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Detecting and quantifying zero tillage technology adoption in Indian smallholder systems using Sentinel-2 multi-spectral imagery
No full textZero tillage (ZT), an important component of Conservation Agriculture, has enormous potential to curb emissions from residue burning, increase soil organic carbon and water retention, reduce land preparation costs and increase the long-term productivity and profitability of the farming system. Despite the promise of ZT, little is known about how widely it has been adopted at regional scales in smallholder systems, where management is heterogeneous. Identifying ZT diffusion patterns across space and time along with other popular tillage technologies, such as conventional tillage (CT) and shallow tillage (ST), helps to target and disseminate the most effective technologies and estimate their climate change mitigation potential. Acknowledging the complexities involved in distinguishing ZT from CT and ST in smallholder fields, this study utilized an innovative two-step change detection method leveraging early-season Sentinel-2 multi-spectral imagery. We developed and applied our model in the Indian state of Punjab over three years (2020-2022). Our method outperformed traditional binary classification models, achieving 81 % accuracy. The analysis indicated that areas under different tillage types changed over time across Punjab. Specifically, from 2020 to 2021, we found a 33 % and 4 % decrease in ZT and CT, respectively. However, a 29 % increase is observed in CT adoption. On the other hand, from 2021 to 2022, the adoption rates for ZT and CT increased by 18 % and 2 %, respectively, while ST adoption decreased by 12 %. Overall, this study demonstrates the potential use of early season Sentinel-2 imagery to map the adoption of tillage practices in smallholder systems. Our approach can provide large-scale information on technology uptake, aiding policies to implement carbon markets and the scaling up of sustainable agricultural practices in India
Dissecting the effect of heat stress on durum wheat under field conditions
No full textIntroduction Heat stress negatively affects wheat production in several ways, mainly by reducing growth rate, photosynthetic capacity and reducing spike fertility. Modeling stress response means analyzing simultaneous relationships among traits affecting the whole plant response and determinants of grain yield. The aim of this study was to dissect the diverse impacts of heat stress on key yield traits and to identify the most promising sources of alleles for heat tolerance.Methods We evaluated a diverse durum wheat panel of 183 cultivars and breeding lines from worldwide, for their response to long-term heat stress under field conditions (HS) with respect to non stress conditions (NS), considering phenological traits, grain yield (GY) and its components as a function of the timing of heat stress and climatic covariates. We investigated the relationships among plant and environmental variables by means of a structural equation model (SEM) and Genetic SEM (GSEM).Results Over two years of experiments at CENEB, CIMMYT, the effects of HS were particularly pronounced for the normalized difference vegetation index, NDVI (-51.3%), kernel weight per spike, KWS (-40.5%), grain filling period, GFP (-38.7%), and GY (-56.6%). Average temperatures around anthesis were negatively correlated with GY, thousand kernel weight TKW and test weight TWT, but also with spike density, a trait determined before heading/anthesis. Under HS, the correlation between the three major determinants of GY, i.e., fertile spike density, spike fertility and kernel size, were of noticeable magnitude. NDVI measured at medium milk-soft dough stage under HS was correlated with both spike fertility and grain weight while under NS it was less predictive of grain weight but still highly correlated with spike fertility. GSEM modeling suggested that the causal model of performance under HS directly involves genetic effects on GY, NDVI, KWS and HD.Discussion We identified consistently suitable sources of genetic resistance to heat stress to be used in different durum wheat pre-breeding programs. Among those, Desert Durums and CIMMYT'80 germplasm showed the highest degree of adaptation and capacity to yield under high temperatures and can be considered as a valuable source of alleles for adaptation to breed new HS resilient cultivars
Risk-based evaluations of competing agronomic climate adaptation strategies: The case of rice planting strategies in the indo-Gangetic Plains
No full textCONTEXT: Adjusting crop planting dates and variety durations is emerging as a crucial climate change adaptation strategy for many cereal systems. Such strategies include harmonizing crop planting with the onset of the rainy season or planting at specific recommended calendar dates. Evaluations of these strategies mostly consider yield and yield variability, but focus less on financial risks associated with different planting strategies and importance of risk aversion behaviour of the farmers in their decision to adopt the strategies. OBJECTIVE: Here, we present a novel framework that uses a computational spatial ex-ante approach for risk-based evaluations of agronomic adaptation options. This framework allows development agronomic adaptation recommendations that consider climate risks for risk-averse famrers. METHODS: We use a second order stochastic dominance approach that is paired with computational optimization—Golden section search algorithm. This approach allows a distributional assessment of risk and uncertainty by providing bounds at which even a risk averse would benefit from changing practices. This contrasts with conventional methods that do not consider farmers' risk aversion, e.g. mean-variance or conditional value at risk optimization methods. To demonstrate our approach, we compare the yield risks and economic risks associated with readily available gridded crop simulation outputs for various rice planting strategies across the Indo-Gangetic Plains (IGP)– a major region experiencing food insecurity and climate impacts. RESULTS AND CONCLUSIONS: The findings provide quantitative evidence about the riskiness of previously recommended rice planting date strategies. The risk-based assessment corroborates the recommendation for planting long-duration varieties at the monsoon onset with or without supplemental irrigation (covering about 22% of IGP area) in the Eastern IGP, and at state-recommended planting dates (covering about 38% of IGP area) in most of the Western and Middle IGP. Importantly, our risk-based assessment shows where the results are not as clear cut and which strategy is the least risky. This is especially important in the Middle IGP where farmers appear to have more flexibility to achieve comparable outcomes with several planting strategies. SIGNIFICANCE: In conclusion, the proposed approach provides a useful and novel tool for comparing different agronomic climate adaptation strategies from an economic risk perspective in a spatial framework
Design and comparison of two maize seeders coupled with an agricultural robot
No full textIn recent years, the development of robotic vehicles in agriculture has made it possible to reduce human intervention and fatigue in carrying out arduous or repetitive tasks, as well as helping to promote sustainable agriculture to address climate change. However, the great diversity of agricultural tasks and the varied production systems and crops demand a wide range of solutions that can be adapted to robotic vehicles as a power source. These alternatives must be affordable and user-friendly for some users, although more sophisticated solutions must also be developed for others, depending on their specific needs. For this, the present work focuses on the development of two maize seeders with different metering systems coupled to an agricultural robot. The first seeder has a conventional mechanically driven seed metering system with a drive wheel and chain gear, while the second one has an electronically driven metering system based on a DC motor and a digital encoder controlled by a microcontroller. Both seeders were coupled to a remote-controlled robotic vehicle and evaluated on real farmland. Seed distribution in the seed rows was contrasting; the results indicated that the mechanical system performed better in the field than the electronic system. For both seeders, the working capacity was approximately 0.135 ha/h at an average speed of 2.0 km/h. The proposed robot–seeder assembly could help farmers automate and reduce the workload associated with planting, as well as attract young people to the field
Noroeste C2021: New durum wheat variety for Northwestern Mexico
No full textEn México, durante el año 2021 se cosecharon 511,059.82 ha de trigo (Triticum spp.) con una producción de 3,224,931 t. En el estado de Sonora en ese mismo ciclo se cosecharon 236,467.08 ha con una producción de 1,721,608 t, lo que constituyó el 53.38 % de la producción nacional (SIAP, 2022). Un año después, en dicha entidad se sembraron 283,155.27 ha, de las cuales 222,986.63 se cultivaron con la variedad de trigo duro CIRNO C2008, lo que representó 78 % de la superficie (CESAVESON, 2022). Al ser una variedad susceptible al hongo Puccinia triticina E., causante de la roya de la hoja (Huerta-Espino et al., 2017), requiere de una a dos aplicaciones de fungicidas durante el ciclo, lo que representa un gasto adicional en los costos de producción y un impacto ambiental negativo en la región. A pesar de la perdida de la resistencia, los productores no dejan de cultivarla por su tolerancia al acame con altas densidades de siembra. Otra limitante en la producción de trigo en el noroeste de México es la disponibilidad de agua, la captación de agua en los sistemas de presas de Sonora y Sinaloa ha sido baja en los últimos años, la cantidad de agua disponible para la siembra se redujo considerablemente. En Sonora, la captación de agua se redujo de 3,041.3 millones de metros cúbicos (Mm3) a 1,058.3 Mm3 durante el ciclo agrícola 2022-2023 (DRRY, 2024), lo anterior ocasionó que los riegos de auxilio se redujeran de 4 a 2 y 3 riegos en el Valle del Mayo y del Yaqui, respectivamente.417-42
Understanding crop diversification among smallholder farmers: Socioeconomic insights from central Malawi
No full textIn Eastern and Southern Africa (ESA), smallholder rain-fed systems are vital, yet they are challenged by land degradation, soil fertility decline, and climate risks. To address these challenges, crop diversification has been promoted as a potential pathway to enhance productivity, improve nutritional security, and offer a viable pathway out of poverty and hunger. This study explores crop diversification among 150 smallholder households in the Kasungu, Mchinji, and Lilongwe districts of Malawi, where the project Sustainable Intensification of Maize Legume Systems in East and Southern Africa (SIMLESA) has engaged the smallholder farmers in conservation agriculture (CA)-based sustainable intensification participatory research and development for seven years since 2010. This study used Simpson’s diversity index (SDI) to estimate crop diversification, and a multiple linear regression model (MLRM) to analyze how smallholder farmers’ socio-economic characteristics influence adoption. The findings show a prevalence of small farms of less than 1.5 hectares, with most farmers perceiving crop diversification as beneficial for soil fertility. Key adoption constraints include labor shortages and a lack of legume seeds. SIMLESA participants lead in crop rotations, with a 63% higher adoption rate, and show the highest crop diversity, with a 99% increase in farmers growing three crops and a 74% increase in those growing four crops compared to non-SIMLESA farmers. The SDI values were 0.39 for non-SIMLESA, 0.48 for SIMLESA neighbors, and 0.57 for SIMLESA participants. Access to NGO inputs, larger farm sizes, and participation in research programs were positively associated with diversification, while food insufficiency was negatively associated with its adoption. The study highlights the importance of integrating participatory research methods to promote development initiatives effectively
Characterization of a 4.1 Mb inversion harboring the stripe rust resistance gene YR86 on wheat chromosome 2AL
No full textWheat cultivar Zhongmai 895 was earlier found to carry YR86 in an 11.6 Mb recombination-suppressed region on chromosome 2AL when crossed with Yangmai 16. To fine-map the YR86 locus, we developed two large F2 populations from crosses Emai 580/Zhongmai 895 and Avocet S/Zhongmai 895. Remarkably, both populations exhibited suppressed recombination in the same 2AL region. Collinearity analysis across Chinese Spring, Aikang 58, and 10+ wheat genomes revealed a 4.1 Mb chromosomal inversion spanning 708.5–712.6 Mb in the Chinese Spring reference genome. Molecular markers were developed in the breakpoint and were used to assess a wheat cultivar panel, revealing that Chinese Spring, Zhongmai 895, and Jimai 22 shared a common sequence named InvCS, whereas Aikang 58, Yangmai 16, Emai 580, and Avocet S shared the sequence named InvAK58. The inverted configuration explained the suppressed recombination observed in all three bi-parental populations. Normal recombination was observed in a Jimai 22/Zhongmai 895 F2 population, facilitating mapping of YR86 to a genetic interval of 0.15 cM corresponding to 710.27–712.56 Mb falling within the inverted region. Thirty-three high-confidence genes were annotated in the interval using the Chinese Spring reference genome, with six identified as potential candidates for YR86 based on genome and transcriptome analyses. These results will accelerate map-based cloning of YR86 and its deployment in wheat breeding.1168-117
Menú tecnológico - Maiz y frijol en el Occidente de Guatemala
No full textEn la región occidente de Guatemala la agricultura de subsistencia normalmente se realiza en laderas que incluye prácticas agronómicas manuales que contribuyen a la degradación de los suelos (quema, movimiento de suelo con azadón, siembras a favor de la pendiente) incrementando la vulnerabilidad en este sistema productivo. Aunque el sector agrícola es vulnerable, también hay oportunidades para generar nuevos modelos de producción que ayuden a adaptarse y a mitigar efectos del cambio climático, por lo que se hace necesario trabajar en sistemas de investigación aplicada que permita a los productores guatemaltecos implementar nuevas prácticas y/o tecnologías que contribuyan a la sostenibilidad de los sistemas agroalimentarios. A través de las acciones de la iniciativa AgriLAC Resiliente y ASOCUCH (Asociación de Organizaciones de los Cuchumatanes) en 2023 se instaló la plataforma Aguacatán, Huehuetenango donde se realizó investigación agronómica a partir de las áreas de oportunidad en el sistema de producción del innovahub Occidente. La investigación que se desarrolla en la plataforma Aguacatán, Huehuetenango y por otras instituciones como ICTA, se ha generado el siguiente menú tecnológico con el objetivo de brindar una herramienta para la toma de decisiones informadas por parte de técnico y grupos de productores. Las tecnologías que no están incluidas en el menú tecnológico no han sido evaluadas de manera científica o práctica en el innovahub Occidente, Guatemala.11 page
The formal seed system of maize in Ethiopia: Implications for reducing the yield gap
No full textSmallholder farmers' access to and use of quality seeds of improved varieties and hybrids is an integral component of sustainable maize production and the reduction of the yield gap in Ethiopia. Formal seed supply systems play a pivotal role in ensuring farmers' access to good quality seed and increasing the productivity of maize. However, the contribution of the formal seed system to the increase in the average national maize yield in the country is not well documented. This paper specifically analyzes the formal seed supply systems and contributions of improved seed to maize productivity increase in Ethiopia. Secondary sources of information, including published and unpublished data, were used. Analysis of the seed value chain from research to commercial seed producers indicated that public and private maize hybrids dominate the formal seed system. Increased use of improved seed and associated management practices has contributed to the yield increase at the national level. For every 10,000 MT of additional maize-improved seed used by smallholder farmers, the national average maize yield increased by 400 kg per hectare (R sq. = 0.59). Hence, in addition to other yield-increasing technologies and extension support, ensuring the availability of improved seed to farmers can significantly contribute to reducing the maize yield gap between the national average yield and the average yield from on-farm demonstrations already attained by farmers in Ethiopia. Various policy interventions are suggested to improve the maize seed system performance and increase the supply of maize improved seeds