Agribusiness Review - Vol. 6 - 1998

Paper 5
ISSN 1442-6951

The Demand for Seed Potatoes in South East Asia.

Peter J. Batt
Senior Lecturer, Horticulture,
Curtin University of Technology, Perth

• Introduction
• The Potato Industry In Asia.
• Seed Potatoes In Asia.
• Seed Potato Exports To Asia.
• Factors Influencing The Demand For Seed Potatoes.
• Conclusion.
• References.

Introduction

Over the last five years, it is apparent that the potential to export Australian seed potatoes to markets in South East Asia has received considerable attention from both Government and the private sector. No fewer than four DPIE Agribusiness Programs have been dedicated to expanding the market and improving the performance of Australian seed potato exports. A recent seed potato industry workshop sponsored by the HRDC (1996) , has established research and development priorities for both the domestic and export industry, with several research projects already underway to address some of the impediments raised.

In the private sector, a network of seed potato growers from Riana, Crookwell, Ballarat and Thorpdale have entered into a cooperative research program to evaluate the performance of 13 varieties of Australian seed potatoes in four locations in West and Central Java (Higginbottom, 1996) . In WA, a cooperative project between Western Potatoes, Curtin University, the International Potato Centre (CIP) and the National Potato Programs in Vietnam and the Philippines seeks to investigate opportunities for cultivating tropical potatoes in WA and the subsequent re-export of seed to South East Asia (Batt,1994a) . Dowling (1995) , reports on the progress Technico are making towards developing the market for in-vitro produced micro-tubers.

While few people doubt the long term potential of the market, there is some speculation as to just how big the market in South East Asia is for Australian seed potatoes. Estimates of the potential demand range from 120,000 tonnes (van der Zaag, 1986) to 150,000 tonnes per annum (Schmiediche, 1995) . However, in all probability, there will be a significant difference between the potential seed demand and the effective seed demand (Crissman, 1989) .

While this paper will attempt to quantify the size of the market for seed potatoes in South East Asia and to identify some of the factors which may influence the demand for Australian seed potatoes, it does not consider the various marketing strategies which may be employed by exporting firms to significantly influence the rate of adoption or the demand for seed potatoes in the market.

The Potato Industry In Asia.

Potato production in Asia is expanding. Over the last three decades, potato production in Asia has tripled to exceed 60 million tonnes (Vrolijk, 1994) . China is probably now the worlds' largest potato producer, although in the absence of reliable statistics, estimates of total production range from 30 million tonnes (van der Zaag, 1992) to 34 million tonnes (Vrolijk, 1994) .

The potato readily fits into the cereal based cropping systems found throughout Asia (Scott, 1994) . The introduction of improved, short duration varieties of wheat and rice has provided a niche for the potato crop in the agricultural production calendar, but unlike cereals, the potato crop does not need to grow to full maturity before harvest (Villamayor, 1984) .

Irrigation makes it possible to grow potatoes in hot, dry areas (Villamayor, 1984 and Scott, 1994 ); an abundant supply of cheap labour offers considerable opportunities for increased rural employment; and, the introduction of improved and better adapted varieties, chemical fertilisers, fungicides and pesticides, has significantly improved productivity per unit area ( Scott, 1994 and Schmiediche, 1995 ).

However, the major reason for the expansion in potato production has been the desire by farmers to satisfy expanding markets and changing consumer preferences. Population growth and urbanisation has expanded the market for food crops and rising per capita income has stimulated the demand for more exotic foods to diversify diets (Horton, 1987) . No doubt, one of the most significant factors driving the increase in potato consumption in Asia is the growth of the fast food franchises (Perez, 1995) . With increasing prosperity, there will be an increase in the consumption of processed potato products ( van der Zaag, 1990 ; Scott, 1994 ) and a corresponding shift from a staple food to a snack food ( van der Zaag, 1992 ).

Over the last three decades, the productivity of potato production in Asia has increased from an average of 5.85 tonnes per hectare (1961) to 13.29 tonnes per hectare (1991)( van der Zaag, 1992 ). The two most developed countries in Asia, Japan and South Korea, have experienced the most significant increases in productivity. However, the average yield in Asia remains low, for by contrast, the average productivity of potato crops in Australia is 29 tonnes per hectare (Batt, 1994b) .

While there is no reason to suppose that increases in productivity will not continue to improve, it is most unlikely that potato growers in Asia can ever achieve the levels of production which are attained in the temperate zones, due to the shorter growing season and higher temperatures reducing photo-synthetic efficiency (Horton, 1987) . The technical level of production in Asia, therefore, is not as poor as often assumed on the basis of productivity per hectare (Beukema and van der Zaag, 1990) . However, the majority of authors acknowledge that the major constraint to potato production in Asia is the inadequate supply of reasonably priced, good quality seed potatoes of the desired varieties ( Horton, 1987 ; Crissman, 1987 ; van der Zaag, 1987; van der Zaag, 1990; van der Zaag, 1992 ; Rasco and Aromin, 1994; Rasco, 1994 ; Vrolijk, 1994 ; and Schmiediche, 1995 ).  

Seed Potatoes In Asia.

No aspect of growing potatoes is more important than the selection of the best possible planting material, for the yield obtained from different stocks of the same variety under the same conditions of culture, depends more upon the quality of the planting stock than on any other single factor (Balaoing and Lazo, 1967) . Moreover, the use of high quality seed improves the productivity of traditional inputs such as labour, irrigation and cultivation practices (Monares, 1981) .

For economic and technical reasons, most seed potatoes produced in Asia are derived from imported seed, which is usually multiplied in-country one or more times (Beukema and van der Zaag, 1990) . However, imports are expensive, and there are additional problems associated with; the untimely arrival of the seed tubers, resulting in delayed planting and disruptions to cropping schedules; imports are only available for part of the year, which may not necessarily coincide with the most desirable planting times; and, tubers may not be of the desired physiological age for planting (Balaoing and Lazo, 1967) .

While many temperate varieties grow and yield well in the tropical highlands (Horton, 1987) , most have been bred and selected under very specific environmental conditions  (Beukema and van der Zaag, 1990) . When these varieties are cultivated under different agro-ecological conditions, many react adversely to the environment and only a few characteristics remain the same. Furthermore, there is always the risk of importing serious plant diseases. The recent discovery of Psuedomonas solanacearum Race III in the tropics suggests that the pathogen has been introduced through contaminated seed material (Schmiediche, 1995) .

Because of the difficulties experienced with imports, several countries in Asia have developed their own breeding and selection programs and with the recent advances in in-vitro propagation, many have developed their own programs to produce pre-basic seed. However, there are currently few successful seed programs operating in Asia (Schmiediche, 1995) . The fundamental problem appears to be that with the high rate of degeneration, seed deteriorates after only a few multiplications and thus, by the time the "improved" seed reaches the ware grower, it is already seriously contaminated by tuber borne diseases and virus.

In the tropics, the rate of seed degeneration is more rapid than it is in the temperate zones, for insect populations are higher, there are more potential sources of infection and seed storage is more difficult (Beukema, 1990) . However, a range of institutional and organisational impediments have also impaired the ability of national seed programs to significantly improve seed quality ( Monares, 1981 ; Crissman, 1987 ; Beukema, 1990 ). Poor management, poor coordination and cooperation between government departments, inadequate finance and logistical problems, have also contributed to the failure of formal seed programs to supply more than 5% of the annual seed requirements in Asia; compared with 85% in North America and 70% in Europe (van der Zaag, 1991) .

Thus the majority of seed used in Asia is sought from the informal seed system. The informal seed system consists of all farmer-based activities concerning seed production, distribution and utilisation ( Crissman, 1990 ). In an informal system, the farmer either produces his own seed or gets it from other farmers ( Beukema, 1990 ). However, where seed crops are harvested from ware crops, the risk of infection is high unless growers have taken the time to select those plants that are true-to-type, vigorous and healthy, or, to remove those plants which show symptoms of disease ( Kloos and van der Zaag, 1988 ; Beukema and van der Zaag, 1991 ).

Seed Potato Exports To Asia.

Asia is currently the fastest growing region for international trade in potatoes (Vrolijk, 1994) . The two sectors most likely to benefit from the expansion are processed potato products and seed.

The USA is the world's largest exporter of processed potato products (290,000 tonnes). Some 75% of USA exports were shipped to Asia, of which almost 75% were consigned to Japan. While exports of processed potatoes from both Canada and the Netherlands are increasing, the USA is expected to further consolidate its position as the major supplier of processed potato products to Asia ( Vrolijk, 1994 ).

Over the last two decades, the world market for seed potatoes has increased from about 800,000 tonnes per annum to exceed 1,100,000 tonnes per annum ( Lamont, 1993 ). The Dutch are the world leaders, with annual seed potato exports exceeding 500,000 tonnes (47%) ( Renia, 1992 ). Europe has traditionally been the major market for Dutch seed potato exports, but more recently, exports to Europe have declined from 79% to 61%, while exports to Asia have increased from 5% to 7%.

According to the ABS (1997), Australia exported over 2,800 tonnes of seed potatoes in 1996/97, worth over $1.44 million. The majority of exports (88%) were to markets in Asia. South Korea (44%), Thailand (23%) and Indonesia (12%) were the most important export markets for Australian seed potatoes in terms of volume (tonnes).

Despite the significant expansion in the area of potatoes cultivated in Asia, the importation of seed potatoes remains small. There is evidence to suggest that as the planted area increases, many Asian countries tend to rely more on domestic seed sources ( Vrolijk, 1994 ).

The low gross domestic product and where applicable, high import tariffs, often make imported seed too expensive for the majority of farmers, for seed costs account for between 30-50% of the costs of production ( Renia, 1992 ). The prices charged for imported seed may be 2.3 to 17 times higher than the cost of local seed, depending on the level of disease infection and the price the importer is willing to pay. However, even where importers may want to purchase imported seed, they may be prevented from doing so because of quantitative import restrictions, supply monopolies, or strict phytosanitary requirements.

Factors Influencing The Demand For Seed Potatoes.

The demand for seed potatoes will be influenced by the demand for fresh potatoes ( Crissman and Hibon, 1996 ). In turn, the demand for fresh potatoes will be influenced by the growth in population and rising per capita income ( Horton, 1987 ; Vrolijk, 1994 ).

However, seed potatoes are production inputs and therefore they are seldom considered as consumption goods ( Vrolijk, 1994 ), but in some parts of South East Asia, due to the importance of the informal seed system and the degree to which farmers select and retain their own seed, seed potatoes may have a dual role as both a consumer good and a production input ( Crissman and Hibon, 1996 ).

Because of overlapping production cycles or proximity to other production zones with different production cycles, the two markets are often physically and/or temporally intermixed. The seasonality of production, storage constraints and isolation from other production areas, may adversely affect the availability of seed.

As the planting season approaches, potatoes that have been classified by size in the ware market may be re-classified as seed; a production input. Small seed sized tubers can therefore change definition and change markets.

In estimating the size of the seed potato market in Asia, many have calculated the annual seed requirements by multiplying the number of hectares planted by the seed rate per hectare ( van der Zaag, 1986 ; Crissman, 1989 ; Schmiediche, 1995 ).

Crissman, 1989 and Della Vedova and Brieva (1995) provide a model, with major limitations, to estimate the annual seed requirements, where;

TSDj = Aj x Sj x Rj

Where TSDj is the total seed demand for variety j (tonnes)

Aj is the area (hectares) planted in variety j

Sj is the seed rate (tonnes per ha) for variety j

Rj is the seed renewal rate for variety j

Although very simplistic, even performing a calculation of this magnitude may prove difficult in Asia. Accurate statistics of the total area planted in potatoes are seldom available because of the large numbers of smallholders who generally cultivate small areas of potatoes within a diverse mixed cropping enterprise system. The problem is further compounded where the farmers may own a number of small parcels of land, often in different locations ( Crissman, 1989 ).

Many assume that the seed rate in Asia is similar to that used in the temperate zones (1.8-2.5 tonnes per ha or 40,000 stems per ha), but there is evidence to suggest that such is not entirely appropriate, for the seed rates used in Asia are often much lower than those used in the temperate zones because of the scarcity of seed and the high cost of seed ( Monares, 1981 ; Crissman, 1989 ).

Because of the scarcity of seed and the desire to extend the high cost of seed as far as possible, the cutting of seed tubers is often practised. Francisco (1987)(cited in Crissman, 1989 ), suggests that as many as two-thirds of the potato farmers in the Philippines use cut seed. By using cut seed, potato farmers in Chiang Mai (Thailand), have been able to reduce the seed requirement to only 0.4-0.6 tonnes per hectare ( Rasco and Aromin, 1994 ). However, if soil conditions are unfavourable and if the seed is physiologically old, seed cutting is not advisable ( Beukema and van der Zaag, 1986 ).

The seed rate used in the tropics may also be influenced by agronomic factors. In the tropical lowlands, the ideal seed rates may be 29-50% more than comparable seed rates used in the highlands ( Monares, 1981 ; Villamayor, 1984 ). However, the seed rates actually used may be much lower because of the lack of adequate quantities of good quality seed at planting time ( Aromin et al, 1993 ; Callueng et al, 1993 ).

Seed size will also influence the seed rate per hectare. If large seed is used, a greater weight of seed must be planted ( Beukema and van der Zaag, 1990 ). However, depending on the purpose for which the crop is intended, different seed rates may be required. Where the crop should contain a high percentage of large tubers, such as for the ware market or processing, the seed rate should be lowered, whereas, if the objective is to produce a greater proportion of small tubers (seed), the planting density should be increased. However, the economically optimum plant density will be influenced by the price of the seed and the price the farmer receives for his ware potatoes.

When tuber size is the major variable used for selecting planting material, prices in the ware market will determine how much seed the farmer will retain ( Crissman and Hibon, 1996 ). Normally, the farmer will keep the smaller tubers for seed, but there is a switching price above which the farmer may decide to sell all of the crop to the ware market and to acquire seed off the farm at a later date. The decision will be influenced by the seed storage facilities the farmer has at his disposal and the anticipated losses during storage ( Beukema and van der Zaag, 1990 ; Beukema, 1990 ; Della Vedova and Brieva, 1995 ).

Seed is the most expensive input for producing potatoes in Asia ( Horton, 1987 ; Crissman, 1989 ; Rasco and Aromin, 1994 ; Vrolijk, 1994; Crissman and Hibon, 1996 ). The cost required to plant one hectare of potatoes is ten times the cost of planting a wheat crop and almost sixty times the cost of establishing a rice crop (Huda, 1990 ). Seed is expensive, even if it is not purchased, for farmers have the option of selling the tubers to the ware market or eating the tubers themselves ( Monares, 1981 ).

In Asia, few farmers have the capital resources to be able to outlay the funds required to purchase substantial quantities of seed. Thus the availability of finance and the cost of finance will influence the demand for seed ( Crissman, 1989 ; Beukema, 1990 ; Beukema and van der Zaag, 1990 ; Della Vedova and Brieva, 1995 ).

The effective seed demand (ESDj) emphasises the difference between the farmers desire to purchase seed and their ability to do so. While this is exceedingly complex, given the multiple number of factors influencing the farmers decision to purchase a particular variety, Crissman, 1989 , has sought to simplify the equation by multiplying the total seed demand (TSDj) by the proportion of seed sourced from the informal seed sector (ISSj)(which includes the seed retained by the farmer) and to subtract that from the total seed demand;

ESDj = TSDj - (TSDj x ISSj)

Where ESDj is the effective seed demand for variety j (tonnes)

ISSj is the proportion of seed of variety j sourced from the informal seed market.

Where the farmer is a member of a Government approved seed scheme ( Crissman, 1989 ), or a cooperative farmer group, low interest loans are often available to purchase seed ( Batugal et al, 1988 ; Crissman and Hibon, 1996 ). Where the farmer is cultivating the crop under contract for a processing company, the seed and other inputs may be supplied ( Crissman, 1989 ). In other instances, farmers are forced to make private arrangements with wholesalers and traders to loan the seed and to repay the loan at harvest ( Crissman 1987 ; Crissman, 1989 ; Beukema, 1990 ).

In a well developed market, where production is relatively stable and the supply is fairly predictable, ware prices seldom vary in real terms. In this instance, there is a high rate of improved seed use. However, in regions where the market price of potatoes fluctuate and yields are unpredictable, the demand for improved potato seed will be lower ( Beukema, and van der Zaag, 1990 ).

A farmers decision to purchase improved seed is made knowing that the benefits will be realised over several seasons. However, the benefits arising from the increased yields will decline progressively as the seed degenerates ( Crissman and Hibon, 1996 ). How often farmers renew their seed depends on the rate of degeneration ( Monares, 1981 ; van der Zaag, 1986 ; Beukema, and van der Zaag, 1990 ; Beukema, 1990 ; Della Vedova and Brieva, 1995 ).

The rate of degeneration depends on the initial quality of the seed, the agro-ecological conditions, the variety ( Monares, 1981 ); and the measures the farmer takes to control the spread of disease including crop rotation, planting time, harvest date, positive plant selection, roguing and chemical spraying; harvesting procedures; storage methods and tuber sorting and grading methods ( Beukema, 1990 ).

The rate of seed degeneration will determine the number of times the farmer can profitably use his own seed ( Beukema, 1990 ). The lower the rate of tuber infection and the higher the potential yield, the more times the seed can be profitably used before the yield declines. Potato farmers in the lowlands are more likely to renew their seed more frequently because the yield difference between imported seed and the seed harvested from the previous crop is much greater ( Monares, 1981 ).

Conversely, because the rate of seed degeneration is lower in the highlands, farmers are more likely to retain their seed for a longer period. However, with each successive harvest, the proportion of the crop that must be retained for seed increases as the productivity of the seed decreases ( Haverkort, 1986 ).

The productivity of the seed is dependent on the level of technology adopted by the farmer. While many authors acknowledge that the lack of seed is the major constraint to potato production in Asia, the productivity of the crop is also highly dependent on soil fertility ( Haverkort, 1986 ; and Rasco and Aromin, 1994 ); the availability and frequency of irrigation ( Crissman, 1989 ; Rasco and Aromin, 1994 ; Scott, 1994 ; Vrolijk, 1994 ); the application of chemical fertilisers ( Crissman, 1989 ; Scott, 1994 ; Vrolijk, 1994 ); pest and disease control ( Haverkort, 1986 ; Crissman, 1989 ; and Beukema, 1990 ); and, the suitability of the variety ( Haverkort, 1986 ; van der Zaag, 1990 ; Scott, 1994 ; Vrolijk, 1994 ; Della Vedova and Brieva, 1995 ).

Where the yields are low, it is more difficult to justify the use of high quality seed ( van der Zaag, 1987 ). In much of Asia, it is often more profitable for the farmer to use poorer quality seed ( Beukema, 1990 ).

The variety a farmer grows often reflects historical patterns of colonialisation and trade, as well as the production environment, the cropping system, food requirements and the consumers preferences ( Horton, 1987 ; van der Zaag, 1990 ). To yield well in the tropics, a variety must be able to cope with the higher temperatures, higher humidity, a shorter day length and a shorter growing period; higher levels of pests and diseases; and grow well with only minimal inputs ( Renia, 1992 ). The variety must also have a good storage capability and fit into the window of opportunity in the cropping season ( Horton, 1987 ).

In much of Asia, early maturing varieties are preferred, for it is possible to achieve a multiple number of crops per year and there is always the risk of yields being suppressed by unfavourable environmental conditions and pest and disease infection.

In choosing a suitable variety, farmers use a number of criteria including; (1) yield; (2) resistance to disease; (3) eating quality; and (4) desired tuber characteristics; (i) skin colour; (ii) flesh colour; (iii) tuber size; (iv) tuber shape and (v) storage ability ( Horton, 1987 ; Crissman, 1989 ; Callueng et al, 1993 ). Farmers seldom use a single criteria in selecting or rejecting a variety. Rather, the decision is made with consideration to a number of both positive and negative attributes ( Callueng et al, 1993 ).

Consumers often prefer a certain variety, therefore, it may be more profitable for the farmer to grow a well accepted, less productive variety because of the higher prices received ( Horton, 1987 ; van der Zaag, 1990 ). Potato processors particularly, often pay significant price premiums for favoured varieties ( van der Zaag, 1990 ). However, not all potatoes are suitable for table consumption and processing and thus the demand for a particular variety will reflect changing patterns of utilisation. Furthermore, the lack of seed often means that the farmer will be forced to plant whatever variety is available at that time ( Crissman, 1989 ).

Seasonal variations in the tropics can also influence the yield, market prices and the subsequent demand for seed. The demand for seed is dependent upon the monsoons ( Raghubanshi and Tewari, 1974 ). After planting, should the potato crop fail because of typhoons, the demand for seed the following year may be much higher, because farmers were unable to retain sufficient seed to re-plant ( Crissman, 1989 ).

Conclusion.

Allowing for the importance of the informal seed system and the farmers average rate of seed renewal, it is estimated that the demand for seed potatoes in South East Asia will approach 31,900 tonnes per annum. However, the effective seed demand will be much lower because quantitative restrictions and import quotas limit the entry of seed potatoes and because of the farmers inability to pay.

Nevertheless, the demand for good quality seed potatoes of the desired variety, physiological age and size is increasing in South East Asia. Although potatoes are not part of the traditional diet, as personal disposable income increases, the demand for potatoes and processed potato products (french fries and crisps) will increase.

Thus the major demand for seed potatoes in South East Asia will be for those varieties considered most suitable for processing. However, whereas the majority of potatoes are grown in the tropical highlands, as land pressures intensify and crop rotations become shorter, the incidence of pests and diseases are accumulating, increasing the costs of production and depressing yields. Consequently, there is a general move away from the traditional areas of production to the tropical lowlands. In this environment, the cropping season is very short and few of the existing processing varieties have proven to be suitable.

Fortuitously, for the desired planting time, the majority of seed crops in the northern hemisphere are physiologically immature and problems are frequently experienced with imported seeds emerging erratically.

In this respect, Australia's proximity to the market and the ability for Australia to supply seed potatoes out-of-season to seed producers in the northern hemisphere will place Australian seed producers in a strong position in the market.

However, Australia will face increasing competition for a share of the seed potato market in South East Asia. Greater quantities of seed from Europe and the USA are being consigned to the region. In order to compete, Australian seed producers will need to give greater consideration towards producing seed within the desired size range and producing seed of those varieties that are in demand.

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