Are dormancy management and physiological age the achilles' heel of aeroponic minituber production in seed potato value chains in SSA?

Scarcity of good quality seed is major obstacle to expanded potato (Solanum tuberosum L.) production in sub-saharan Africa (SSA). Constraints in availability and supply of seed potato are partly attributable to challenges in production of pre-basic which is an intermediary step necessary in production of seed tubers in the seed potato value chain. Aeroponic minutuber production is a relatively recent technology that has the potential to break the seed potato bottleneck in many SSA countries due to several advantages that it holds especially those related to high multiplication rates; typically (1:50-100) that arise from sequential harvesting. There are, however, a number of potential challenges which, if not addressed, can contribute to non attainment of the projected increases in seed availability and not only mess up the 3 generation (3G) revolution strategy of boosting seed tuber production in SSA but also jeopardize the adoption of the technology. Besides problems associated with failure of electricity supply and management of nutrition, the Achilles‘ heel of aeroponic minituber production is probably the large variation in physiological age of resulting tubers due to sequential harvesting that takes place over several months during the production cycle. In the absence of cold storage facilities which are few and beyond the reach of many pre-basic seed potato growers in many SSA countries, harvested minitubers can either be at dormant, apical dominance, multiple sprouting or senile stage when they are required for planting with significant impacts on subsequent yields. This paper discusses the problems associated with physiological age in seed tuber systems based on aeroponic minitubers and proposes some approaches that may overcome these challenges to ensure that the promise of aeroponic minituber production is realized. The proposed approaches include the strategic application of dormancy inhibiting and dormancy promoting substances at various stages of aeroponic minituber production combined with the use of low cost storage systems such as the diffused light storage technology depending on the dormancy period of the variety (ies) being grown

Rwanda Nutrition, Markets and Gender Analysis 2015: An integrated approach towards alleviating malnutrition among vulnerable populations in Rwanda

The Nutrition, Markets and Gender (NMG) Survey was conducted in Rwanda to investigate the causes of malnutrition in children under 24 months. The NMG Survey was informed by the 2010 Demographic Health Survey (DHS) for Rwanda that gave some insight into the knowledge and trend of malnutrition in the country for the period 2005 to 2010. The DHS results indicated a 6 percent decline in stunting among children under the age of five years. The key findings from the 2014/2015 DHS that followed the same delineation as the DHS 2010 provided the most current status of malnutrition in Rwanda and showed further overall improvements in child growth outcomes with 37.9 percent of children under five years classified as stunted. These results again indicated a 6.3 percent decline in stunting among children under the age of five years for the period 2010 to 2015. This progressive trend is a testament to the country’s commitments to prioritise nutrition issues and nutrition programmes in its development agenda. The Government of Rwanda, through the Ministry of Health, has prioritised malaria control, nutrition education, and better public healthcare. However, in spite of the advancements made, the consensus is that high rates of chronic malnutrition among children still prevail. Thus a better understanding of risk factors that contribute to child malnutrition at the household level in Rwanda was needed to strengthen the fight against malnutrition in the country. The ‘Comprehensive Food Security and Vulnerability and Nutrition Analysis’ – CFSVA 2012 – report produced by the Ministry of Agriculture and Animal Resources (MINAGRI), the National Institute of Statistics of Rwanda (NISR) and the World Food Programme (WFP) acknowledged that vulnerable households are increasingly reliant on markets as a source of food; providing on average 65 percent of the food consumed by a household. It is therefore clear that household nutrition outcomes in such households are dependent on markets. In addition, it is widely accepted that gender dynamics influence decision-making in the household. Thus gender dynamics affect decisions related to food, care, markets, and health. Therefore this survey focused on nutrition, markets, and gender to determine the factors that influence the nutrition status of children under 24 months. Moreover, a disconnect between agricultural production and nutrition outcomes was revealed in the CFSVA 2012 report that indicated that the northern agricultural zones, considered the bread basket of the country, had stunting rates of up to 66 percent in children under 60 months

Survey data on income, food security, and dietary behavior among women and children from households of differing socio-economic status in urban and peri-urban areas of Nairobi, Kenya

This article describes data collected to analyze consumer behaviors in vulnerable populations by examining key access constraints to nutritious foods among households of differing socio-economic status in urban and peri‑urban areas of Nairobi, Kenya. The key variables studied include wealth status, food security, and dietary behavior indicators at individual and household level. Household food insecurity access scale (HFIAS), livelihood coping strategies (LCS), food expenditure share (FES), food consumption score (FCS), household dietary diversity score (HDDS), minimum dietary diversity-women(MDD-W), and child dietary diversity score (CDDS) indicators were used to measure food security. Household assets were used to develop an asset-based wealth index that grouped the study sample population into five wealth quantiles, while income levels were used to estimate FES. The hypothesis that guided the cross-sectional survey conducted to generate these data is that vulnerability to food insecurity and poverty are important drivers of food choice that influence household and individual dietary behavior. Data from this study was thus used to assess direction and strength of association between; household food insecurity, wealth status, women, children, and household dietary behavior in both urban and peri‑urban populations sampled

How big is the potato (Solanum tuberosum L.) yield gap in Sub-Saharan Africa and why? A participatory approach.

According to potato experts from ten Sub-Saharan Africa (SSA) countries working together in a community of practice (CoP) over a 3-years period, potato farmers across SSA can increase their current annual production of 10.8 million metric tons by 140% if they had access to high quality seed along with improved management practices. This paper describes this innovative new methodology tested on potato for the first time, combining modelling and a comprehensive online survey through a CoP. The intent was to overcome the paucity of experimental information required for crop modelling. Researchers, whose data contributed to estimating model parameters, participated in the study using Solanum, a crop model developed by the International Potato Center (CIP). The first finding was that model parameters estimated through participatory modelling using experts’ knowledge were good approximations of those obtained experimentally. The estimated yield gap was 58 Mg ha-1, of which 35 corresponded to a research gap (potential yield minus research yield) and 24 to farmers’ gap (research yield minus farmer’s yield). Over a 6-month period, SurveyMonkey, a Web-based platform was used to assess yield gap drivers. The survey revealed that poor quality seed and bacterial wilt were the main yield gap drivers as perceived by survey respondents

Genetic and Physiological Analysis of Iron Biofortification in Maize Kernels

BACKGROUND: Maize is a major cereal crop widely consumed in developing countries, which have a high prevalence of iron (Fe) deficiency anemia. The major cause of Fe deficiency in these countries is inadequate intake of bioavailable Fe, where poverty is a major factor. Therefore, biofortification of maize by increasing Fe concentration and or bioavailability has great potential to alleviate this deficiency. Maize is also a model system for genomic research and thus allows the opportunity for gene discovery. Here we describe an integrated genetic and physiological analysis of Fe nutrition in maize kernels, to identify loci that influence grain Fe concentration and bioavailability. METHODOLOGY: Quantitative trait locus (QTL) analysis was used to dissect grain Fe concentration (FeGC) and Fe bioavailability (FeGB) from the Intermated B73 × Mo17 (IBM) recombinant inbred (RI) population. FeGC was determined by ion coupled argon plasma emission spectroscopy (ICP). FeGB was determined by an in vitro digestion/Caco-2 cell line bioassay. CONCLUSIONS: Three modest QTL for FeGC were detected, in spite of high heritability. This suggests that FeGC is controlled by many small QTL, which may make it a challenging trait to improve by marker assisted breeding. Ten QTL for FeGB were identified and explained 54% of the variance observed in samples from a single year/location. Three of the largest FeGB QTL were isolated in sister derived lines and their effect was observed in three subsequent seasons in New York. Single season evaluations were also made at six other sites around North America, suggesting the enhancement of FeGB was not specific to our farm site. FeGB was not correlated with FeGC or phytic acid, suggesting that novel regulators of Fe nutrition are responsible for the differences observed. Our results indicate that iron biofortification of maize grain is achievable using specialized phenotyping tools and conventional plant breeding techniques