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Recent Submissions

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Solar Powered Net-House
Author(s): Nejatian, Arash; Niane, Abdoul Aziz (International Center for Agricultural Research in the Dry Areas (ICARDA), 2024-09-27)
Date: 2024-09-27
Type: Poster
Status: Open access
Saving Resources, Maximized Yield, Efficient Space Utilization • AC/DC Hybrid Solar-Powered Energy • Closed Hydroponics Systems •Ultra-Low Energy Drippers • Root Zone Cooling •Vertical farming
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Soilless Vertical Farming
Author(s): Nejatian, Arash; Niane, Abdoul Aziz (International Center for Agricultural Research in the Dry Areas (ICARDA), 2024-09-29)
Date: 2024-09-29
Type: Poster
Status: Open access
Since 2002, ICARDA, in collaboration with National Agricultural Research Systems (NARS), has pioneered a high-density vertical soilless cultivation system in the Arabian Peninsula. Tailored for medium-sized farmers, this innovative system is optimized for the production of high-value crops such as herbs, leafy greens, and fruits.
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An Agro-economic comparison between Dwarf and Long green beans production in soilless production system
Author(s): Nejatian, Arash; Naqbi, Tahra; Ibrahim, Haliema; Ono, Eiichi (International Center for Agricultural Research in the Dry Areas (ICARDA), 2024-09-28)
Date: 2024-09-28
Type: Poster
Status: Open access
Study Objective Compare the yield and income of dwarf and long beans in a hydroponic system in the UAE. Methodology • Randomized Complete Block Design (RCBD) • Dwarf beans (SHADE): Vertical system (60m²) • Long beans (Saphiros): Flat system (120m²) • Location: 8x30m greenhouse at Al Dhaid • Irrigation: Closed Hydroponics System Key Findings Yield: Dwarf beans 1.98 kg/m²; Long beans 0.98 kg/m². Timing: Dwarf beans start earlier and produce one week longer
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Genome-wide analyses of cassava Pathogenesis-related (PR) gene families reveal core transcriptome responses to whitefly infestation, salicylic acid and jasmonic acid
Author(s): Irigoyen, Maria; Garceau, Danielle; Bohorquez-Chaux, Adriana; Becerra, Augusto; Perez-Fons, Laura; Paul, Fraser; Walling, Linda (BMC)
Date: 2020-01-29
Type: Journal Article
Status: Open access
Background Whiteflies are a threat to cassava (Manihot esculenta), an important staple food in many tropical/subtropical regions. Understanding the molecular mechanisms regulating cassava’s responses against this pest is crucial for developing control strategies. Pathogenesis-related (PR) protein families are an integral part of plant immunity. With the availability of whole genome sequences, the annotation and expression programs of the full complement of PR genes in an organism can now be achieved. An understanding of the responses of the entire complement of PR genes during biotic stress and to the defense hormones, salicylic acid (SA) and jasmonic acid (JA), is lacking. Here, we analyze the responses of cassava PR genes to whiteflies, SA, JA, and other biotic aggressors. Results The cassava genome possesses 14 of the 17 plant PR families, with a total of 447 PR genes. A cassava PR gene nomenclature is proposed. Phylogenetic relatedness of cassava PR proteins to each other and to homologs in poplar, rice and Arabidopsis identified cassava-specific PR gene family expansions. The temporal programs of PR gene expression in response to the whitefly (Aleurotrachelus socialis) in four whitefly-susceptible cassava genotypes showed that 167 of the 447 PR genes were regulated after whitefly infestation. While the timing of PR gene expression varied, over 37% of whitefly-regulated PR genes were downregulated in all four genotypes. Notably, whitefly-responsive PR genes were largely coordinately regulated by SA and JA. The analysis of cassava PR gene expression in response to five other biotic stresses revealed a strong positive correlation between whitefly and Xanthomonas axonopodis and Cassava Brown Streak Virus responses and negative correlations between whitefly and Cassava Mosaic Virus responses. Finally, certain associations between PR genes in cassava expansions and response to biotic stresses were observed among PR families. Conclusions This study represents the first genome-wide characterization of PR genes in cassava. PR gene responses to six biotic stresses and to SA and JA are demonstrably different to other angiosperms. We propose that our approach could be applied in other species to fully understand PR gene regulation by pathogens, pests and the canonical defense hormones SA and JA.
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Nitrous oxide emissions from cassava fields amended with organic and inorganic fertilizers
Author(s): Chirinda, Ngonidzashe; Trujillo, Catalina; Loaiza, Sandra; Salazar, Sandra; Luna Melendez, Jorge; Tong Encinas, Liz Alexandra; Becerra, Augusto; Tran, Thierry (Wiley (12 months), 2021-05-18)
Date: 2021-01-09
Type: Journal Article
Status: Timeless limited access
Cassava production requires nitrogen (N) inputs to drive processes such as protein synthesis. Nevertheless, N not taken up by cassava roots is subjected to microbial transformation resulting in nitrous oxide (N2O) production, a potent greenhouse gas. The temporal dynamics of soil N is partially influenced by the N source (i.e., organic or inorganic fertilizer) and the synchrony between N supply and demand. This study, which was conducted in Colombia on soils with high organic carbon and phosphorus contents, aimed at monitoring N2O emissions from cassava plots fertilized with organic (49.8 kg N ha-1 year-1) or inorganic fertilizers (22.7 kg N ha-1 year-1). Although the organic fertilizer (vermicompost) contained more than double the amount of N, cumulative N2O emissions from organic cassava production (1.28 kg N2O-N ha-1) were lower than those from inorganic fertilizer-based cassava production (1.74 kg N2O-N ha-1) system. This finding indicates that, if crop yields can be maintained, there is potential to reduce cassava production's environmental impact through organic fertilization on highly fertile soils. However, a transition to organic fertilization depends on the availability of sufficient amounts of organic fertilizers at the farm level. The N2O emissions in this study were higher than those predicted using the default IPCC emission factor, which confirmed the relevance of using country or regional specific emissions factors.