Maize varieties grown
Both local and improved varieties are grown in Burkina Faso. However, local maize varieties are the most predominant. It was noted that only 15 out of 32 released improved varieties are produced by seed growers. Many varieties were named by the breeders in local language with the aim of facilitating the adoption; for instance variety “wari” means “money” in Dioula. In some instances, the same local varieties are known by different names and different improved varieties had a common name, depending on the area or language. The names of the maize varieties are mainly descriptive as they refer to certain key identifiable characteristics. This result was consistent with that reported by Sanou [7] who showed that famers name maize varieties in their own dialect using one or more distinctive characteristics. For instance, kaba gè (white maize in dioula), Vagaka pènin (yellow maize in bobo) and Kaman gnanga (late maturing maize in mooré). The consistency in the two studies shows that, after 15 years, farmers still name their varieties by key characteristics and not the name given by the breeder. White maize varieties are mostly preferred and the early maturing varieties are largely grown. However, the notion of early maturity has to be taken with caution because famers and researchers do not understand it in the same way. In general, farmers define the cycle (from planting to harvest) in months (2, 3 or 4 months) while the local maize breeding program set a range of days to define a cycle of a particular variety: extra-early (70–84 days), early (85–94 days), intermediate (95–110 days) and late (more than 110 days). Farmers do not classify a variety of 3 months maturity as an early variety whereas breeder assign it in early maturing group. The popularity of early varieties has implications for breeding. Hence, breeding programs should consider improving early varieties with a wide adaptation, instead of trying to develop these varieties only for the dry areas. The analysis of the grain color of the varieties shows that farmers will adopt new varieties if they fit their preferences regardless of grain color. The few number of late maturing yellow varieties in the two zones is also very revealing. Maize breeding programs have released only one late yellow maturing variety; hence, famers will more likely adopt new late maturing yellow varieties.
Constraints to maize production
Drought is a major abiotic constraint affecting maize production in Burkina Faso. Climate instability has resulted in variation of the intra-and inter-annual rainfall and made drought a recurrent problem. This was acknowledged by famers in the two agro-ecological zones. Drought is characterized by an unequal distribution of rainfall in both time and space. Results show significant difference in drought ranking between the two zones. In South-Sudan zone (annual rainfall is above 900 mm), drought is perceived to be more important than in the north-Sudan zone (annual rainfall is between 600 and 900 mm) because, during long season (South-Sudan zone), two frequent drought periods are generally observed. One is at seedling stage, during the period that many famers plant when the first rains fall, but, unfortunately, the rains may stop after one to two weeks. The second drought occurs during the grain filling stage. In short-season areas (North-Sudan zone), plants are more subjected to drought just after planting. Maize varieties, Barka and Wari, tolerant to drought, extra-early and early maturity, respectively, are generally grown in North-sudan zone. This could explain why drought is perceived as being less important in this area compared to the South-Sudan zone where late maturing maize varieties are grown but no drought-tolerant-improved varieties have been released. Low soil fertility is another abiotic constraint that farmers are dealing with in Burkina Faso. There are highly significant differences across agro-ecological zones for low soil fertility. In Southern Sudan zone, the problem is perceived to be more important than in Northern Sudan zone. In the North-Sudan zone, maize is mainly cultivated around houses, dams and rivers where the soil is more fertile, while, in South-sudan zone, even though maize is grown around the houses, most of the production is done in fields far from the village and, due to the limited resources, few inputs are used. Recurrent drought and declining of soil fertility, particularly nitrogen, imply that breeders should develop drought- and low N-tolerant maize varieties. Farmers ranked Striga as the major biotic constraints to maize production in both agro-ecological zones. Striga hermonthica is a root parasite of grasses occurring throughout Burkina Faso. It is an important biotic constraint to maize production in the country and is the weed that farmers fear most. Striga became an important constraint to maize production recently due to increasing maize cultivation on land initially occupied by sorghum and millet. Control methods available for farmers are limited. Due to the limited resources, chemical control and normal fertilization are not affordable by small-scale farmers and there are no tolerant varieties released by research. Hand pulling and crop rotation are the only control methods accessible to small-scale farmers. Striga control methods developed by research are often unknown and unexploited by farmers. Striga, which was not a major constraint to maize production in Burkina Faso 20 years ago and was limited to the dry areas (North-Sudan), appears now to be a major constraint all over maize production zones and a big challenge for maize breeding program. The implication is quite clear, demand for resistant Striga varieties is real. Breeding program should develop new varieties tolerant to Striga and/or improve existing adapted varieties for Striga resistance. Attack by termites in farmers’ fields is another major problem to which less attention is paid by research. Farmers indicated that they adopted a range of solutions without realizing a substantial impact. The problem needs to be addressed in the two zones (North- and South-Sudan) using an integrated pest management approach. Among the constraints which cannot be addressed with improved or tolerant varieties, famers rank poor cash flow problems, inadequate farm tools and poor extension service as important. Agriculture in Burkina Faso is mostly dominated by traditional farming, characterized by the use of ‘‘daba’’ (an African hoe) and animal traction. Farming knowledge is learned in the family from generation to generation and most of the time farmers do not have access to modern knowledge and new technologies developed by research. As a result Governments, NGOs, and Research Centers have adopted strategies to teach farmers about farming systems. Different methodologies have been developed: formal training sessions, field demonstrations, broadcasts in radio and TV and booklets in official (French) and local languages. However, the results of the present study indicate that a lot needs to be done to reach farmers, especially small-scale famers in the remote villages.
Farmers’ choice of varieties
The grain color is the first criterion used by farmers in selecting maize varieties. This does not mean farmers are interested only in the color, rather it reflects that key characteristics, especially grain color and cycle of maturity, used to identify maize varieties. For farmers, the grain color represents some features, especially yield, of a particular variety. Grain size is an important criterion for varietal selection, thus farmers always select seed with the large grains size to grow. High yield is generally the first trait desired by farmers, followed by early maturity. These results have important implications for breeding: early maturing and drought-tolerant varieties should receive more weight in the breeding for all the agro-ecological zones and not only for the dry areas.