1. Introduction
Pearl millet (
Pennisetum glaucum (L.) R. Br.), a climate-resilient cereal, is an important food crop in the dry regions of the Sahel. The majority of the cultivated area of pearl millet is in Africa (~18.0 m ha), Asia (~10.0 m ha), and the Americas (~2.0 m ha) [
1]. In Niger, pearl millet production has reached 3.5 m tons, making Niger the largest pearl-millet-producing country in Africa [
2]. This crop accounts for three-quarters of the cereal production and over half the cultivated land in Niger [
3], and the highest per capita consumption of millet is in Niger [
4].
Pearl millet grains have higher levels of grain Fe and Zn contents when compared to wheat and rice [
5]. The energy density of pearl millet is also relatively high, arising from its higher oil content relative to maize, wheat, and sorghum [
6]. Despite these properties and being the central component of food security in dry areas [
7], people in Niger are affected by poor-quality diets, resulting in micronutrient malnutrition from Fe and Zn deficiency. To address malnutrition, biofortification has been described as a cost-effective (only requires a one-time investment) and sustainable strategy that provides a long-term positive effect [
8]. Through HarvestPlus, which is part of the CGIAR Research Program, many biofortified varieties have been released to combat hidden hunger, i.e., beans with Fe, pearl millet with Fe, cassava with vitamin A, maize with vitamin A and Zn, sweet potato with vitamin A, rice and wheat with Zn [
9]. In Niger, the improved high-iron pearl millet variety “Chakti” was released in 2018, and efforts are underway to scale up Africa’s first Fe-biofortified pearl millet variety. Moreover, pearl millet’s most widely cultivated variety HKP in Niger was found to have low grain Fe and Zn contents compared to the biofortified varieties.
Although several high-yielding varieties were released in Niger (around 30 improved varieties) [
10], their adoption has been very poor because of the underdeveloped and undertrained seed systems in this region [
11]. According to the 2019 annual yearbook only eight improved varieties were available for the rainy season in 2019. The HKP variety alone accounted for 90% of improved seeds available, followed by SOSAT-C88 (6%), whereas other improved varieties accounted for only 4% [
12]. It was reported that less than 2% of the total national seeds planted by farmers are supplied by formal seed systems [
13]. Hence, the focus should be placed on seed systems using seed-based projects, while varietal development needs to be accelerated using participatory approaches to engage farmers and in utilizing the quality seeds of improved varieties and hybrids.
There is strong confirmation for the hypothesis that the insufficient priority given to consumer-preferred traits by breeding programs contributes to the limited uptake of modern varieties and low varietal turnover [
14]. In Sub-Saharan Africa, farmers are most often the consumers of the food crops they grow, and they, therefore, have developed particular preferences for the crops they grow to match their food types and needs. Buerkert et al. reported a preference for pearl millet varieties with long panicles in the Sahel, as they provide an important advantage for Sahelian farmers whose mode of transport (on camel or donkey backs) and commerce are based on millet bundles (botes) that contain up to 200 similar long panicles tied together [
15]. For grain shape preference, the classification of the pearl millet species of the world based on seed shape indicated that the Globosum race was the most common race found in central Nigeria, Niger, Ghana, Togo, and Benin [
16].
To our knowledge, no investigations concerning the adoption and acceptance of released and pipeline-breeding high-iron pearl millet varieties have been conducted in Niger. Therefore, this participatory rural appraisal (PRA) study was conducted to understand whether farmers in Niger would prefer varieties with added nutritional value, along with the gender-based trait priorities for breeding. In addition, other attributes that farmers prefer and the trade-offs between the nutritional and other important production/consumption attributes were evaluated. The study also aimed to segregate and record the trait preferences on gender basis.
4. Discussion
Considering the semi-arid farming practices and food system, pearl millet plays an important role in food and nutrition security in the Sahel region. This is well reflected in the results of FGDs in the Dosso region of Niger. In the Dosso region, pearl millet cultivation is dominated by men. During FGDs, women in Deytagui Noma stated that when the patriarch was absent during traveling, they were not allowed to sow pearl millet during the rainy season. Additionally, in Tara and Bozawara Kore, women disclosed that they participated in farming activities but did not own the land or decide on cropping. Kanfany et al. (unpublished) also stated similar findings for the groundnut basin in Senegal, where men dominate crop production activities, while women provide operational support.
Interestingly, all farmers in the Dosso region grow two types of pearl millet varieties (late- and early-maturing); they stated that at the beginning of the rainy season, their pearl millet grain stocks are depleted, and an early variety is the only option to provide food grains for their consumption, while the late-maturing variety serves as the major part of their pearl millet production, consumption, and markets to some extent. A similar pattern of practices was reported in Ghana, where pearl millet was harvested at the peak of the rainy season when the farmers’ stocks of food grains from the previous harvest were exhausted [
19]. The whole farming community (98%) used pearl millet seeds from their own stocks by selecting the best-looking panicles for planting during the following rainy season. Therefore, in this region, farmers underutilized the adaption of improved varieties. However, farmers’ selections of trait preferences and maturity within varietal bulks are very critical. In fact, artificial selection coupled with natural selection practiced in pearl millet has led to the development of well-adapted local landraces in the semi-arid region of Africa [
20].
FGDs revealed that low grain yields are characteristic of most of the farmers’ landraces that produce close to 0.5 t/ha. These findings are in line with Guengant and Banoin, who reported an average pearl millet grain yield of 400 kg/ha in Niger for five decades (1955 to 1999) [
21]. Around 96.6% of the farmers reported using largely organic fertilization or a combination of organic and mineral fertilization but were reaping low yields per unit area using local or traditional landraces (haini kiré, darancoba, zongo, omno, etc.), which highlights the need to replace landraces with improved and high-yielding varieties from the ICRISAT and NARS breeding centers.
Regarding the pearl millet varietal and grain preferences, the results revealed that earliness was the most preferred trait by both men and women farmers irrespective of the department. The survey also showed that a good seed set (seed covered > 80% of panicle) combined with a long panicle (>50 cm long) accounted for 96% of the preferred traits. In breeding, both the seed set and long panicle are correlated with the yield per unit area, which suggests that the farmers will likely adopt an early variety with a long panicle and good seed set for better yield [
22,
23]. Most of the farmers had heard of improved varieties and reported having received seeds of improved varieties. However, these were lost after a few years, probably due to the millet seeds produced by the outcrossing (>80%) reproductive mechanism facilitated by their protogynous nature (the stigma emerges first). There were opportunities to mix seeds with landraces in the household since practicing farmers selected seeds from their own stock. All respondents were willing to purchase improved pearl millet varieties if available in a timely manner in local shops or from suppliers irrespective of the seed cost, which suggests that improving the supply chain of improved pearl millet seed will ensure the seed replacement rate in pearl millet and thereby promote higher regional production to cope with household food and nutrition security.
For pearl millet production constraints, apart from the cultivar choice, the FGDs and questionnaire survey revealed that poor soil fertility was the most important constraint on pearl millet production in the Dosso region. Soil fertility is a major constraint for countries across west and central Africa, where semi-arid to arid conditions historically exist. Earlier studies reported that poor soil fertility and the limited use of organic and mineral fertilizers were the most important constraints on increasing agricultural productivity in West Africa [
24]. In West Africa, farmers traditionally used long fallow periods to restore soil fertility. However, less land is available due to the growing population, making these practices ineffective [
25].
The second most important constraint was drought. Pearl millet production is mostly practiced on marginal lands with scanty rainfall and drought stress, which represents a major constraint on the grain yield in these farming systems [
26]. Efforts have been made to increase the pearl millet yield through mineral fertilization and the selection of early-maturing varieties that escape late-season drought [
27]. Early-maturing pearl millet varieties have a low water requirement, which enables relative drought escape, mostly at the end of the season [
28]. In addition, drought stress was found to cause a reduction in the pearl millet seed size. This reduction was mainly due to the reduction in the endosperm component of the grain, making the grain layers a major proportion of the seeds [
27]. Annual precipitation can be very low (373.8 mm) and occur in a short span (37 days), which is a big constraint that requires the strengthening of natural and local water reservoirs [
17]. This will drive improvements in soil fertility by growing multiple crops or drought-tolerant trees that provide organic matter to fields and support integrated farming.
The parasitic weed
Striga hermonthica was the third most important constraint on pearl millet cultivation in this study. The farmers reported that they mostly observe striga in farms that have been used for cultivation for a long period. This is consistent with Vogt et al., who reported that striga preferentially occurs in nutrient-poor soils that have been exhausted by continuous cropping [
29].
Due to the local perception of malnutrition and dietary diversity, in Deytagui Noma, women suffering from anemia visit the hospital to receive fortified biscuits. Elderly women reported that, during their youth, they used to prepare special porridge for new mothers and their babies. In Tara and Bozawara Kore, women still prepare porridge for new mothers. In Tara, porridge is prepared from whole pearl millet grain, sorghum, sesame, groundnut, and dried fish. Meanwhile, in Bozawara Kore, they use sesame, roselle, squash, and cowpea to prepare porridge for breastfeeding mothers. Across all sites, men associated malnutrition with a lack of satiating hunger, while women at all sites were aware of hidden hunger, especially anemia. Anemia is referred to locally as a “lack of blood”, a term used by nurses to explain anemia to new mothers. The expression “lack of blood” refers to the insufficient number of red blood cells or their incapacity to bind oxygen. Iron has many key functions due to its role as an electron donor/acceptor in the human body and is a core part of oxygen transport through the heme complex, which is found in oxygen-binding hemoglobin molecules in red blood cells [
30]. To produce hemoglobin, Fe is a major required constituent; it is proven that the consumption of biofortified pearl millet cultivars will provide more than 60% of the daily Fe requirement [
5,
31].
For instance, the majority of the farmers consumed pearl millet on a daily basis (98%) and consumed at least 3.57 kg of pearl millet weekly, which might suggest that increasing the density of micronutrients, especially iron and zinc in pearl millet grain could reduce iron deficiencies in the Dosso region. Meat and dairy products were more often consumed in the Dogondoutchi department, whereas they were less often consumed in the Gaya department, mostly because, among the three departments, livestock production is the highest in the Dogondoutchi department and the lowest in the Gaya department [
17]. All survey respondents were willing to try improved biofortified pearl millet for their children and breastfeeding women. In addition, according to Welch, increasing the quantities of micronutrients stored in seeds can result in improved seedling vigor and viability when these seeds are sown in micronutrient-poor soils, thus enhancing the performance of seedlings during crop establishment [
32]. However, 99.3% of the surveyed farmers reported practicing the decortication of pearl millet grain before consumption. Decortication is commonly performed with abrasive disks in mechanical dehullers. Pearl millet grain is usually decorticated of the bran (pericarp) from the endosperm before being consumed in Niger [
15]. In a study conducted by Hama et al., they found that half of the iron content was removed when 10% of the pearl millet dry matter was abraded [
33]. In fact, the removal of the bran leads to a decrease in the nutrients, including minerals and anti-nutrients, as these are mostly situated in the peripheral area of the grains (pericarp and aleurone layers).