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Buffering the effect of extreme drought in Zambia: new crops and advisories are helping farmers
No full textThis report assesses the impact of Southern Africa Accelerated Innovation Delivery Initiative (AID-I) Rapid Delivery Hub interventions in mitigating the effects of El Niño-induced drought in Zambia: drought-tolerant maize varieties (DTM), improved legume seeds and an early warning campaign. Approximately 620,000 households (3.1 million people) gained access to DTM seeds through AID-I interventions, cultivating over 230,000 hectares during the 2023/2024 season. Of these, about 462,600 farmers (~27% of smallholder farmers in Zambia) benefited directly from growing DTM, with yield gains averaging 240 kg more maize per hectare (~US 75 and US $58, respectively. At the national level, AID-I supported production for both groundnuts and soybean was 205 tons, representing about 14.3% of national production. Most of those who benefited from improved legume seeds were women. AID-I facilitated the dissemination of an early warning campaign reaching 502,420 farmers with El Niño advisories and established 84 winter production demonstration sites, reaching over 2,000 farmers with alternative cropping strategies. Together, these interventions contributed to enhancing farmers' resilience against the impacts of El Niño-related weather extremes in Zambia.13 page
River pattern influences the composition of small indigenous species (SIS) of fish in deltaic Rajbari district, Bangladesh
No full textBangladesh is endowed with diverse rivers providing huge ecosystem services, but the diversity status and the abundance of the small indigenous species (SIS) are not identical in all rivers due to the natural water flow regime and anthropogenic challenges. Therefore, the present study endeavors to elucidate the composition and conservation status of SIS fish from four rivers namely, the Padma, the Gorai, the Chandana and the Horai rivers of Rajbari District, Bangladesh. Data were meticulously collected through fish sampling in each season, field observations, focus group discussions, and individual interviews by using a semi-structured questionnaire spanning from May 2021 and April 2022. The number of SIS in the Padma, the Gorai, the Chandana and the Horai rivers of Rajbari were 60, 36, 33 and 26, respectively, whereas a predominant concentration of fishes was notably observed in the benthopelagic zone of these rivers. Among the 60 riverine SIS, 23 fish were common in the four rivers. Additionally, Cyprinidae (>30%) was observed to be the most abundant SIS in the studied rivers. The fishermen in the research area used seven major fishing equipment of which cast nets are the most common for catching fish species. The abundance of SIS during the rainy season was the highest for all the studied rivers than the other seasons and 12 SIS were available throughout the year. Notably, the least concerned SIS outnumbered the other categories whereas, more than 10% was under the vulnerable category in the four rivers. The leading threats to the fish diversity were pollution followed by illegal and overfishing, siltation, reduced depth, degeneration of rivers and others. Consequently, to safeguard the existing SIS, reducing human pressure, implementing fishing regulations strictly, establishing and administering fish sanctuaries, and raising public awareness can be helpful for the sustainability of aquatic resources in deltaic areas
Genomic loci associated with grain yield under well-watered and water-stressed conditions in multiple bi-parental maize populations
No full textSmallholder maize farming systems in sub-Saharan Africa (SSA) are vulnerable to drought-induced yield losses, which significantly impact food security and livelihoods within these communities. Mapping and characterizing genomic regions associated with water stress tolerance in tropical maize is essential for future breeding initiatives targeting this region. In this study, three biparental F3 populations composed of 753 families were evaluated in Kenya and Zimbabwe and genotyped with high-density single nucleotide polymorphism (SNP) markers. Quantitative trait loci maping was performed on these genotypes to dissect the genetic architecture for grain yield (GY), plant height (PH), ear height (EH) and anthesis-silking interval (ASI) under well-watered (WW) and water-stressed (WS) conditions. Across the studied maize populations, mean GY exhibited a range of 4.55-8.55 t/ha under WW and 1.29-5.59 t/ha under WS, reflecting a 31-59% reduction range under WS conditions. Genotypic and genotype-by-environment (G x E) variances were significant for all traits except ASI. Overall broad sense heritabilities for GY were low to high (0.25-0.60). For GY, these genetic parameters were decreased under WS conditions. Linkage mapping revealed a significant difference in the number of QTLs detected, with 93 identified under WW conditions and 41 under WS conditions. These QTLs were distributed across all maize chromosomes. For GY, eight and two major effect QTLs (>10% phenotypic variation explained) were detected under WW and WS conditions, respectively. Under WS conditions, Joint Linkage Association Mapping (JLAM) identified several QTLs with minor effects for GY and revealed genomic region overlaps in the studied populations. Across the studied water regimes, five-fold cross-validation showed moderate to high prediction accuracies (-0.15-0.90) for GY and other agronomic traits. Our findings demonstrate the polygenic nature of WS tolerance and highlights the immense potential of using genomic selection in improving genetic gain in maize breeding
Breeding process and Capacity improvement during 2024 in KALRO dryland crops breeding programs
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Situation report on Nepal’s agrifood systems: January 2024
No full textFrom mid-November to December 2023, Nepal witnessed the lowest Consumer Price Inflation (CPI) in 12 months. The average year-on-year CPI registered a decline of 4.9 percent, which was primarily propelled by a 3.1 percent fall in food and beverage prices. This decline will have positive implications on poor rural and urban households allowing them to access and afford more food and nutrients.11 page
Workshop Report and Synthesis. Plausible impact pathways for dryland crops: reaching the hard-to-reach
No full text49 page
Genomic prediction of the performance of tropical doubled haploid maize lines under artificial Striga hermonthica (Del.) Benth. infestation
No full textStriga hermonthica (Del.) Benth., a parasitic weed, causes substantial yield losses in maize production in sub-Saharan Africa. Breeding for Striga resistance in maize is constrained by limited genetic diversity for Striga resistance within the elite germplasm and phenotyping capacity under artificial Striga infestation. Genomics-enabled approaches have the potential to accelerate identification of Striga resistant lines for hybrid development. The objectives of this study were to evaluate the accuracy of genomic selection for traits associated with Striga resistance and grain yield (GY) and to predict genetic values of tested and untested doubled haploid maize lines. We genotyped 606 doubled haploid lines with 8,439 rAmpSeq markers. A training set of 116 doubled haploid lines crossed to 2 testers was phenotyped under artificial Striga infestation at 3 locations in Kenya. Heritability for Striga resistance parameters ranged from 0.38-0.65 while that for GY was 0.54. The prediction accuracies for Striga resistance-associated traits across locations, as determined by cross-validation (CV) were 0.24-0.53 for CV0 and from 0.20 to 0.37 for CV2. For GY, the prediction accuracies were 0.59 and 0.56 for CV0 and CV2, respectively. The results revealed 300 doubled haploid lines with desirable genomic estimated breeding values for reduced number of emerged Striga plants (STR) at 8, 10, and 12 weeks after planting. The genomic estimated breeding values of doubled haploid lines for Striga resistance-associated traits in the training and testing sets were similar in magnitude. These results highlight the potential application of genomic selection in breeding for Striga resistance in maize. The integration of genomic-assisted strategies and doubled haploid technology for line development coupled with forward breeding for major adaptive traits will enhance genetic gains in breeding for Striga resistance in maize
Efficient arabinoxylan assay for wheat: Exploring variability and molecular marker associations in Wholemeal and refined flour
No full textIn this study, we present a modified high throughput phloroglucinol colorimetric assay for the quantification of arabinoxylans (AX) in wheat named PentoQuant. The method was downscaled from a 10 ml glass tube to 2 ml microcentrifuge tube format, resulting in a fivefold increase in throughput while concurrently reducing the overall cost and manual labor required for the analysis. Comparison with established colorimetric assays and gas chromatography validates the modified protocol, demonstrating its superior repeatability, rapidity, and simplicity. The effectiveness of the protocol was tested on 606 unique whole meal (WM) and refined flour (RF) bread wheat samples which revealed the presence of more than a twofold variation in both the soluble (WE-AX) and total (TOT-AX) AX fractions in WM (TOT-AX = 31.9–76.1 mg/g; WE-AX = 4.4–12.6 mg/g) and RF (TOT-AX = 7.7–22.4 mg/g; WE-AX = 3.9–11.4 mg/g). Results obtained from the AX quantification were used to test the effectiveness of four molecular markers associated with AX variation and targeting two major genomic regions on the 1BL and 6BS chromosomes. These markers appeared to be particularly relevant for the WE-AX fraction, providing insights to enable marker-assisted breeding
