This past spring I received an invitation to assist the Agricultural Development Corporation (ADC) in Kenya to establish routine ELISA testing and Tissue Blotting Immunoassay tests or TBIA. The assignment was sponsored by CNFA, a non-profit organization in Washington, D.C. and the grant was provided by USAID. ADC is a parastatal organization in Kenya, similar to a quasi-government organization.
Potatoes are the second major crop in Kenya after maize. ADC has the capacity to produce about 5 percent of the seed potatoes needed in Kenya. This would be certified seed, but there is a lot of farmer to farmer seed that is also used. Currently, over 110,000 hectares of potatoes (271816 acres) are grown in the country, mostly in the highland areas of western Kenya. The elevation of the Molo region is 8200 ft.
I was there the last three weeks of June (their winter) and temperatures were a comfortable 60-70°F. Kenya is bisected by the equator and has a mild climate. July is their coldest month during winter.
They have two crops of potatoes each year and the crops are all rain fed. There are two rainy seasons, the short rains, October-December, with intermittent showers and some flash flooding and the long rains, or heavier rainy season, from April to May. The first crop is planted from mid-March through April and harvested in July and August. The second crop is planted from mid-October through November and harvested in mid-February through March.
I was able to see the first crop as it was at the peak of flowering, which is a good time to check for viruses and other diseases. While at ADC, I was able to watch some harvesting where the potatoes were dug with a digger that laid the potatoes back on the ground and then were picked up and bagged in standard 70 or 90 kg bags.
Harvested potatoes were typically put into 150-170 kg bags (330-375 lbs) and placed at the roadside for pickup. I watched as up to six men would load each bag into a truck for transport.
The issues that the growers there deal with are something that many seed growers are familiar with – viruses such as Potato virus Y and leafroll virus. They also deal with late blight and bacterial wilt (aka brown rot) caused by Ralstonia solanacearum.
For Kenya’s certified seed growers, bacterial wilt is treated as a zero tolerance disease and inspections for viruses and bacterial wilt take place during the summer and in post harvest test plots administered by Kenyan Plant Health Inspectorate Services (KEPHIS).
Varieties grown in the country include Kenya Mpya, Kenya Sherekea, Asante, Kenya Karibu, Tigoni, along with others such as Dutch Robjin and Desiree. Interestingly, in Swahili, Mpya means new, Sherekea means celebrate, Asante means thanks, and Karibu means welcome. Some of these originated from International Potato Center and were selected for Kenya.
— By Jonathan Whitworth
Jonathan Whitworth is a plant pathologist for the Agricultural Research Service in Aberdeen, Idaho.