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Polyamines mediate the inhibitory effect of drought stress on nitrogen reallocation and utilization to regulate grain number in wheat
Author(s): Li, Juan; Li, Qi; Nian, GUO; Xian, Qinglin; Lan, Bing; Nangia, Vinay; Mo, Fei; Liu, Yang (Oxford University Press (OUP): Policy F - Oxford Open Option D, 2024-02-02)
Date: 2023-10-09
Type: Journal Article
Status: Timeless limited access
Drought stress poses a serious threat to grain formation in wheat. Nitrogen (N) plays crucial roles in plant organ development; however, the physiological mechanisms by which drought stress affects plant N availability and mediates the formation of grains in spikes of winter wheat are still unclear. In this study, we determined that pre-reproductive drought stress significantly reduced the number of fertile florets and the number of grains formed. Transcriptome analysis demonstrated that this was related to N metabolism, and in particular, the metabolism pathways of arginine (the main precursor for synthesis of polyamine) and proline. Continuous drought stress restricted plant N accumulation and reallocation rates, and plants preferentially allocated more N to spike development. As the activities of amino acid biosynthesis enzymes and catabolic enzymes were inhibited, more free amino acids accumulated in young spikes. The expression of polyamine synthase genes was down-regulated under drought stress, whilst expression of genes encoding catabolic enzymes was enhanced, resulting in reductions in endogenous spermidine and putrescine. Treatment with exogenous spermidine optimized N allocation in young spikes and leaves, which greatly alleviated the drought-induced reduction in the number of grains per spike. Overall, our results show that pre-reproductive drought stress affects wheat grain numbers by regulating N redistribution and polyamine metabolism.
Critical hydrologic impacts from climate change: addressing an urgent global need
Author(s): Falk, Jim; H. Gleick, Peter; Asayama, Shinichiro; Attig‑Bahar, Faten; Behera, Swadin; von Braun, Joachim; R. Colwell, Rita; K. Chapagain, Ashok; El-Beltagy, Adel; F. Kennel, Charles; Kimoto, Masahide; Koike, Toshio; Konde, Agnes Asiimwe; Koundouri, Phoebe; Mohamed Abd-Elmabod, Sameh Kotb; Lal, Rattan; Tseh Lee, Yuan; A. Murray, Cherry; Nangia, Vinay; Sapkota, Amy; Saijo, Tatsuyoshi; Serageldin, Ismail; Soussana, Jean-François; Takara, Kaoru; Takeuchi, Kazuhiko; Tran, Thong; Victor, David; Watanabe, Chiho; Wheeler, Kevin; Yasunari, Tetsuzo (Springer (part of Springer Nature), 2024-01-03)
Date: 2024-01-03
Type: Journal Article
Status: Open access
Consensus statement from the presenters and the International Advisory Committee of the Regional Action on Climate Change Symposium (RACC-15) held in conjunction with, and with the support of the Kyoto-based Science, Technology and Society Forum, 30 September 2023.
Assessing the Evolution of Stability and Maturity in Co-Composting Sheep Manure with Green Waste Using Physico-Chemical and Biological Properties and Statistical Analyses: A Case Study of Botanique Garden in Rabat, Morocco
Author(s): Lhaj, Majda Oueld; Rachid, Moussadek; Mouhir, Latifa; Mdarhri Alaoui, Meriem; Sanad, Hatim; Iben Halima, Oumaima; Zouahri, Abdelmjid (MPDI, 2024-07-19)
Date: 2024-07-19
Type: Journal Article
Status: Open access
Organic waste utilization stands as a pivotal approach to ecological and economic sustainability. This study aimed to assess the stability, maturity, and evolution of co-composts comprising various blends of green waste (GW) and sheep manure (SM). Employing a diverse array of physico-chemical and biological parameters, we investigated the co-composting process over 120 days. Three types of garden waste (mixture of green waste (MGW), fallen leaves (FL), and grass cutting (GC)) were utilized. The results revealed significant compost transformation, evident by odor and insect absence and a shift to dark brown coloration, indicating maturation. The compost C2, derived from FL, exhibited superior soil amendment potential. Significantly, it exhibited a pH level of 6.80, an EC of 2.45 mS/cm, and an OM content of 55%, along with a C/N ratio of 16.15. Analysis of the macronutrients revealed values of 1.98% for TN, 3.22% for TP, and 0.61% for K. Crucially, the compost showed no phytotoxic effects and boasted a high GI of 94.20% and a low respiration rate of 4.02 mg/50 g, indicating its stability and appropriateness for agricultural application. Our findings underscore compost’s potential as an eco-friendly soil amendment, offering valuable insights for sustainable agricultural management and supporting the circular economy.
Assessment of Soil Spatial Variability in Agricultural Ecosystems Using Multivariate Analysis, Soil Quality Index (SQI), and Geostatistical Approach: A Case Study of the Mnasra Region, Gharb Plain, Morocco
Author(s): Sanad, Hatim; Rachid, Moussadek; Mouhir, Latifa; Lhaj, Majda Oueld; Dakak, Houria; El Azhari, Hamza; Yachou, Hasna; Ghanimi, Ahmed; Zouahri, Abdelmajid (MPDI, 2024-05-23)
Date: 2024-05-23
Type: Journal Article
Status: Open access
Accurate assessment of soil quality is crucial for sustainable agriculture and soil conservation. Thus, this study aimed to assess soil quality in the agricultural ecosystem of the Mnasra region within the Gharb Plain of Morocco, employing a comprehensive approach integrating multivariate analysis and geostatistical techniques. Thirty soil samples were collected from the surface layers across thirty selected sites. The results showed significant variations in soil properties across the study area, influenced by factors such as soil texture, parent material, and agricultural practices. Pearson correlation and principal component analysis (PCA) were employed to analyze the relationships among soil properties and compute the Soil Quality Index (SQI). The SQI revealed values ranging from 0.48 to 0.74, with 46.66% of sampled soils classified as “Good” and 53.33% as “Fair”. Geostatistical analysis, particularly ordinary kriging (OK) interpolation and semivariogram modeling, highlighted the spatial variability of soil properties, aiding in mapping soil quality across the landscape. The integrated approach demonstrates the importance of combining field assessments, statistical analyses, and geospatial techniques for comprehensive soil quality evaluation and informed land management decisions. These findings offer valuable insights for decision-makers in monitoring and managing agricultural land to promote sustainable development in the Gharb region of Morocco.
Assessment of Groundwater Quality Using the Pollution Index of Groundwater (PIG), Nitrate Pollution Index (NPI), Water Quality Index (WQI), Multivariate Statistical Analysis (MSA), and GIS Approaches: A Case Study of the Mnasra Region, Gharb Plain, Morocco
Author(s): Sanad, Hatim; Mouhir, Latifa; Zouahri, Abdelmajid; Moussadek, Rachid; El Azhari, Hamza; Yachou, Hasna; Ghanimi, Ahmed; Lhaj, Majda Oueld; Dakak, Houria (MDPI, 2024-04-28)
Date: 2024-04-28
Type: Journal Article
Status: Open access
Groundwater, an invaluable resource crucial for irrigation and drinking purposes, significantly impacts human health and societal advancement. This study aims to evaluate the groundwater quality in the Mnasra region of the Gharb Plain, employing a comprehensive analysis of thirty samples collected from various locations, based on thirty-three physicochemical parameters. Utilizing tools like the Pollution Index of Groundwater (PIG), Nitrate Pollution Index (NPI), Water Quality Index (WQI), Irrigation Water Quality Index (IWQI), as well as Multivariate Statistical Approaches (MSA), and the Geographic Information System (GIS), this research identifies the sources of groundwater pollution. The results revealed Ca2+ dominance among cations and Cl− as the primary anion. The Piper and Gibbs diagrams illustrated the prevalent Ca2+-Cl− water type and the significance of water–rock interactions, respectively. The PIG values indicated that 86.66% of samples exhibited “Insignificant pollution”. NPI showed notable nitrate pollution (1.48 to 7.06), with 83.33% of samples rated “Good” for drinking based on the WQI. The IWQI revealed that 80% of samples were classified as “Excellent” and 16.66% as “Good”. Spatial analysis identified the eastern and southern sections as highly contaminated due to agricultural activities. These findings provide valuable insights for decision-makers to manage groundwater resources and promote sustainable water management in the Gharb region.