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Estimating crop coefficients for vegetable production and agricultural water management under climate change in sub-humid tropics
Author(s): Tegegne, Desalegn; Schmitter, Pera; Abeyou, Abeyou; Lefore, Nicole (Frontiers Media)
Date: 2025-03-06
Type: Journal Article
Status: Open access
Understanding current and future crop water demand is crucial for improving agricultural productivity and managing long-term water resources in a changing climate. This study aimed to estimate how the crop water demand will change under different water management practices and climate change scenarios. The field experiment using irrigation decision-making tools was carried out in 2016 and 2017 in Lemo, Ethiopia. Crop and water management data were collected on cabbage and carrot production. The field data were used to estimate the crop coefficient (Kc), and the results were compared with the simulated Kc with the Agricultural Policy Environmental eXtender (APEX) model. Predicted future climate data were used in APEX to evaluate the effect of climate change on future crop water requirements and Kc. The field data analysis indicated that, on average, farmer traditional practice (FTP) treatments used more water than wetting front detector (WFD) treatments. Using the soil water balance method, the average of the two treatments’ Kc values at the initial, mid, and late stages was 0.71, 1.21, and 0.8 for cabbage and 0.69, 1.27, and 0.86 for carrot, respectively. The APEX-simulated Kc has captured the FAO Kc pattern very well with the coefficient of determination (R-square) ranging between 0.5 and 0.74. The APEX simulation and the soil water balance estimated Kc also indicated a strong association with R-square ranging between 0.5 and 0.75 for cabbage and 0.66 and 0.96 for carrot. The projected climate change analysis indicated that the crop water demand is expected to increase in the future due to increasing temperatures. Under climate change scenarios, the growing season potential evapotranspiration will increase by 2.5, 5.1, and 6.0% in 2025, 2055, and 2085 compared to the baseline period, respectively. The simulated Kc indicated a higher coefficient of variation in 2085 with 19% for cabbage and 24% for carrot, while the 2025 period simulated Kc indicated the least coefficient of variation (16 and 21% for cabbage and carrot, respectively). The study shows that current irrigation planning with the available water resources should take into account higher crop water requirements in the region to reduce water scarcity risks.
Maize-grain zinc and iron concentrations as influenced by agronomic management and biophysical factors: a meta-analysis
Author(s): Kihara, Job Maguta; Sileshi, Gudeta W.; Bolo, Peter; Mutambu, Dominic; Senthilkumar, Kalimuthu; Sila, Andrew; Devkota Wasti, Mina; Saito, Kazuki (Springer (part of Springer Nature), 2025-08-05)
Date: 2024-08-05
Type: Journal Article
Status: Open access
Human Zn and Fe deficiencies can be reduced through agronomic biofortification, but information on factors influencing maize grain-Zn and -Fe levels remain scanty. This analysis: (1) Establishes the global distribution of Zn and Fe concentrations in maize grain; (2) assess the contribution of different agronomic practices to the effectiveness of Zn fertilizers for increasing grain yields, and Zn and Fe levels in maize grain; and (3) identify key biophysical factors and metrics to more effectively guide agronomic biofortification of Zn. Using 5874 data points in 138 published papers from 34 countries, we estimated a 7.5% probability of grainZn concentrations exceeding the benchmark target of 38 mg kg−1. Using 3187 data points from 65 studies across 27 countries we estimated a 8.5% probability of grain-Fe concentrations exceeding the target of 60 mg kg−1. Our 70-paper meta-analysis revealed that applying Zn and/or Fe in combination with inorganic NPK fertilizer can increase maize-grain-Zn and-Fe concentrations by
31% (p < 0.01) relative to the control (NPK only). In 52% and 37.5% of the studies respectively, grain-Zn and -Fe levels showed significant and concomitant increase with grain-yield increases. Soil organic matter, pH, soil-available Zn, organic input applications, and N, Zn and Fe application rates and methods were among the key factors influencing grain Zn and Fe. We conclude there is substantial room for increasing maize-grain Zn and Fe concentrations, and applying Zn, especially in combined soil and foliar applications, gives substantial increases in grain-Zn and -Fe concentrations. This global review reveals large data gaps on maize-grain nutrient levels, and we call for routine collection of such information in future research.
Assessing the impact of PGPR and water retention agents on bread wheat growth: an experimental study
Author(s): Habbadi, Khaoula; Guartoumi El Idriss, Meriem; El Iraqui El Houssaini, Salma; Maafa, Ilyass; Aoujil, Faiçal; Benbouazza, Abdellatif; Achbani, El-Hassan; Ferrahi, Moha (Asian Journal of agriculture and biology, 2025-03-01)
Date: 2025-02-20
Type: Journal Article
Status: Open access
Considering the imperative challenges posed by climate change, particularly the escalating instances of drought stress, optimizing wheat production stands as a critical goal for agricultural development. This experimental study delves into the pivotal role of Plant Growth-Promoting Rhizobacteria (PGPR) and Water Retention Agents (WRA) in bolstering the resilience of bread wheat crops to drought conditions. The study encompasses germination tests, field observations, and a comprehensive analysis of agronomic parameters, emphasizing the significance of PGPR and WRA in mitigating the adverse effects of water scarcity on wheat crops. The germination tests in Petri dishes reveal a substantial enhancement with the application of PGPR strains, showing higher rates (95% for Serratia nematodiphila strain GAB111 and 92% for Pseudomonas koreensis strain GAJ222) compared to the control. PGPR significantly increased root and shoot lengths, with significant increases observed. Field observations show the climatic impact on wheat development, with an accelerated growth cycle due to high temperatures and arid conditions. Further analyses reveal that WRA and PGPR significantly affect agronomic parameters such as the number of leaves, tillers, ears, and chlorophyll content. The study also assesses the impact on leaf temperature, wheat yield, plant-root development, and soil parameters such as organic matter and nutrient content. The combined use of WRA and PGPR shows promising results, highlighting their potential synergistic effects on wheat growth and development, especially in challenging environmental conditions. These findings offer practical solutions for enhancing wheat resilience and have broader implications for the sustainable development of agricultural systems confronting increasing climate-induced stresses.
Untargeted and targeted metabolomics approaches to characterise, select and advance cassava pre-breeding populations with enhanced whitefly tolerance
Author(s): Perez-Fons, Laura; Bohorquez-Chaux, Adriana; Gomez, Maria Isabel; Becerra, Augusto; Paul, Fraser (Wiley Online Library, 2025-05-27)
Date: 2025-05-27
Type: Journal Article
Status: Open access
Cassava (Manihot esculenta Crantz) provides food security for over 500 million people in Sub-Saharan Africa (SSA). Whitefly (Bemisia tabaci) is a pest in this region that results in ca. 50% crop yield losses. Thus, it is important to develop approaches that will generate new varieties tolerant to this pest to advance food security in the region. Two parental cassava varieties, ECU72 tolerant to whiteflies and COL2246 a susceptible line, have been used to generate bi-parental populations. The F1 generation has been screened for whitefly resistance, and progeny identified displaying enhanced tolerance. From designated F1 tolerant progeny, F2 families have been generated and phenotyped. The tolerance to whiteflies in the F2 population was further enhanced. Untargeted metabolomics was used to characterise whitefly susceptible and tolerant sub-groups. PCA of the molecular features generated clustering of accessions into whitefly resistant and susceptible groups, and differentiating metabolite biomarkers were identified. The most significant metabolite marker for resistance is the chemical feature 316.0924. Although not consistent among all whitefly resistance sub-groups, targeted LC–MS analysis revealed several pathways displaying perturbed levels. These include cyanogenic glycosides, apocarotenoids and the phenylpropanoid super-pathway comprising hydroxycinnamic acids, flavonoids and proanthocyanidins. Thus, the generation of a bi-parental population for whitefly tolerance/susceptibility enabled the identification of quantitative metabolite markers, the pathways contributing to tolerance, the underlying modes of action associated with resistance and the potential for the development of future high-throughput low-cost proxy markers. The approach also provides generic insights into future breeding strategies utilising bi-parental progeny for the enhancement of traits.
The economic contribution of camel-based livestock systems in North-African drylands: the case of East and South Moroccan provinces
Author(s): Amsidder, Lina; Alary, Veronique; Duteurtre, Guillaume; Mnaouer, Ihssane (SpringerOpen (part of Springer Nature))
Date: 2024-09-12
Type: Journal Article
Status: Open access
In Africa, camel herding is often viewed as a subsistence or ancient activity restricted to marginal drylands and arid or desert zones. However, camel products are increasingly sold in many cities, and camels are more and more used for tourist purposes. We can also see various public or private interventions in the arid zones aiming to develop processing units for milk or meat based on a business model. This present research aimed to evaluate the multiple economic and non-economic contributions of camel activities in North African drylands through analysis at the household and territorial levels using a multifunctional approach. Based on a study in five provinces of East and South Morocco, this article proposes a framework based on rural livelihoods and ecosystemic services for assessing the contribution of camel rearing to the rural economy and territorial development. It highlighted the multiple economic and non-economic functions of this activity, including domestic, trade, and services, as well as cultural attachment and local knowledge. We conclude by discussing current changes in camel herding, between supporting specialization for value chain participation and maintaining the overall sustainability of the camel systems in dryland areas.