Your Guide to Hybrid True Potato Seeds in South Africa
“We believe that the formal introduction of hybrid true potato seed in South Africa will bring great value to both commercial and smallholder potato farmers.”
– Justin Platt, MD of RegenZ
What's in this guide?
The value of hybrid true potato seeds in South Africa
Potatoes are one of South Africa’s most important vegetable crops:
Potato production makes up 45% of South Africa’s total vegetable production
Of potatoes planted per year in South Africa
Potatoes are cheaper, healthier, more nutritious, more vitamin-rich and water-efficient than other staple crops such as rice, soy and wheat. Potatoes can also be processed and cooked into so many different forms. So, why isn’t the world fuelling on potatoes?
Firstly, potatoes can be a challenging crop to grow. Potatoes are typically produced from seed potato tubers rather than true botanical seeds (which are generally unreliable). But seed tubers are bulky, perishable and disease-prone. Tubers that are not appropriately certified are especially susceptible to degeneration and contamination.
You may wonder why scientists haven’t bred better potato tubers to propagate. The truth is that potatoes have a complex genetic structure and are difficult to optimise through breeding. Potato breeding techniques lag far behind other popular crops such as rice, maize, and wheat. This is because potato breeding suffers hindrances through its genetic complexity, resulting in slow progress. For most potato breeders, selective breeding is the only option. But selective breeding doesn’t allow breeders to respond rapidly to new challenges.
So what’s the solution? The good news is that RegenZ has access to revolutionary new breeding technology that will help solve these problems: hybrid true potato seeds (HTPS).
What is hybrid true potato seed (HTPS)?
A true potato seed (TPS) is an actual seed from the fruit of the potato plant. A hybrid true potato seed (HTPS) is a cross between two homozygous parents that results in first-generation (F1) botanical potato seeds that are genetically identical.
HTPS breeding is new technology enabling potato seeds to produce predictable and consistent offspring. With South Africa’s reduced farming land area, limited water resources, and high cost of chemical inputs, hybrid true potato seeds offer the best starting material for healthy potatoes and good yields. These nutritious, easy-to-grow potatoes are abundantly available to fight food insecurity.
A quick lesson on genetics
Potatoes are typically grown from seed tubers saved from the previous year’s harvest. To grow potatoes from true seeds, a flowering potato plant needs to be inseminated so that small fruit develop into berries filled with potato seeds. These seeds are called true potato seeds. Although breeders have tried to use true potato seeds as starting material, potatoes have almost 40,000 genes, so crossing them results in entirely random, heterogeneous true potato seeds. This means that potato plants grown from true potato seeds will develop completely differently; some will mature early, others will mature late; some will bear tubers, others will not. This isn’t feasible for successful propagation.
The cultivated potato has four sets of chromosomes (tetraploid). This makes it easy for unfavourable alleles (matching genes) to make their way unseen into the next generation. It also means that introducing new, favourable traits can be very tricky.
What’s the difference with HTPS?
With hybrid true potato seed, genetic variety is reduced to allow the production of a standard product with only the desirable traits. This means that stable potatoes can be grown from seed, not only from seed tubers.
Removing the randomness with hybrid breeding
Hybrid breeding can remove the unwanted randomness generated by true potato seeds. Hybrid true potato seed breeding technology works by sexual propagation, crossing elite lines of male and female parent potatoes and producing new hybrid offspring that share the top features of both parents. What makes this approach so interesting is that it’s actually completely natural, something a bee could do if it knew which plants to visit. This hybrid breeding process was invented and patented by hybrid potato breeding company Solynta, based in the Netherlands.
What are the benefits of growing potatoes from hybrid true potato seed?
Allowing the rapid selection and turnover of favourable traits could help feed millions of people worldwide. The innovative targeted breeding will change the production and global distribution of potatoes by allowing for the combination of beneficial traits from different potato varieties to make elite progenies which have
- Higher yield
- Greater disease resistance
- Better taste
These plant variety rights give the breeder exclusive control over the propagating and harvested material of a new variety for a number of years. This provided the owner of a variety with the opportunity to make money from his or her efforts.
Here are some of the many benefits of HTPS breeding:
Growing at scale by quickly producing clean seed
In traditional potato production, the starting material is taken from already developed tubers. Each tuber produces about ten tubers, which need to be stored in acclimatised conditions for planting the following year. In contrast, using the hybrid breeding system allows each female plant to make about 5,000 seeds that can create a further 25 million seeds a year. If a farmer sows all these seeds, they can produce up to 250 million first-generation tubers.
Reduced size, weight and logistics
HTPS required for one hectare of potatoes
Tubers required for one hectare of potatoes
One of the most significant benefits of using HTPS over tubers is the simplified logistics, environmental sustainability, and reduction in transportation cost due to the decrease in weight and size. What was once shipped in trucks can now be shipped in an envelope!
The weight of 100 potatoes = the weight of 16 million seeds
Free from disease
On top of the logistical and transportation benefits, hybrid true potato seeds offer phytosanitary advantages. Potato seed tubers can carry pathogens along with infected soil, which is why the import and export of tubers are strictly regulated. On the other hand, hybrid true potato seeds are produced in a controlled environment. The parent stock is free of disease, which means that the resulting offspring is also free from disease. As a result, hybrid true potato seeds can be transported across the world easily like any other vegetable seeds. HTPS also stay healthy for years without special storage conditions (able to withstand changes in temperature and humidity), unlike perishable tubers, which can degenerate quickly if not stored properly.
More efficient potato breeding
With HTPS, first-time potato breeding has become more targetable, predictable, fast and efficient. Hybrid breeding could unlock hybrid vigour for the first time.
Solynta’s yield potato estimates with HTPS within ten years
Increase in potato yield in the developed world
Increase in potato yield in the developing world
Easy to manipulate traits
To make improvements with additional traits
With the hybrid breeding system, it’s relatively easy to enrich an existing hybrid with specific desirable traits while keeping all the other elements of that particular variety intact. For example, in only two years, Solynta developed a potato variety with genes resistant to late blight. Stacking beneficial genes is one of the most important aspects of hybrid breeding, as it continually enables breeders to improve varieties with beneficial traits. With the help of hybrid breeding technology, desirable traits can be harnessed, genetically selected, and reproduced:
- Robust varieties for harsh climates with excess heat and drought
- Varieties with salinity tolerance
- Improve taste and aesthetics such as shape, colour, size and skin texture
- Improve traits for processing, such as protein or starch content
- Reduce waste by optimising shape, storability, dormancy and bruising
- … the possibilities are endless
Faster selection of better potato varieties
Historically, selecting better potato varieties took a very long time. The first step was trial and error to breed a suitably stronger crop; after this, the selected plant would have to undergo a lengthy multiplication process. The best potato would be planted to multiply the number of tubers, which takes a year. The process would have to be repeated for about seven years until a commercially viable number could be produced. But during this time, potatoes could also become increasingly susceptible to diseases.
In contrast, the new targeted hybrid breeding process is able to counteract these historical problems:
- The HTPS breeding process uses diploid potatoes rather than tetraploid, resulting in a hybrid potato plant with just two sets of chromosomes
- The diploid germplasm is repeatedly bred with itself to dilutes the level of heterozygosity of the progeny
- After about six generations, progeny are almost completely homozygous
- By selecting only the most vigorous potato plants, the parent lines quickly become stronger and more homozygous
- These strong parental plants can be hybridised to make F1 hybrid seeds
Hybrid breeding is thus able to deliver a more predictable and continuous flow of improved products compared to the limited advancement of traditional potato breeding.
Discovering traits and improving potatoes
With a steady flow of strong, diploid potato plants, breeders can focus on isolating and selecting for desirable potato traits using sequencing and statistics to determine particular phenotypic traits. Plants with desirable genome alterations are then selected for breeding. Parental lines can also be backcrossed to add new hybrid traits to the parent lines. Strengthening the parent lines allows hybridisation to an even stronger, tastier, or larger hybrid potato. This process has been accelerated for the first time due to the speed of growth from seed and the genetic selection of traits.
An answer to nutrition security challenges
Hybrid true potato varieties have been developed to answer the world’s nutrition security challenges. The non-GMO, disease-free potato seed produces nutritious and delicious potatoes that require fewer pesticides to produce great yield, thus allowing for more regenerative farming practices. The easier logistics and lower cost also make hybrid true potato seed a viable solution to help farmers and feed people in challenging circumstances.
While the benefits are massive for higher-income countries, they are even more significant for low-to-middle-income countries. Solynta has already conducted trials in East Africa, which resulted in much higher potato yields using HTPS instead of seed potatoes.
Benefits of HTPS for central and southern African countries
- Seeds are extremely easy to transport
- Free of the pathogens which tend to thrive in the tropical African climate
- The ability to adapt the diploidisation and genetic hybridisation techniques to African potato varieties
The future of HTPS in South Africa
Great advances have already been made in the development of useful homozygous inbred lines as well as the technologies to develop new cropping systems adapted to various agronomic practices and climatic conditions.
Future developments could include:
- Similar to modern tomato hybrids, hybrid potato varieties will be able to harbour up to 15 resistance genes
- The lifetime of new potato hybrid cultivars will be reduced to less than five years (like the hybrid sugar beet)
- Inbred lines will of great value for genetic and genomic studies, as has been shown in other crops
- Self-compatible potato inbred lines will stimulate quantitative research on the genetic control of complex traits such as interaction with biotic stresses, mycorrhiza, nutrient uptake, processing quality and nutrition value
- New players in the scientific and applied breeding field will be able to take full advantage of the hybrid breeding technology in science and product development
RegenZ’s hybrid true potato seed partnership with Solynta
RegenZ and Solynta have partnered to bring hybrid true potatoes to the South African agricultural community. Both RegenZ and Solynta are committed to developing sustainable farming innovations that improve quality of life.
“We believe that the introduction of Solynta’s innovative hybrid potato technology in South Africa will bring huge benefits to the potato-producing farming communities,” says Justin Platt, Managing Director of RegenZ. “We see from Solynta field trials in the region that the technology can contribute to more efficient and sustainable potato production. Hybrid true potato seeds can address food security goals in line with South African government objectives. With their unique ability to build in disease resistance, Solynta’s hybrids will deliver a predictable and rapid flow of improved products. By delivering these genetics through true seeds, many other advantages will be achieved, such as the provision of disease-free seed and a reduction in storage and transport costs.”
With HTPS, Southern African farmers will benefit from using the best, clean and disease-free starting material for their potato production. We look forward to working with Solynta to introduce potato cultivars that will thrive in Southern Africa. It’s only a matter of time before these innovative farming methods are used worldwide to catch up with the global demand for food production as the human population continues to expand.
Get in touch with the team to be the first to be informed about HTPS availability in South Africa.