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In Senegal, numerous initiatives exist to cultivate Jatropha curcas L. (JCL) trees as a multipurpose energy crop, including for fuel. Thus, research on this drought-resistant shrub has been predominately focused on biofuel production from its seeds, while its potential for carbon (C) sequestration, which could be valuable in sink projects (i.e., afforestation, reforestation) under the Clean Development Mechanism (CDM) of the Kyoto protocol, has been largely unstudied. This study was carried out in Senegal’s Peanut basin to develop allometric equations for estimating biomass of individual JCL shrubs, JCL plantations, and determining their respective C storage potential. We discovered a three-stage evolution of JCL biomass accumulation. A slow build-up stage (1–3 years), followed by a fast production of biomass (3–4 years), and a relatively slower stage where certain fractions-root and leaf biomass-reach a plateau (4–5 years). The ratio between belowground and aboveground biomass varies from 53% (1 year after planting) and 26% (5 year after planting), with an average of 41%. We developed allometric models that provide a reliable estimation of the different biomass fractions of JCL and according to tree age. The models revealed that the stocks of biomass and C become relatively important from the fifth year with a storage capacity of 5.07 kg per tree. Most of the biomass and organic C are stored in the aboveground fractions of trees, suggesting that JCL plantations may be valuable for C sink and CDM projects.

The generalized oscillator strengths (GOS) of the argon transitions 3p6−3p5(3d, 4d, 5d) and 3p6−3p54f respectively for multiple strengths and are determined using the wavefunctions which have been generated from the CIV3 code of Hibbert. Calculations of these generalized oscillator strengths, as a function of momentum transfer, are also carried out respectively in the configuration interaction method and in the random phase approximation with exchange. The length and velocity forms have been used in this work. The gap between the absolute values of the generalized oscillator strength obtained in the theoretical calculations and those of the experimental results of Zhu et al have been noticeably reduced in the present work for the octupole excitations to 3p5(3d, 4d). This is due to the configuration interaction wavefunctions. The profiles and the positions of the extrema in the generalized oscillator strength have also received particular attention in the evaluation. The results of length and velocity form studies also show that the electron correlation effects are very significant for the excitations to 3p5(3d, 4d) but are found to have no great influence in the positions of the extrema. [ABSTRACT FROM AUTHOR]

Poor agricultural soil management practices and water use optimisation in irrigation are major challenges facing crop production in Senegal. To address these problems, a factorial experiment was conducted in 2021 and 2022 to investigate the effects of biochar on tomato growth and yield in sandy loam soil under different irrigation levels. Treatments included three biochar treatments (B2 = 30 t·ha -1 , B1 = 15 t·ha -1 , and B0 = 0 t·ha -1 ) and three irrigation levels (full irrigation, W0 = 8 L·m -2 ·day -1 ; medium deficit irrigation, W1 = 6 L·m -2 ·day -1, which is 75% of W0; and deficit irrigation, W2 = 4 L·m -2 ·day -1 , 50% of W0). The results showed that using biochar at 30 t·ha -1 significantly ( P < 0.05) reduced the bulk density of the soil by up to 8.3% under W1. In addition, biochar at 15 t·ha -1 and 30 t·ha -1 enhanced, regardless of the amount of water applied, the growth of tomato plants by at least 14% compared to that in the B0 treatment. Furthermore, the tomatoes' yields in biochar treatments B1 (12.58 t·ha -1 ) and B2 (12.45 t·ha -1 ) under W2 were greater than those under B0 (9.27 t·ha -1 ) under full irrigation. The combinations of biochar and the lowest irrigation water level (W2 and B1 or W2 and B2) can therefore allow a water economy of up to 50% of full irrigation without compromising yield. Our study concluded that biochar could sustainably reduce agricultural water consumption while increasing yields. To further understand the influence of biochar on sandy loam soil, more research is needed on its effects on soil moisture content at permanent wilting points and field capacity., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2024 Simeon Diedhiou et al.)

Background: Rhizosphere microbial communities are important components of the soil-plant continuum in paddy field ecosystems. These rhizosphere communities contribute to nutrient cycling and rice productivity. The use of fertilizers is a common agricultural practice in rice paddy fields. However, the long-term impact of the fertilizers usage on the rhizosphere microbial communities at different rice developmental stages remains poorly investigated. Here, we examined the effects of long-term (27 years) N and NPK-fertilization on bacterial and archaeal community inhabiting the rice rhizosphere at three developmental stages (tillering, panicle initiation and booting) in the Senegal River Delta., Results: We found that the effect of long-term inorganic fertilization on rhizosphere microbial communities varied with the rice developmental stage, and between microbial communities in their response to N and NPK-fertilization. The microbial communities inhabiting the rice rhizosphere at panicle initiation appear to be more sensitive to long-term inorganic fertilization than those at tillering and booting stages. However, the effect of developmental stage on microbial sensitivity to long-term inorganic fertilization was more pronounced for bacterial than archaeal community. Furthermore, our data reveal dynamics of bacteria and archaea co-occurrence patterns in the rice rhizosphere, with differentiated bacterial and archaeal pivotal roles in the microbial inter-kingdom networks across developmental stages., Conclusions: Our study brings new insights on rhizosphere bacteria and archaea co-occurrence and the long-term inorganic fertilization impact on these communities across developmental stages in field-grown rice. It would help in developing strategies for the successful manipulation of microbial communities to improve rice yields., (© 2023. The Author(s).)

The phytohormone jasmonic acid (JA) and its derivatives, collectively referred to as jasmonates, regulate many developmental processes, but are also involved in the response to numerous abiotic/biotic stresses. Thus far, powerful reverse genetic strategies employing perception, signalling or biosynthesis mutants have broadly contributed to our understanding of the role of JA in the plant stress response and development, as has the chemical gain-of-function approach based on exogenous application of the hormone. However, there is currently no method that allows for tightly controlled JA production in planta. By investigating the control of the JA synthesis pathway in bacteria-infected cotton (Gossypium hirsutum L.) plants, we identified a transcription factor (TF), named GhERF-IIb3, which acts as a positive regulator of the JA pathway. Expression of this well-conserved TF in cotton leaves was sufficient to produce in situ JA accumulation at physiological concentrations associated with an enhanced cotton defence response to bacterial infection., (© 2016 BSPP AND JOHN WILEY & SONS LTD.)

Primary hyperparathyroidism (PHPT) is rarely associated with the occurrence of acute or chronic pancreatitis. Hypercalcemia plays a major role in the pathogenesis. We report five cases of pancreatitis revealing PHPT. Patients and Methods . This is a retrospective study of 4 years, including all patients admitted to intensive care unit or gastroenterology department, for an acute or chronic pancreatitis revealing primary hyperparathyroidism. Results . We included 5 patients, all female, with mean age 54 years [40-76 years]. The PHPT was in all cases revealed by acute pancreatitis (AP). This one was oedematous in four cases and severe in one case. It occurred twice in calcified chronic pancreatitis (CCP). There was hypercalcemia in all cases. The PHPT was associated with a high rate of parathyroid hormone in 4 cases. The secreting lesion was an adenoma in 5 cases. Two patients had in addition bilateral renal calcifications. The outcome was favorable in 4 patients among whom 3 have had parathyroid surgery. A death was noted by superinfection of necrosis in the case of severe AP. Conclusion . The occurrence of pancreatitis during hyperparathyroidism is rare. Normal or elevated calcemia during acute or chronic pancreatitis should always get attention.

Root nodule symbioses (RNS) allow plants to acquire atmospheric nitrogen by establishing an intimate relationship with either rhizobia, the symbionts of legumes or Frankia in the case of actinorhizal plants. In legumes, NIN (Nodule INception) genes encode key transcription factors involved in nodulation. Here we report the characterization of CgNIN, a NIN gene from the actinorhizal tree Casuarina glauca using both phylogenetic analysis and transgenic plants expressing either ProCgNIN::reporter gene fusions or CgNIN RNAi constructs. We have found that CgNIN belongs to the same phylogenetic group as other symbiotic NIN genes and CgNIN is able to complement a legume nin mutant for the early steps of nodule development. CgNIN expression is correlated with infection by Frankia, including preinfection stages in developing root hairs, and is induced by culture supernatants. Knockdown mutants were impaired for nodulation and early root hair deformation responses were severely affected. However, no mycorrhizal phenotype was observed and no induction of CgNIN expression was detected in mycorrhizas. Our results indicate that elements specifically required for nodulation include NIN and possibly related gene networks derived from the nitrate signalling pathways., (© 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.)