Agribusiness Review - Vol. 3 - 1995

Paper 3
ISSN 1442-6951

Developing advanced seed potato technology¹ :
The case of Technico Pty Ltd

Ben Dowling ²
1 - Patent applied for.
2 - Technical Manager, Technico Pty Limited

• Abstract
• Seed Potato Production
  • Table 1: Cost Per Tonne And Corresponding Unit Cost Of Seed Potatoes
• Establishing A Modern Seed Scheme
  • Figure 1: Steps Involved In Conventional Tissue Culture Based Programs
• Development Of The Process
• Potato Technitubers
• Utilising Technitubers
• Initial Commercial Developments
• Future Seed Potato Possibilities

Abstract

Examined in this article are the issues affecting the development of advanced seed potato technology. Potatoes are the world's fourth largest crop after wheat, rice and maize with annual production valued at US$1 Go billion. The potato is a staple food commodity in many countries, providing valuable nutritional benefits. Processed potato products, such as chips and crisps, are widely used as 'fast food' and snack foods', respectively.

The potato is prone to more than one hundred diseases caused either by bacteria, fungi, viruses or microplasmas. Since potatoes are usually grown from tubers rather than botanical seed, the seed tuber often provides the major source of disease infection. Therefore, the disease status of a crop often reflects the spectrum of diseases carried by the seed tubers to produce it.

The seed potato industry is by far the world's largest seed industry in terms of value and volume of seed produced annually. There is a worldwide shortage of quality seed potatoes, leading to reduced crop yields and poor tuber quality in many countries. The subsequent potato production limitations are hindering fresh and processed potato industry expansion in many countries.

It is estimated that only about 11 per cent of the world's potato crop is grown from clean, certified seed. Shortage of clean seed is particularly a problem in developing nations where production often occurs with degenerated seed, rather than with higher yielding quality seed. Some major producing countries such as Russia have no certified seed schemes at all.

Generally, the lack of supply of quality seed results in the small tubers from one year's crop being retained as seed for the next year's crop. This re-use of potato stocks as seed tubers contributes to a reduction in crop quality and yield, as well as the use of up to 25 per cent of the saleable production in order to ensure the following year's crop. The requirement for 2-3 tonnes of seed per hectare can cause seed costs to account for up to 60 per cent of total production costs in many countries.

Seed potato production

All modern seed potato certification schemes are based on a 'flow through' principle, whereby material of high health status enters the top end of the seed scheme, and after a limited number of field multiplications, certified seed passes out the 'bottom end' of the scheme.

Table 1 : Cost per tonne and corresponding unit cost of seed potatoes

Note. These costs are estimates only based on the New South Wales seed scheme, to illustrate the principle. Unit costs for G1 G4 seed are based on an average 100g tuber.

With developments in in-vitro culture of potato plantlets over the recent years, together with development in disease detection techniques, it has become possible to maintain disease free potato plantlets in culture. Pathogen tested plantlets growing under sterile conditions in the laboratory are of the highest health status, and form the 1 nucleus stock' for certified seed multiplication programs. The importance of disease free stock at the start of potato multiplication programs cannot be overstated.

In various seed schemes around the world, material leaving the laboratory enters the top end' of a seed scheme in one of the following ways:

• Minitubers: Plantlets are de-flasked into steam-pasteurised potting mix in insect proof screen houses and grown for 12-15 weeks to yield minitubers which, after breaking dormancy, may be planted in the field.

• Transplants: Plantlets are de-flasked into steam-pasteurised potting mix in seedling trays and hardened off in polyhouses for 2-3 weeks prior to planting in the field as transplants.

• Microtubers: Plantlets growing in-vitro are placed under tuber induction conditions to form microtubers whilst still in the flask, and breaking dormancy microtubers may be planted in the field.

Large numbers of propagules (most commonly, minitubers), are planted in the field each year in Australia, to produce the first field generation in the various State-certified seed schemes. A limited number of subsequent field generations (3 to 5) follows, in which perhaps seven tonnes of first field generation seed is multiplied up to produce up to 30000 tonnes of fifth generation seed.

By minimising the number of field generations, seed growers are able to:

• reduce seed exposure to field-borne diseases,
• reduce accumulation of tuber-borne diseases, and
• rapidly introduce new varieties.

The main limitation on reducing the number of field generations is that unit costs of the end product (certified seed) must be affordable to the commercial grower. The unit cost of transplants, minitubers and microtubers is very high - and the main way in which this cost is alleviated is through the successive multiplication of material (tubers) in the field. Each field multiplication reduces the unit cost of the seed tubers produced (see Table 1) but the risk of disease infection rises. Therefore a means of reducing the unit cost of the initial seed stock (the propagules leaving tissue culture based programs) is of immense importance to the potato industry.

Establishing a modern seed scheme

In New South Wales the seed scheme was reconstructed in the 1980s to gain the most advantage from tissue culture based programs. A limited generation seed scheme was introduced in 1983/84, when NSW Agriculture, a Government agency, assumed responsibility for seed potato certification in the State. This scheme, based on the tissue culture of pathogen-tested (pt) plantlets, was modelled on one already existing in Victoria. Tissue culture based programs work in the manner illustrated in Figure 1.

The scheme introduced by NSW Agriculture was based on production of minitubers in screen houses. Minitubers were then supplied to selected foundation seed growers in the Crookwell district. This arrangement continued for the next four years. This service was privatised in 1988 with the government's services being taken over by a private laboratory and the Crookwell Potato Association.

Figure 1: Steps involved in conventional tissue culture based programs

In September 1988, Grass Roots Limited at Paddy's River began in-vitro propagation of potato plantlets. Grass Roots Pty Limited sends flasks of in-vitro plantlets to an on-farm polyhouse facility at Crookwell. Here the plantlets were de-flasked for transplant or minituber production.

With only four field generations the NSW scheme was very short by world standards. This meant that the seed growers had very little room for absorbing the high cost of early generation planting material. Thus, the industry was keen to develop methods of reducing the costs of material leaving the laboratories and on-farm facilities. To this end, Grass Roots Pty Limited undertook a research and development project, based on the in-vitro production of microtubers. This project was funded by Grass Roots Pry Limited and the Crookwell Potato Association Inc., with matching funds from the Horticultural Research & Development Corporation. The aim of the project was to simultaneously develop a commercial method for mass-producing microtubers, and produce them at a low unit cost compared to minitubers.

Development of the process

During the term of this project, a variation on the in-vitro microtuber production system was discovered which was far more productive than the in-vitro microtuber system, as developed. This production system embraced a number of the features (concepts) developed during the in-vitro microtuber production project, but offered the following advantages:

• lower unit cost of propagules,
• highly productive for all varieties tested, and
• larger seed potato produced.

The outstanding productivity gain from this new process led Grass Roots Pry Ltd. and the Crookwell Potato Association Inc, to form a new horticultural technology company - Technico Pry Limited. Technico was formed primarily to commercially develop the new potato propagation technology. This technology enables the mass production, on a year-round basis of a unique potato propagule - a miniature seed potato known as a 'Technituber', now a registered tradename. By developing a method of mass producing Technitubers at a very low unit cost (compared to conventional minitubers), the company has the potential to dramatically change the worlds seed potato industry.

Technico has already started construction of a production facility in Australia, which will be commissioned in January 1996. In the first year of operation this facility will have the capacity to produce very large numbers of Technitubers for use both domestically and for export to various Asian countries. With the combination of very large-scale production of low cost Technitubers and higher field planting densities, production of affordable seed may now be possible from significantly reduced field multiplications.

Potato Technitubers

Technitubers are a unique potato propagule that can be produced on a year round basis at low unit cost. It is because of this combination of attributes that Technitubers offer a real opportunity for changing the pattern of seed potato production.

Technitubers are miniature seed potatoes, being approximately 1O-15mm in diameter, which makes them ideal for storage and for shipment interstate and overseas. Production of Technitubers occurs under controlled environmental conditions, thus allowing for full control of the potato plant's growth and development. This is very important to the process.

Having a factory-style production environment allows for the adoption of hygiene standards far above that which can be achieved in conventional seed production systems. The technology is being further enhanced through the development of a Quality Assurance program for the entire process. This will facilitate the issue of phytosanitary certificates and allow Technitubers to be utilised within interstate seed schemes and overseas markets.

Utilising Technitubers

Technico will not simply produce Technitubers and sell these from the 'factory door'. The potato industry is not generally familiar with the field practices required to plant and successfully grow a potato crop from miniature seed potatoes of Technituber size. The company is therefore currently developing an agronomic package to support the field planting of Technitubers.

Field trials conducted over the last two seasons have demonstrated that with modified agronomic practices, Technitubers can be planted in the field and grow to produce a vigorous, high yielding plant stand. A comprehensive research and development program will assure the continued high performance of the technology.

Technico has also demonstrated that a slightly modified vacuum seeder is capable of planting sprouted Technitubers at accurate placement, in singulated form, and without any damage to sprouts.

Initial commercial developments

In order to fund the initial scale-up to commercial production, Technico approached the Australian Technology Group (ATG). ATG is a private venture capital company that supports the commercialisation of Australian technology. It was set up in 1993 with the aid of Commonwealth government funding. ATG invests in technology-based companies, taking equity in the company and assisting during the early stage of the company's development.

The funds provided by ATG are being used to build a production facility in New South Wales to produce the potato seed tubers for both domestic use and export, mainly to Asia and the Middle East. The facility will be operational by January 1996. The company is also planning to establish production facilities internationally.

In May 1995, an international license agreement was signed with food and beverage giant Pepsico Inc. This will see Pepsico implement the new technology on a global basis for their requirements of seed potatoes in the Crisp (snack food) market. The agreement will produce substantial royalty revenues for Technico, and result in a boost to Australia's export earnings.

Under the agreement, Pepsico Foods International and related corporation Frito Lay, which have a substantial presence in the international crisp (snack food) market will further develop and assist Technico in the international commercialisation of the technology. Through the use of a flexible production system, production facilities can be situated in strategic locations throughout the world.

Future seed potato possibilities

One of the most prospective areas in the global potato industry for the development of improved seed potato technology, is in Asia. Asia has over half the world's population. Increasing income levels and increasing demand for potatoes and potato products (eg. French fries and crisps), means that there is tremendous potential for expansion of potato production.

Many of the Asian markets are currently supplied with seed potatoes from the Netherlands, and to a lesser extent Scotland. An article in the most recent addition of Potato Australia (published by the Australian Potato Industry Council), stated that: "Over the ten year period from 1980 to 1990, the area of potatoes cultivated in Asia has increased by more than one million hectares. The average yield of potatoes in Asia is 13.6 t/ha, which although comparing favourably with the world average of 14.8 t/ha, is less than half the average yield achieved in the USA (29.9 t/ha) or Oceania (29.8 t/ha)".

Shortage of good quality seed is recognised as the single most important factor inhibiting potato production in Asia. It is generally agreed that the low yields being achieved are the direct result of poor quality seed and the absence of an adequate system of seed production. This is not only affecting current production, but is also impeding future expansion of the fresh and processed potato industries.

The amounts of seed needed to substantially improve productivity per hectare cannot currently be produced. Even under the most favourable seed production conditions found in Asia, four to five field multiplications causes the progressive deterioration of seed through an accumulation of viruses and various soil and tuber borne pathogens. Under these conditions, there is obviously tremendous commercial potential for adoption of processes, which will allow for production of affordable seed potatoes from significantly reduced field multiplications. With Technico's technology, the opportunity now exists for a change in seed potato production in Asia, via regional Technituber production operations.

With keen interest in the technology now being expressed by a wide range of companies, governments and industry sectors, Technico is confident that further agreements will be finalised in what is an exciting future for the company.