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Conservation agriculture enhances maize yields and profitability in Mexico's semi-arid highlands
No full textRainfed agriculture in semi-arid regions is affected by variable rainfall patterns, resulting in low yields under conventional farming systems. To address this issue, cropping systems based on conservation agriculture were evaluated in 2 field experiments on 17 farmers' fields in the semi-arid highlands of Queretaro, Mexico, from 2013 to 2020, to assess yields and profitability. Monocropped maize (Zea mays L.) under conventional tillage was compared to growing maize on permanent beds with soil mulch, either monocropped or in rotation with triticale (X Triticum Secale Wittmack), oats (Avena sativa L.), or common beans (Phaseolus vulgaris L.). In the San Juan del Rio field experiment, maize yields on permanent beds averaged from 2,475 to 3,517 kg ha- 1 over five years, exceeding 70% the yields under conventional tillage. In the Cadereyta field experiment, 4-year average maize yields on permanent beds ranged from 979 to 1,382 kg ha- 1 with no significant difference to those under conventional tillage. In farmers' fields, maize on permanent beds yielded an average of 3,717 kg ha- 1, 70% higher than with conventional tillage. The most profitable system was permanent beds with a maize-bean rotation in field experiments and with maize monocropping in farmers' fields. Overall, conservation agriculture can improve maize yields and profitability in Central Mexico's semi-arid highlands
Enabling Agrifood Systems Transformation in South Asia with Data and Evidence: Opportunities and Challenges (Webinar session 10)
No full textSouth Asia, home to one quarter of the global population, faces issues such as poverty, malnutrition, and unsustainable food production systems despite being a major producer of food. The region faces escalating levels of unhealthy food consumption, unsustainable farming practices, and the adverse impacts of climate change. TAFSSA (Transforming Agrifood Systems in South Asia), a CGIAR Regional Integrated Initiative, seeks to deliver actionable evidence and scalable innovations in Bangladesh, India, and Nepal.Timothy J. KrupnikAvinash KishoreSamuel ScottPrakashan Chellatton VeettiSherya ChakrabortyPurnima MenonAruna PalikheSabrina RasheedZahidul Hassan1:32:1
Projecting the contribution of provitamin A maize biofortification and other nutrition interventions to the nutritional adequacy and cost of diets in rural Zimbabwe
No full textBackground: Evidence of the effectiveness of biofortified maize with higher provitamin A (PVA) to address vitamin A deficiency in rural Africa remains scant. Objectives: This study projects the impact of adopting PVA maize for a diversity of households in an area typical of rural Zimbabwe and models the cost and composition of diets adequate in vitamin A. Methods: Household-level weighed food records were generated from 30 rural households during a week in April and November 2021. Weekly household intakes were calculated, as well as indicative costs of diets using data from market surveys. The impact of PVA maize adoption was modeled assuming all maize products contained observed vitamin A concentrations. The composition and cost of the least expensive indicative diets adequate in vitamin A were calculated using linear programming. Results: Very few households would reach adequate intake of vitamin A with the consumption of PVA maize. However, from a current situation of 33%, 50%–70% of households were projected to reach ≤50% of their requirements (the target of PVA), even with the modest vitamin A concentrations achieved on-farm (mean of 28.3 μg RAE per 100 g). This proportion would increase if higher concentrations recorded on-station were achieved. The estimated daily costs of current diets (mean ± standard deviation) were USD 1.43 ± 0.59 in the wet season and USD 0.96 ± 0.40 in the dry season. By comparison, optimization models suggest that diets adequate in vitamin A could be achieved at daily costs of USD 0.97 and USD 0.79 in the wet and dry seasons, respectively. Conclusions: The adoption of PVA maize would bring a substantial improvement in vitamin A intake in rural Zimbabwe but should be combined with other interventions (e.g., diet diversification) to fully address vitamin A deficiency.1815-182
Use of remote sensing for linkage mapping and genomic prediction for common rust resistance in maize
No full textBreeding for disease resistance is a central component of strategies implemented to mitigate biotic stress impacts on crop yield. Conventionally, genotypes of a plant population are evaluated through a labor-intensive process of assigning visual scores (VS) of susceptibility (or resistance) by specifically trained staff, which limits manageable volumes and repeatability of evaluation trials. Remote sensing (RS) tools have the potential to streamline phenotyping processes and to deliver more standardized results at higher through-put. Here, we use a two-year evaluation trial of three newly developed biparental populations of maize doubled haploid lines (DH) to compare the results of genomic analyses of resistance to common rust (CR) when phenotyping is either based on conventional VS or on RS-derived (vegetation) indices. As a general observation, for each population × year combination, the broad sense heritability of VS was greater than or very close to the maximum heritability across all RS indices. Moreover, results of linkage mapping as well as of genomic prediction (GP), suggest that VS data was of a higher quality, indicated by higher −logp values in the linkage studies and higher predictive abilities for genomic prediction. Nevertheless, despite the qualitative differences between the phenotyping methods, each successfully identified the same genomic region on chromosome 10 as being associated with disease resistance. This region is likely related to the known CR resistance locus Rp1. Our results indicate that RS technology can be used to streamline genetic evaluation processes for foliar disease resistance in maize. In particular, RS can potentially reduce costs of phenotypic evaluations and increase trialing capacities
Advances in sorghum improvement for climate resilience in the global arid and semi-arid tropics: A Review
No full textSorghum is a climate-resilient crop which has been cultivated as a staple food in the semi-arid areas of Africa and Asia for food and nutrition security. However, the current climate change is increasingly affecting sorghum performance, especially at the flowering stage when water availability is critical for grain filling, thus lowering the sorghum grain yield. The development of climate-resilient, biotic and abiotic stress-tolerant, market-preferred, and nutrient-dense sorghum varieties offers a potentially cost-effective and environmentally sustainable strategy for adapting to climate change. Some of the common technologies for sorghum improvement include mass selection, single seed descent, pure line selection, and marker-assisted selection, facilitated by backcrossing and genotyping using molecular markers. In addition, recent advancements including new machine learning algorithms, gene editing, genomic selection, rapid generation advancement, and recycling of elite material, along with high-throughput phenotyping tools such as drone- and satellite-based images and other speed-breeding techniques, have increased the precision, speed, and accuracy of new crop variety development. In addition to these modern breeding tools and technologies, enhancing genetic diversity to incorporate various climate resilience traits, including against heat and drought stress, into the current sorghum breeding pools is critical. This review covers the potential of sorghum as a staple food crop, explores the genetic diversity of sorghum, discusses the challenges facing sorghum breeding, highlights the recent advancements in technologies for sorghum breeding, and addresses the perceptions of farmers on sorghum production under the current climate change conditions
Exploring underlying drivers and factors, and the impact of social networks on farmers' use of integrated pest management strategies in Bangladesh
No full textThis report presents findings from a research study conducted under the Bangladesh Integrated Pest Management Activity (IPMA) involving 2,250 respondents, including 2,000 farmers, 100 dealers/retailers, 100 local service providers (LSPs) or pesticide sprayers, and 50 Sub-Assistant Agriculture Officers (SAAOs) across ten districts in Bangladesh. The study examined pest management strategies among farmers, both IPM users and non-users, focusing on decision-making processes, factors influencing IPM usage in five key crops—rice, maize, tomato, mungbean, and mango—and the role of stakeholders and social networks in pesticide selection and use.20 page
Morphological and biochemical changes in the mediterranean cereal cyst nematode (Heterodera latipons) during diapause
No full textThe cereal cyst nematode (Heterodera latipons) is becoming an economically important species in global cereal production as it is being identified in many new cereal cultivated areas and causes significant losses. Consequently, understanding its biology becomes crucial for researchers in identifying its vulnerabilities and implementing effective control measures. In the current study, different morphological and biochemical changes of H. latipons cysts containing eggs with infective juveniles from a barley field in Jordan were studied during the summer of 2021, at two sample dates. The first, at the harvest of the cereal crop (June 2021), when the infective second-stage juveniles (J2s) were initiating diapause, and the second, before planting the sequent cereal crop (late October 2021), when the J2s were ending diapause. The studied population was characterized morphologically and molecularly, showing 98.4% molecular similarity to both JOD from Jordan and Syrian "300" isolates of H. latipons. The obtained results and observations revealed that there were dramatic changes in all the investigated features of the cysts and eggs they contained. Morphological changes such as cyst color, sub-crystalline layer, and thickness of the rigid eggshell wall were observed. A slight change in the emergence time of J2s from cysts was observed without any difference in the number of emerged J2s. The results of biochemical changes showed that the total contents of carbohydrates, glycogen, trehalose, glycerol, and protein were higher in cysts collected in October when compared to those cysts collected in June. The SDS-PAGE pattern indicated the presence of a protein with the size of ca. 100 kDa in both sampling dates, whereas another protein (ca. 20 kDa) was present only in the cysts of October. Furthermore, the expression of trehalase (tre) gene was detected only in H. latipons collected in October. The outcomes of this study provide new helpful information that elucidates diapause in H. latipons and may be used for the implementation of new management strategies of cyst nematodes
Technology adoption and weed emergence dynamics: social ecological modeling for maize-legume systems across Africa
No full textEcological practices such as intercropping maize (Zea mays) with cowpea (Vigna unguiculata L.) have been promoted to combat parasitic weeds like Striga (Striga asiatica). Intercropping has been promoted across Africa as a Striga control practice (SCP) and food security measure. Despite past efforts, millions of smallholder farmers (cultivating < 2 ha of maize) still struggle to implement SCPs. Social and ecological factors that prevent SCP implementation are well documented in the literature, but their underlying interactions have remained elusive. System dynamics modeling can uncover these interactions and assess their effect on intercropping rates as well as Striga emergence. This study presents a participatory mixed methods approach to build a system dynamics model based on two theories: diffusion of innovations and resource pool dynamics. The model estimates the population of fields where Striga emerged in response to intercropped fields when various interventions were implemented. According to model simulations, if new policies are not enacted to support intercropping, Striga is likely to spread to 2,625,000 maize fields, parasitizing almost 75% of smallholder farms across Central Malawi by 2036. The participatory approach allowed us to evaluate several policies, one of which sustained enough adopters to limit Striga emergence to < 500,000 fields, reducing the weed’s threat to food security. This policy considers how input costs and erratic rainfall can lead to disadoption, therefore, supporting the implementation of five to six consecutive years of intercropping by providing both fertilizer subsidies and demonstration plots. In this study, our participatory approach has shown to develop a model that can highlight interactions in social ecological systems, their leverage points, and how they can be exploited to develop effective food security policies
