kari primes potato sector with fast-track tuber growing technology

The Kenya Agricultural Research Institute (KARI) has introduced a new farming technology for breeding multiple disease free potato tubers in a bid to achieve a widespread take-off in productivity for the country’s potato farmers.

In Africa, according to 2007 report by Food Agricultural Organization (FAO), Egypt has the highest potato output at 2.6 million tonnes. Kenya ranks as 8th in potato production, harvesting around 0.8 million tonnes a year from an estimated 120,000 hectares. This translates to an average yield per hectare of 6.7 tonnes of potato yields.

But output could be many times higher, says KARI, which reports that currently only 1 to 2 per cent of Kenyan farmers are using certified potato breeds. Over 90 per cent of Kenyan farmers still plant potato varieties that at optimum yield only 7 to 10 tonnes a hectare. The varieties are also susceptible to diseases and virus attacks and are not economical in the long run.

But the challenge of getting good breeds to farmers is hampered by the low numbers of reproduction laboratories in Kenya. Only the Agricultural Development Corporation in Molo and Kisima Farm in Timau are breeding new potato varieties.

Meanwhile, many private breeders shy away from commercial potato tuber reproduction due to the costs involved. Most local private breeders opt to breed for seeds such maize, which are less expensive.

KARI now hopes that by importing a high-yield potato breeding technology it can attract more private breeders into the industry. Dubbed aeroponics, the new technology  grows potato tubers in “air” without the use of soil.

Adopted by KARI from Lima in Peru last year, the technology is an improvement on the conventional way of breeding potato tubers from the soil. In Peru it was introduced by the International Potato Centre (CIP).

The tubers are grown in liquid chemical solutions with extra nutrients and chemicals that increase the tubers’ disease resistant. The extra nutrients include potassium nitrates, calcium and phosphate minerals.

The technology consists of a meshed box partitioned into two. The partition has holes through which the tuber plantlets grow up. The tubers themselves, in the lower box partition, produce an extensive root network with maturing tubers.

The lower box has a timed mist spray that releases liquid nutrients every 5 minutes. The lower box with tubers is wrapped with a black plastic to create darkness but is aerated to ensures the tubers efficiently absorb the oxygen and carbon dioxide they need to grow. The aeration results in more tuber production.   

According to Joseph Ngaruiya, the project specialist, using aeroponics guarantees a farmer five times more tubers per plant compared to when tubers are planted in the soil.

Also “it guarantees sequential harvesting of tubers for 6 months,” said Ngaruiya. Tubers planted in the soil guarantee an optimum 3 months of yielding tubers. Tubers grown in the soil are also vulnerable to pest and disease attack. The screen house enclosure of the aeroponics technology prevents these.

At KARI-Tigoni, the technology has been tested using a 15m by 5m meshed box with 600 plants. Each plant is capable of producing 50 tubers. That amounts to 30,000 tubers being produced for later transplanting in the six months.

When KARI first trialed 5000 of these tubers on a piece of land, they harvested 14 bags each of 50 kilograms on the first harvest. For second and third generation harvest for similar tubers, they forecast yields of 140 and 1400 bags respectively. With each 50kg bag averaging Sh1000 at the market, farmers can make Sh1.4 million.

However, the technology is pricey: a 15m by 5m screen box with its associated accessories for irrigation costs just over Sh250,000. The Aeroponics nutrient solution can be sourced from Amiran Stores in Nairobi, and costs around Sh4000. KARI’s Tigoni potato research centre offers technical assistance on mixing the solutions.   

By introducing this technology to Kenya, KARI hopes more quality; disease free tubers for transplant will be produced to feed an overall upgrade in the country’s potato harvest.. For more details on the technology contact KARI- Tigoni station at This email address is being protected from spambots. You need JavaScript enabled to view it. or call them on 0733 333223/333224, +254 722 206986/206988.

Written By James Karuga for African Laughter

• < Prev
• Next >