PROSEA, the Regional Committee for South East Asia – PGR (RECSEA), the South Pacific Yam Network (SPYN), TANSAO, FAO, IPGRI, CBD and others.

There are also bi-lateral collaborations with individual countries. Recently, NARI has signed a Memorandum of Agreement with the Japanese National Agro Biotechnology Institute relating to collecting of wild relatives of rice, Vigna and sago.