Sweet Potato in Papua New Guinea by krs20830

VIEWS: 56 PAGES: 56

									  Sweet Potato in
 Papua New Guinea
               Mike Bourke
    Department of Human Geography
Research School of Pacific and Asian Studies
    The Australian National University
           Canberra ACT 0200
     Email: mike.bourke@anu.edu.au
Sweet Potato in Australia
1.    Where is sweet potato grown in Australia
2.    Volume of sweet potato produced or sold
3.    Production trends
4.    Number of sweet potato producers
5.    Main markets
6.    Price paid to growers and retail price (ranges)
7.    Main cultivars grown
8.    Most important production or marketing constraints
9.    How is soil fertility maintained?
10.   Environment of one producing area (rainfall, annual and
      seasonal distribution; temperature and temperature
      seasonality; soils; landform)
This presentation
 This presentation is about information and knowledge
 It’s about what we know or should know about aspects of
 sweet potato in PNG
 It is also about how to find out information in PNG
 There is specialist knowledge, for example, on viruses that
 only a few people might have
 There is also a knowledge or skills that some have and
 others do not, for example, networking or cultivar
 identification
 The information presented is that which we should all agree
 on
 It is basic information about sweet potato production and
 marketing in PNG
 It provides the basis for improving the quantity and quality
 of food produced and food sold within PNG
Sweet Potato in PNG: some short
questions
1.    Where is sweet potato grown in Papua New Guinea
2.    Volume of sweet potato produced each year
3.    Production trends over past 40-60 years
4.    Number of sweet potato producers in PNG
5.    Main destinations for marketed sweet potato
6.    Retain price in different centres
7.    Main cultivars grown
8.    Most important production or marketing constraints
9.    How is soil fertility maintained?
10.   Environment from one producing area (rainfall, total and
      seasonal distribution; temperature (including temperature
      seasonality) soils; landform)
Sweet Potato in Papua New Guinea
Relative significance of SP in PNG agricultural systems: 1990-95


 Production locations
Production volume in Papua New
Guinea
Production volume in Papua New
Guinea
Number of people growing sweet potato
 Sweet potato is the most important food
 (dominant staple) for 2.8 million rural people in
 PNG (65% of the rural population)
 As well, it is an important food (sub-dominant
 staple) for a further 700,000 people (17% of the
 rural population)
 Thus it is an important or the most important
 food for 3.5 million people or 82% of the rural
 population
 Most other rural people live in locations where
 some sweet potato is grown
Production trends for sweet potato
 Sweet potato was introduced into eastern
 New Guinea (mainland PNG) about 300
 years ago, coming from eastern Indonesia
 and moving from the Sepik Basin into the
 Central Highlands.
 It was introduced into the Islands Region
 of PNG after 1800 AD and generally after
 1870 AD.
 Sweet potato production has increased
 greatly in PNG over the past 65 years
 (since 1941)
Relative significance of SP in PNG agricultural systems, 1940
Relative significance of SP in PNG agricultural systems: 1990-95
Volume of sweet potato sold in PNG
each year
 No precise estimates are available
 It is crudely estimated that 25,000 to
 50,000 tonnes of sweet potato is sold in
 PNG each year
 The volume of sweet potato and other
 food crops has increased rapidly since
 1998
                                        Exchange rate, PNG kina vs US dollar, 1975–2003
                                        (Source: Bank of PNG)


                1.60

                1.40

                1.20
Exchange rate




                1.00

                0.80

                0.60

                0.40

                0.20

                0.00
                   1975   1977   1979     1981   1983    1985   1987   1989   1991   1993   1995   1997   1999   2001   2003
                                                                       Year
                                       Figure 5.1.1 PNG consumer price index, 1962–2005

                       800

                       700
CPI (base year 1977)




                       600

                       500

                       400

                       300

                       200

                       100

                         0
                         1960   1965    1970      1975     1980          1985   1990      1995   2000   2005
                                                                  Year
                           Figure 5.2.3 Average retail price of rice in Port Moresby and Madang, 1971–2005

                  300

                               Port Moresby
                               Madang
                  250


                  200
Price (toea/kg)




                  150


                  100



                   50


                    0
                    1970       1975           1980   1985          1990    1995       2000       2005
                                                            Year
                           Figure 5.2.1 Average market price of sweet potato in Port Moresby and Madang,
                           1971–2005

                  140

                             Port Moresby
                  120        Madang


                  100
Price (toea/kg)




                   80


                   60


                   40


                   20


                    0
                    1970      1975          1980    1985          1990    1995       2000      2005
                                                           Year
                              Rice imports per person and trends by decade, 1961-2003


                         50
                                                                                   1991-2000
                         45                                                        0.1%
                                                               1981-90
                                                               1.9%
                         40
kg per person per year




                         35                         1971-80
                                                    5.2%
                         30
                                                                                         2000-03
                         25               1961-70                                        -3.9%
                                          6.3%
                         20


                         15


                         10
                          1960     1965      1970   1975      1980   1985   1990      1995     2000
Main markets
 Numerous local markets (many hundreds
 in PNG)
 In all 40 urban locations (where
 population is more than 1000 people)
 Numerous markets in villages, roadside,
 government station, missions, logging
 camps etc
 Long distance trade in sweet potato from
 Eastern Highlands and Western Highlands
 to Lae, Madang and Moresby
Demand for sweet potato in urban
locations
 There exists a strong demand for sweet potato in both rural
 and urban households
 A study of demand for different types of food in rural and
 urban PNG was done by John Gibson
 ‘There was a rise in the quantity of sweet potato consumed
 as household income rose’
 ‘A 10% increase in household income causes a 7% increase
 in the quantity of sweet potato consumed in the rural
 sector’
 ‘A rural household with K100 to spend would allocate K8.74
 to extra sweet potato consumption, so future research
 payoff is likely to be greatest from sweet potato’
 Source: J. Gibson (2001)
Retail price
 Varies greatly between locations.
 Most expensive in Port Moresby; least expensive in remote
 rural locations
 Price of sweet potato in Port Moresby is typically two to
 three times the price of the other main towns (Goroka, Lae,
 Madang, Rabaul)
 Information on price is collected for the CPI and available
 from National Statistical Office
 Price in Port Moresby in 2005 was about K1.30 per kg
 (Equivalent to about K3.90 in rice equivalent terms)
 Price in Madang in 2005 was about K0.60 per kg
 (Equivalent to about K1.80 in rice equivalent terms)
Cultivars
 Unknown number used in PNG
 Crudely estimated that about 5000
 cultivars are grown in PNG
 No single cultivar dominates production or
 trade
 Big range in flesh and tuber skin colour
 Lower moisture content types strongly
 preferred
Main production constraints
 Improved planting material (limited number of
 improved cultivars available)
 Soil fertility maintenance
 Diseases, especially post-harvest and viruses
 Nematodes?
 Pests. Weevil, but only in some locations or in big
 drought years
 Climatic extremes, particularly excessively high
 soil moisture and frost
 Marketing chains issues
Main research on sweet potato in PNG
over the past 20 years
 A summary of previous research was
 published in the PNG Agricultural Journal
 by Bourke (1985)
 A significant amount of research has been
 conducted and published since then
Main research on sweet potato in PNG
over the past 20 years
 Comprehensive evaluation of 1167
 cultivars (P. Van Wijmeersch 2001)
 On-going evaluation of some of these
 recommended cultivars
 Detailed description of agricultural
 systems (R.M. Bourke et al 1998)
 Assessment of the suitability of
 agricultural land for suitability of sweet
 potato (L. Hanson et al 2001)
Suitability of agricultural land for sweet potato
production in Bougainville
Main research on sweet potato in PNG
over the past 20 years (continued)
 A series of studies on aspects of agronomic and crop
 physiology
 Identification of major and minor disease problems (P.
 Kokoka 2001)
 Identification of the causes of variation in supply of tubers
 over time (R.M. Bourke 1998)
 Description of commercialisation of the crop in the
 highlands (K. Benadiktsson 2002)
 The method of transfer from the crop’s South American
 homeland into Oceania (E.g. M. Allen 2005; P. Weissner
 2005)
 The rate of adoption in the Western Pacific and the impact
 on local food production systems (C. Ballard et al Eds 2005)
Future Research needs for Sweet Potato
in PNG (from 2004 Aiyura workshop)
 Main research issues include:
   Assessment of yield losses caused by pests
   and diseases.
   Agronomic evaluation of cultivars under
   highland conditions.
   Post-harvest handling and quality control
   problems.
   A review of past published and unpublished
   research on the crop in PNG.
Future Research needs for Sweet Potato
 Main research issues in PNG cont’d:
   The causes of apparent yield decline over time
   for some cultivars.
   The influence of soil moisture extremes on
   crop growth and yield; and of soil moisture by
   nitrogen interactions.
   Management of cultivars by villagers, including
   cultivar replacement.
   Soil fertility management by villagers.
Sources of information
 There is a huge literature on the environment
 and agriculture in PNG
 There is better data on many aspects of PNG
 than in most other developing countries
 Some is out of date with changing social and
 economic situation (for example levels of cash
 income), but much is still valid
 An example is the book Climate of Papua New
 Guinea by John McAlpine and Gael Keig (with Rex
 Falls)
 Copies of this book are available
Literature databases
 There are four databases on literature on PNG
 agriculture, each with different strengths and
 weaknesses
 Robin Hide, Canberra
   Private bibliography
   Ca 19,000 entries
   Contains much recent international literature
 PNG Agriculture Literature Database
   Developed by Land Management Group, ANU
   Ca 15,000 entries
   Entries have less errors than first or third databases
Literature databases (continued)
 PNG National Agricultural Information
 System
   Built from early version of PNG Agricultural
   Literature database, contents of NARI, OPRA,
   Ramu Sugar library contents
   Ca 30,000 entries
 People in New Guinea (Terry Hays)
 database
   Focus on people; island of New Guinea
   Ca 10,000 entries
   Entries have minimal errors
Some examples of the type of data held
in spatial databases
                                      Daily maximum temperature
                                                               Kavieng
                                                 Daily Maximum Temperature
                                                                                                                                                                         Temperature change, Kavieng 1973-1999
                             1.0


                             0.8


                             0.6
Temperature Anomaly (degC)




                             0.4


                             0.2                                                                                                                                      Deviation from
                                                                                                                                                                      average daily
                                                                                                                                                                      maximum
                             0.0                                                                                                                                      temperature
                                                                                                                                                                      5 year running
                                                                                                                                                                      mean

                             -0.2


                             -0.4
                                                                                                                                                                  Kavieng

                             -0.6
                                                                                            1.0
                                                                                                                                                                Mean daily temperature
                                                                                                                                                           Mean Daily Temperature



                             -0.8                                                           0.8
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                                                        Year
                                                               Temperature Anomaly (degC)




                                                                                            0.4


                                                                                            0.2
                                                                                                                                                                                                                                                                  Deviation from
                                                                                                                                                                                                                                                                  average daily
                                                                                            0.0                                                                                                                                                                   temperature
                                                                                                                                                                                                                                                                  5 year running
                                                                                                                                                                                                                                                                  mean
                                                                                            -0.2

                                                                                                                                                                                                                                                                                          Kavieng
                                                                                            -0.4
                                                                                                                                                                                                                                                                   Daily minimum temperature
                                                                                                                                                                                                                                                                         Daily Minimum Temperature
                                                                                                                                                                                                                                   1.0
                                                                                            -0.6


                                                                                            -0.8                                                                                                                                   0.8
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                                                                                                                                                                                                                                   0.6
                                                                                                                                                                    Year
                                                                                                                                                                                                     Temperature Anomaly (degC)
                                                                                                                                                                                                                                   0.4


                                                                                                                                                                                                                                   0.2                                                               Deviation from
                                                                                                                                                                                                                                                                                                     average daily
                                                                                                                                                                                                                                                                                                     minimum
                                                                                                                                                                                                                                   0.0                                                               temperature
                                                                                                                                                                                                                                                                                                     5 year running
                                                                                                                                                                                                                                                                                                     mean




                                    Global climatic change
                                                                                                                                                                                                                                  -0.2


                                                                                                                                                                                                                                  -0.4


                                                                                                                                                                                                                                  -0.6


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                                     Figure 1.10.5 Land area used for agriculture by altitude class and province

                                  18,000
Land used for agriculture (km )
2




                                  16,000                                                                                 Altitude class
                                  14,000
                                                                                                                           2400–2800
                                  12,000
                                                                                                                           1800–2400
                                  10,000
                                                                                                                           1200–1800
                                   8,000
                                                                                                                           600–1200
                                   6,000
                                   4,000                                                                                   0–600
                                   2,000
                                       0
                                                      l
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Figure 1.10.6 Total population by altitude class (100/200 m bands)


                       Figure 1.10. 7 Total population by altitude class, 2000

             1800000

             1600000

             1400000

             1200000
Population




             1000000
                                                                                                                                                                                                Series1
             800000

             600000

             400000

             200000

                  0
                                 100-200
                                           200-400
                                                     400-600
                                                               600-800
                                                                         800-1000
                         0-100




                                                                                    1000-1200
                                                                                                1200-1400
                                                                                                            1400-1600
                                                                                                                        1600-1800
                                                                                                                                    1800-2000
                                                                                                                                                2000-2200
                                                                                                                                                            2200-2400
                                                                                                                                                                        2400-2600
                                                                                                                                                                                    2600-2800
                                                                                         Altitude
Soil fertility maintenance
Trees planted in fallow vegetation
Rotation of food legumes and sweet potato
Spatial databases
 PNG Resource Information System (PNGRIS)
   Developed by CSIRO (with DPI staff inputs)
   Based on detailed land use mapping done by CSIRO from mid-
   1950s to early 1970s, other data and extrapolation
   Huge amount of information on physical landscape of PNG, as
   well as land use
   Almost all data is still valid
 Mapping Agricultural Systems in PNG project (MASP)
   Initially developed by a DPI staff member and fully developed
   by group at ANU (working with staff from DAL, UPNG, Dept
   Forestry and NRI)
   Designed to complement PNGRIS database
   Detailed mapping of 342 ‘agricultural systems’, with
   information on over 100 parameters
   Fieldwork conducted mostly in 1990-1995 (Bougainville done
   in 2002)
   Some information is out-of-date, but most is still valid
Spatial databases (continued)
 These databases are held by NARI, DAL, DNP and
 other PNG government departments
 Many Papua New Guineans have been trained in
 their use at a general level (over 100 people) and
 at an advanced level (dozens).
 Only a few people (2?) in PNG use them on a
 regular basis
 Consultants do use them from time to time
 Analysis of databases has been supported by
 ACIAR and AusAID
 One output is the Papua New Guinea Rural
 Development Handbook
 Further information:P. Vovola and B.J. Allen
 (2001)
Concluding remarks
 Sweet potato is widely grown in PNG
 It is by far the most important crop in the country
 Production has increased greatly over the past 65 years,
 and especially since the devaluation of the PNG currency in
 1997
 A high proportion (over 80%)of the rural population grow it
 as a minor or major staple food crop
 It is less important in lowland locations where land is
 subject to inundation
 A significant, but unknown amount is sold in PNG each year
 (probably more than is sold in Australia each year)
 Consumers have a high preference for sweet potato,
 provided that the price and quality is acceptable
Concluding remarks (continued)
 There are a number of constraints to production and marketing
 These include: lack of availability of superior cultivars; inadequate
 soil fertility maintenance; diseases, especially post-harvest rots
 and viruses; occasionally weevil; environmental extremes,
 especially excessive rainfall and frost; poorly developed marketing
 chains.
 The constraints have been identified in broad terms, but much
 more detailed research and development is needed to reduce their
 impact and to improve production and marketing of sweet potato
 There is a significant amount of information known about sweet
 potato in PNG
 There is a very large amount of available information on people
 and the environment in PNG
 That information should be used to design and to conduct
 agricultural research in PNG

								
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