The Small seed plot and Select-the-best Technologies | Crop Management (Crop Varieties)
Despite of the increasing demand for potato and the great interest that farmers have in potato farming, the crop’s productivity has been declining owing to insufficient quantities of healthy, high-yielding seed of desirable potato varieties. It is recognized that potato-planting materials contribute about 40% of potato production input costs. Unfortunately, more than 95% of seed potato is sourced from farmers’ own harvests or markets or neighbours. Such tubers are often of poor health status owing to latent infections by Ralstonia solanacearum (the bacterial wilt causal agent), viruses and other tuber-borne pathogens. Main constraints to seed access include high transaction costs with (43.5%), limited seed availability (40.5%) and limited information on the source of seed (14.0 %). Therefore, increasing the availability of high quality seed potato to farmers, coupled with enhanced management of tuber-borne diseases to reduce quality deterioration, would be a major step towards increasing potato yields and making the potato value chain more competitive.
The seed-plot technique utilizes the principle of maximising tuber production per unit area of limited, disease-free land through high-density planting in seed plots (synonymous with a ‘nursery’). This is achieved by planting well-sprouted seed potato tubers on selected disease-free land on plots measuring 1.8 m wide and a length of not less than 9 m at a spacing of 30cm by 30cm and nurturing the plants up to maturity to obtain seed for the following season as opposed to obtaining seed from ware potato fields where plants are spaced more widely (70 x 30cm in Uganda; 75 x 30cm in Kenya; 80x 30 cm in Burundi). The plots are deeply dug to loosen the soil and then raised to about 15 cm high. Carefully selected tubers obtained from seed plots can then be planted at the usual spacing for ware potato production while at the same time reserving some for the establishment of more seed plots. Field activities include weeding, hilling-up with soil obtained from estimated free from bacterial wilt pathogen land, pesticide application to control pests and diseases as appropriate, dehaulming at plant senescence, harvesting 2-3 weeks after dehaulming, sorting to remove damaged and diseased ones, grading for size separation).
The positive seed selection technique has the principle of selecting the best plants in a ware field (planted at the usual spacing) as mother plants to provide seed for the following season coupled with the removal and disposal of diseased plants as soon as they are seen. The process of selecting seed potato under this technology starts with the identification and marking of healthy-looking potato plants (using pegs) when the first flowers appear on the crop followed by checking the health status of the pegged plants two weeks later in order to removing pegs from the plants that exhibit disease symptoms; the plants that ultimately remain pegged are subsequently harvested individually, ensuring that plants with few tubers or those with malformed tubers are disregarded. The positively selected plants are harvested before the rest of the plants in the field and the seed kept separately for the subsequent season’s demonstration and use. Tubers obtained from all the other plants that are not positively selected in the target field are only used for home consumption or for sale as ware produce.
The infrastructural support for production of potato mini-tubers is now available in Uganda, Kenya and Rwanda. Private sector companies in Kenya and Uganda have taken up early generation potato seed production as a business and find a ready market. The Uganda National Seed Potato Producers Association among other farmer groups have also sprouted to produce seed for sale.
The gross margins comparisons are as follows (in Kenya Shs)
Table 6: Comparison of Gross margins before and after the Project
|Inputs/Output||Before the Project||After the Project|
|50kgs bags||10 @ 1000 =10,000||10 @ 2500 = 25,000|
|Ploughing||By oxen 1,800||By tractor 3000|
|Fertilizer 50kgs bags||2 bags @ 3500=7000||4 bags @ 2500* = 10,000|
|Planting labour||4x 200=800ksh||8x200=1,600|
|Top dressing labour||8x200=1,600|
|Fungicide||4,800 (curative)||8,000 (preventive)|
|Yield||50 bags||99 bags|
|Prices per 110-kg bag||2,000||Ware =2,800 & Seed 3,000|
|Total cost of inputs (KShs)||36,100||77,000|
|Profit (Kshs)||63,900 (US$ 752)||208,600 (US$ 2,454)|
I am a potato farmer from Kenya. My farm is on the leeward side of Mt. Kenya and it is in Timau Ward, Kirimara Location, Buuri Sub-County, Meru County. Potato growing is the main source of income in the area. Many farmers in our area experience low productivity due to lack of quality seed potato. This makes the farmers recycle seed potato from their own farm stores, which in most cases have tuber-borne diseases, e.g. bacterial wilt. Although the situation is still not at its best for majority of the farmers in the
area, there has been a great improvement for some of the farms through the intervention of an ASARECA seed potato project introduced to us by National Potato Council of Kenya (NPCK) and Kenya Agricultural Research Institute (KARI) in collaboration with the Ministry of Agriculture. Through the area agricultural extension office, the combined team of project implementers (NPCK and KARI) identified farmer groups for implementation of the project. The implementers informed farmers and agricultural extension officers
and other stakeholders that the project was supported by ASARECA. The team from Staple Crops at ASARECA participated with us in all the stages of the project implementation. They introduced technologies for improving the availability of quality seed potato, which were readily accepted by the participating farmers. These were: Seed-plot technique and Positive seed selection. In our area, six (6) farmer groups were identified. Each group was asked to select four (4) members to act as the lead persons in the implementation of the project activities; 2 members were trained as TOTs, 1 member was trained for hosting the seed-plot technique demonstration and 1 member was trained for hosting the positive seed selection demonstration. The TOTs and hosts of technol ogy demonstrations were trained on the various aspects of seed potato production and handling. After that the group members went to do the same on their plots (baby plots). After the training, practical demonstration were done on how the technologies work. Thereafter, group members were encouraged to do the same on their own farms with the guidance of the TOTs and supervision of the project team. The community around got very much attracted by the very good growth of our potato crop, especially in seed plot, and wanted to now more about the technology. Through the demonstrations, the community has realized the importance of quality seed potato hence improving the productivity resulting to increased income. The 6 groups came together and formed an association nown as Kirimara Potato growers’ Welfare Association. Kirimara is the native name for Mt. Kenya. So far, 6 members of the association want to be seed merchants and they have already started being trained to start certified seed in collaboration with KARI and KEPHIS. Through the use of higher quality seed potato, production in the area has increased and also created employment to our community members. Many farmers now can acquire clean seeds from their already existing farms through positive seed selection hence this seed is multiplied in a seed plot by the small-scale holders. The
ASARECA-support project came to our rescue when we did not know how to improve the availability of quality seed potatoes. The design of the project motivated farmers because they initially bought seed and after harvesting and selling the seed, NPCK and KARI rewarded the farmers by refunding the money. This has increased farmers income even more for further investment in seed production. Kirimara Potato Growers’ Welfare Association plans to become even bigger, have more members and increase our incomes.
Institut des Sciences Agronomiques du Burundi (ISABU)
P.O Box : 795 Bujumbura-Burundi
Nahayo P Claver,
Confédération des Associations de Producteurs Agricoles pour le Développement (CAPAD)
P.O Box 24. Bujumbura-Burundi
Tel : +257 22227902/+257 22273691/+25779967257/ +257 79 985 926
National Potato Council of Kenya NARL-KARI Campus, Waiyaki Way
P.O. Box 29982-00100, Nairobi, Kenya
Tel. +254722597389/ +254725673745/ +254 20 2338231
Zachary M Kinyua
Kenya Agricultural Research Institute (KARI) National Agricultural Research Laboratories, Kabete
P. O. Box 14733-00800, Nairobi, Kenya
Tel: +254 (0)20 4444144.
Cell phone: +254 733 999444 Email: email@example.com
Oggema Natabona Judith
Agricultural Development Corporation (ADC) - Seed Potato Complex – Molo
P. O. Box 47101-00100 Nairobi, Kenya.
Tel: +254 020-2250695,
Cell phone: +254 721 202565
Uganda National Seed Potato Producers Association (UNSPPA)
ASARECA TIMPS-Revised Nov 2014 Page 45
P.O. Box 329, Kabale, Uganda,
Mobile : +256(0)772657621 and 751657621
Kachwekano Zonal Agricultural Research and Development Institute (KAZARDI)
P.O. Box 421, Kabale, Uganda
Tel: +256 (0) 486426496 (office)
Mobile : +256 (0)782361597
Fax: +256 (0) 486426496
The mother and baby plot concept was adopted by farmer groups. Farmers learnt from the demonstration plot (mother) and replicated the same in their own farms (baby). Prior to the establishment of seed plots a training of TOTs, Positive selection and mother plots hosts were trained. The mother plot gardens per group were established using certified potato seeds. The baby plots established used both certified seed bought by individual farmers and that supplied by ASARECAS. Some farmers were unable to establish own positive selection plots due to limited land space whose rotation regime did not allow them to grow potato on wide scale.