Soil fertility provides the foundation for nutritious food production and resilient and sustainable livelihoods. A comprehensive survey and summit meeting were conducted with the aims of understanding barriers to enhancing soil fertility in sub-Saharan Africa and providing evidence-based recommendations. The focus regions were West Africa, East Africa, the Great Lakes region, and Ethiopia. Overall recommendations were developed with four emerging themes: (1) strengthening inorganic fertilizer-based systems, (2) access to and use of quality organic inputs, (3) capacity building along the entire knowledge-transfer value chain, and (4) strengthening farming systems research and development across biophysical and socio-economic factors. The evidence-based process and methodology for prioritizing these recommendations makes these findings useful for setting out action plans for future investments and strategies. Access to inorganic fertilizer, its use, and related implementation issues were prominent considerations; nevertheless, biophysical and socio-economic barriers and solutions were identified as equally important to building soil fertility and natural resources. Soil management initiatives should focus on providing holistic solutions covering both biophysical and socio-economic aspects along the entire value chain of actors and creating an enabling environment for adoption. A broader view of soil fertility improvement using all available options including both inorganic and organic sources of nutrients and farming system approaches are highly recommended.

Attractive toxic sugar bait (ATSB) sprayed onto vegetation has been successful in controlling Anopheles mosquitoes outdoors. Indoor application of ATSB has yet to be explored. The purpose of this study was to determine whether ATSB stations positioned indoors have the potential to kill host-seeking mosquitoes and constitute a new approach to control of mosquito-borne diseases. Insecticides were mixed with dyed sugar solution and tested as toxic baits against Anopheles arabiensis, An. Gambiae s.s. and Culex quinquefasciatus in feeding bioassay tests to identify suitable attractant-insecticide combinations. The most promising ATSB candidates were then trialed in experimental huts in Moshi, Tanzania. ATSB stations were hung in huts next to untreated mosquito nets occupied by human volunteers. The proportions of mosquitoes killed in huts with ATSB treatments relative to huts with non-insecticide control treatments huts were recorded, noting evidence of dye in mosquito abdomens. In feeding bioassays, chlorfenapyr 0.5% v/v, boric acid 2% w/v, and tolfenpyrad 1% v/v, mixed in a guava juice-based bait, each killed more than 90% of pyrethroid-susceptible An. Gambiae s.s. and pyrethroid-resistant An. arabiensis and Cx. quinquefasciatus. In the hut trial, mortality rates of the three ATSB treatments ranged from 41-48% against An. arabiensis and 36-43% against Cx. quinquefasciatus and all were significantly greater than the control mortalities: 18% for An. arabiensis, 7% for Cx. quinquefasciatus (p<0.05). Mortality rates with ATSB were comparable to those with long lasting insecticidal nets previously tested against the same species in this area. Indoor ATSB shows promise as a supplement to mosquito nets for controlling mosquitoes. Indoor ATSB constitute a novel application method for insecticide classes that act as stomach poisons and have not hitherto been exploited for mosquito control. Combined with LLIN, indoor use of ATSB has the potential to serve as a strategy for managing insecticide resistance.

A regional geopolitical conflict and sudden massive supply disruptions have revealed vulnerabilities in our global fuel–fertilizer–food nexus. As nitrogen (N) fertilizer price spikes threaten food security, differentiated responses are required to maintain staple cereal yields across over- and underfertilized agricultural systems. Through integrated management of organic and inorganic N sources in high- to low-input cereal production systems, we estimate potential total N-fertilizer savings of 11% in India, 49% in Ethiopia and 44% in Malawi. Shifting to more cost-effective, high-N fertilizer (such as urea), combined with compost and integration of legumes, can optimize N in N-deficient systems. Better targeted and more efficient N-fertilizer use will benefit systems with surplus N. Geospatially differentiated fertilization strategies should prioritize high-N fertilizer supply to low-yield, N-deficient locations and balanced fertilization of N, P, K and micronutrients in high-yield systems. Nationally, governments can invest in extension and realign subsidies to enable and incentivize improved N management at the farm level.

Heat stress is one of the production constraints for tomato (Solanum lycopersicum L.) due to unfavorable, above optimum temperatures. This research was undertaken to evaluate growth and fruit yield of tomato genotypes under three contrasting growing conditions (i.e., optimal temperature in field-, high temperature in field- and high temperature in greenhouse conditions) to determine their relative heat tolerance. Eleven tomato genotypes, including two local check varieties, were evaluated, and data on growth and yield were measured and analyzed. The interactions between the genotypes and growing conditions for all yield traits were significant. In general, the performance of tomato under optimal temperature field conditions was better than under high temperature field- and greenhouse conditions. Genotypes CLN1621L, CLN2026D, CLN3212C, and KK1 had consistently greater fruit yield per plant in all growing conditions. Although the local genotype, Neang Tamm, had lower yield under optimal conditions, it performed moderately well under high temperature field- and high temperature greenhouse conditions, and yield decrease under high temperature condition was minimal. Genotype CLN1621L had stable fruit setting compared to other genotypes under high temperature conditions. Since fruit setting and yield are important traits for heat tolerance, genotypes CLN1621L and Neang Tamm are potential candidates for breeding programs focused on improved yield and heat stress tolerance.

Timing of micronutrient demand and acquisition by maize (Zea mays L.) is nutrient specific and associated with key vegetative and reproductive growth stages. The objective of this study was to determine the fate of foliar-applied B, Fe, Mn, Zn, and Fe/Zn together, evaluate the effect of foliar micronutrients applied at multiple rates and growth stages on maize grain yield, and determine their apparent nutrient recovery efficiency (ANR). Five Randomized Complete Block Design (RCBD) experiments were conducted in 2014 and 2015 at five locations across Nebraska. Total dry matter was collected at 5–6 stages, and separated into leaves, stalk, and reproductive tissue as appropriate to determine micronutrient uptake, partitioning, and translocation. Foliar B, Mn, Zn, and Fe/Zn had no effect on grain yield for most application time by rate levels, though, at the foliar Mn site, there was a 19% yield increase due to a V18 application of 0.73 kg Mn ha⁻¹ which corresponded with reduced Mn uptake in maize grown in control plots. At the foliar Zn site, there was 4.5% decrease in yield due to a split foliar application of 0.84 kg Zn ha⁻¹ total, applied at V11 and V15 stage, which increased leaf Zn concentrations greater than the established toxic level. Only the Fe site had consistent grain yield response and was the only experiment that had visual signs of micronutrient deficiency. Regardless of application time from V6 to R2, there was a 13.5–14.6% increase in grain yield due to 0.22 kg Fe ha⁻¹ foliar application. Most micronutrients had limited or no translocation, however, early season applications of B, prior to V10, had significant mobilization to reproductive tissues at or after VT. Foliar Mn, Zn, and B application had ANR LSmeans of 9.5, 16.9, and 2.5%, respectively, whereas the Fe/Zn mix had negative ANR LSmeans of −9.1% Fe and −1.3% Zn which indicate suppression. These data highlight the importance of confirming a micronutrient deficiency prior to foliar application, guide specific growth stages to target with specific micronutrients, track the fate of foliar-applied micronutrients, and describe the variable effect of foliar-applied micronutrients on grain yield.

Resilience of smallholder farmers in their ability to bounce-back and overcome shocks, such as drought, is critical to ensure a pathway out of hunger and poverty. Efficient water conservation methods that increase rainwater capture and reduce soil erosion such as stone lines and grass bands are two technologies that have been proposed to increase the resilience in Sudano–Sahelian farming systems. In Burkina Faso, we show that stone lines, grass bands, and crop rotation are effective resilience strategies individually and in combination. During years when rainfall is well-distributed over time, differences are minimal between fields with water conservation methods and fields without. However, when there are periods of prolonged drought, water conservation methods are effective for increasing soil water, yield, revenue, and resilience. During drought conditions, sorghum (Sorghum bicolor (L.) Moench) grain yield and revenue with stone lines and grass bands were over 50% greater than that of the control, by an average of 450 kg ha⁻¹, which amounted to an increase of 58,500 West African CFA franc (CFA) ha⁻¹ (i.e., 98 USD ha⁻¹). The results also suggest that the combination of water conservation method and crop rotation additionally improves cropping system productivity and revenue. Growing cowpea (Vigna unguiculata (L.) Walp.) in rotation with sorghum production provided more options for farmers to increase their income and access to nutrition. This study also sheds light on the limited productivity gains due to improved crop varieties. The local sorghum landrace, Nongomsoba, and the local cowpea variety in rotation resulted in the highest yields as compared to the improved varieties of Sariaso 14 sorghum and KVX 396-4-4 cowpea. Under similar low input/degraded conditions, improved crop varieties likely are not a suitable resilience strategy alone. We conclude that during erratic rainy seasons with frequent periods of drought (i.e., water stress) in rain-fed conditions in Burkina Faso, stone lines or grass bands in combination with sorghum and cowpea rotation are effective practices for increasing resilience of smallholder farmers to maintain crop productivity and revenue. With future and present increases in climate variability due to climate change, stone lines, grass bands, and crop rotation will have growing importance as resilience strategies to buffer crop productivity and revenue during periods of drought.