In Senegal, tomato (<i><span style="font-family:Verdana;">Solanum lycopersicum</span></i><span style="font-family:Verdana;"> L.) cultivation is affected by salinity in...In Senegal, tomato (<i><span style="font-family:Verdana;">Solanum lycopersicum</span></i><span style="font-family:Verdana;"> L.) cultivation is affected by salinity in many agro-ecological zones. The selection of salt tolerant varieties would be an alternative solution to enhance the production. Thus, germination and growth are studied under axenic conditions for five varieties of tomato subjected to increasing concentrations of NaCl [0, 35, 70 and 105 mM], and supplemented in an MS/2 medium for 30 days. The results reveal that salt negatively affects the evaluated parameters. The </span><i><span style="font-family:Verdana;">Rodeo</span></i><span style="font-family:Verdana;"> and </span><i><span style="font-family:Verdana;">Lady Nema </span></i><span style="font-family:Verdana;">varieties have the lowest final germination rates (50%) unlike the </span><i><span style="font-family:Verdana;">Mongal</span></i><span style="font-family:Verdana;"> variety (55%). These last two varieties have a decrease of 71.78% and 81.28% in the height of the stem, respectively, in the presence of NaCl at [105 mM] while that of the </span><i><span style="font-family:Verdana;">Rodeo</span></i><span style="font-family:Verdana;"> variety is 70%. The </span><i><span style="font-family:Verdana;">Xewel</span></i><span style="font-family:Verdana;"> variety has the greatest average number of leaves in the presence of [NaCl 35 mM] (4.95 leaves) and [NaCl 70 mM] (4.77 leaves). The </span><i><span style="font-family:Verdana;">Lady Nema</span></i><span style="font-family:Verdana;"> variety records the longest taproot length (2.99 cm) unlike the </span><i><span style="font-family:Verdana;">Rodeo</span></i><span style="font-family:Verdana;"> variety (2.25 cm) at [NaCl 105 mM]. The </span><i><span style="font-family:Verdana;">Ganila</span></i><span style="font-family:Verdana;"> variety reveals the highest number of secondary roots at the concentrations of [0, 35 and 105 mM] of NaCl with, respectively, 44.12, 29.25, and 4.25 roots. The </span><i><span style="font-family:Verdana;">Lady Nema</span></i><span style="font-family:Verdana;"> variety records the highest fresh weight of aerial (0.055 g) and root parts (0.014 g) and the lowest root dry weights (0.0023 g). These results allow to conclude that the </span><i><span style="font-family:Verdana;">Lady Nema </span></i><span style="font-family:Verdana;">and</span><i><span style="font-family:Verdana;"> Mongal</span></i><span style="font-family:Verdana;"> varieties seem more tolerant, </span><i><span style="font-family:Verdana;">Ganila </span></i><span style="font-family:Verdana;">and</span><i><span style="font-family:Verdana;"> Xewel</span></i><span style="font-family:Verdana;"> are moderately tolerant and </span><i><span style="font-family:Verdana;">Rodeo</span></i><span style="font-family:Verdana;"> is more sensitive to the presence of salt.</span>展开更多
This study presents an analysis of the impact of mycorrhizal inoculation on growth under salt stress of date palms cultivars Nakhla hamra (NHH) and Tijib known in the Sahel for their earliness in flowering and fruitin...This study presents an analysis of the impact of mycorrhizal inoculation on growth under salt stress of date palms cultivars Nakhla hamra (NHH) and Tijib known in the Sahel for their earliness in flowering and fruiting. The seedlings were grown in a greenhouse on a sandy substrate watered to field capacity every two days and were subjected to increasing levels of NaCl (0, 1, 2, 4, 6, 8 and 16 g·L-1) and then inoculated with 5 strains of Glomus (G. aggregatum, G. intraradices, G. verriculosum, G. mosseae, G. fasciculatum). The experimental design was a randomized complete block with three factors (cultivars: Tijib and Nakhla Hamra x seven levels of NaCl concentrations x six levels of inoculum). The results showed that in the absence of NaCl, G. verriculosum significantly enhanced shoot growth: 33.5 cm against 30.3 cm in the control and roots growth: 81.5 cm against 78 cm in NHH, while in Tijib, the growth is stimulated by Glomus fasciculatum: 33.8 cm against 32.7 cm for stems and 90 cm against 86 cm for the roots of inoculated plants and controls. In contrast, in the presence of NaCl 8 g·L-1, NHH has a better growth in the presence of G. intraradices: 37.3 cm against 30.6 cm for stems and 77 cm against 73 for roots, while Tijib grows better in the presence of G. fasciculatum with respectively 31.9 cm against 31.7 cm and 51.27 cm against 51.6 cm for stems and roots of inoculated plants and controls. Biochemical analysis revealed that changes in levels of proline depend on the cultivar, the mycorrhizal strain used and concentrations of NaCl applied. These results open the prospect of using mycorrhizal fungi to improve the productivity of palm trees in the Sahel.展开更多
<em>Annona senegalensis</em> (Pers.) or Annone from Senegal is a species found in the West African savannah and para-littoral sands. It offers real possibilities of socio-economic use, particularly in the ...<em>Annona senegalensis</em> (Pers.) or Annone from Senegal is a species found in the West African savannah and para-littoral sands. It offers real possibilities of socio-economic use, particularly in the medical, nutritional, ecosystem conservation and poverty alleviation fields. However, this wild species remained not fully exploited despite its potentialities. As a result, there is a need to regenerate this species;therefore, the<em> in vitro</em> propagation from adult material was undertaken. For this purpose, axillary nodes from plant regrowth taken from elderly subjects were aseptically introduced into different media enriched or not with phytohormones. Among the 3 culture media tested, that of Murashige and Skoog (MS, 1962) was the most reactive and made it possible to develop a micropropagation protocol for adult material of <em>A. senegalensis</em>. Thus, the introduction of these explants in media containing cytokinins (BAP and Kinetin) significantly increased the reactivity compared to media without hormones. If the best average numbers of shoots (2.3) and nodes (5.3) are obtained in MS + BAP 2 mg<span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">·</span></span></span>L<sup><span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">−</span></span></span>1</sup>, with a reactivity of 91.66%, the addition of 0.1 mg<span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">·</span></span></span>L<sup><span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">−</span></span></span>1</sup> NAA gave the best average length (8.25 cm) of vitroplants. An induction time of 3 days into darkness with IBA at 50 mg<span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">·</span></span></span>L<sup><span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">−</span></span></span>1</sup>, followed by a transfer to hormone-free expression medium (MS/2) under light, resulted in a rooting rate of 58.33%. After the gradual weaning of the young plants in a mini-greenhouse, under shade for 3 weeks, 50% of the plants survived. This <em>in vitro</em> regeneration protocol can therefore be adopted for the clonal propagation of adult material of <em>A. senegalensis</em>. However, the rooting rate can be improved by trying other hormonal combinations based on auxins or by considering <em>ex</em>-<em>vitro</em> rooting during shade weaning.展开更多
Water is the main limiting factor in the cultivation of tomato (<i>Solanum lyco<span>persicum</span></i><span> L.) in Senegal. Thus, the selection of varieties tolerant to water st</sp...Water is the main limiting factor in the cultivation of tomato (<i>Solanum lyco<span>persicum</span></i><span> L.) in Senegal. Thus, the selection of varieties tolerant to water st</span>ress would be an alternative solution for their production. <i>In vitro </i>germination, growth, total chlorophyll and proline levels were studied in five varieties of tomato subjected to increasing osmotic pressures (0, 5, 10 and 15 kPa) thanks to the PEG-8000 incorporated in an MS/2 medium for 30 days. A strong sen<span>sitivity to water stress for <i>in vitro</i> seed germination in the <i>Rodeo</i> variety (4</span>1%) is recorded at 5 kPa and maintained at 15 kPa (20.83%) while it was only noticed at 15 kPa in the other tomato varieties. The <i>Xewel</i> and <i>Lady Nema</i> varieties obtained the smallest reductions in the number of leaves of vitroplants, with 30.79% and 27.97% at 15 kPa, respectively, and the <i>Rodeo</i> variety recorded a reduction of 35.97%. From 5 kPa, the varieties record reductions in <span>the number of secondary roots of more than 15%. The effect of osmotic pr</span>essures on decreasing the taproot height and length is not significant. The <i>Xewel </i>variety had the highest average fresh (0.483 g) and dry (0.082 g) weights of the aerial part at 15 kPa and the <i>Rodeo</i> variety </span><span style="font-family:"">had </span><span style="font-family:"">the lowest ones (0.308 g and 0.0501 g). The <i>Lady Nema</i> variety had the highest average fresh (0.171 g) and dry (0.039 g) root weights and the <i>Rodeo</i> variety</span><span style="font-family:""> had</span><span style="font-family:""> the lowest ones (0.086 and 0.020 g). The vitroplants of <i>Rodeo </i>variety recorded the highest decreases in total chlorophyll contents at all osmotic pressures and the lowest increase in proline content (53.37%) at 15 kPa. <i>A contrario</i>, the <i>Xewel</i> variety recorded the greatest increase in proline content (116.26%). Ultimately, the vitroplants of <i>Lady Nem</i>a and <i>Xewe</i>l varieties were more tolerant to water stress, the <i>Ganila </i>and<i> Mongal </i>varieties were moderately tolerant and the <i>Rodeo</i> variety was the most sensitive.展开更多
The microtuber is considered one of the most effective means of spreading basic materials, as well as transporting and preserving potato germplasm varieties. To define the optimal conditions for the potato microtuber ...The microtuber is considered one of the most effective means of spreading basic materials, as well as transporting and preserving potato germplasm varieties. To define the optimal conditions for the potato microtuber in vitro germination of Aida, Atlas and Odessa varieties, the effects of temperature, physiological age and grade (size) were evaluated. The study conducted at three different temperature levels has demonstrated that the most favorable temperature for microtuber germination at a higher and faster germination rate was 25℃, regardless of the variety. In addition, microtubers of large caliber, greater than 4 mm, germinate more quickly, with a higher germination rate, than smaller size ones (less than 4 mm) for all genotypes. For Atlas, Aida and Odessa varieties, a germination rate equal to 86.66%, 70% and 70% respectively, was obtained for microtubers with a caliber superior to 4 mm. Physiological age influences microtuber germination. The mean length of sprouts, reached after a 7 week incubation period, was more marked at “multiple sprout” and “branched sprout” stages than at a “monosprout” stage. The average length was 2.35 cm, 2.48 cm and 1.5 cm, respectively. Thus, it is necessary to plant microtubers at a “multiple sprout” stage to optimize their yield in plants and minitubers.展开更多
Cowpea is one of the most important legume grains in the sub-Saharan region of Africa used for human consumption and animal feed,but its production is hampered by biotic and abiotic constraints raising the need to bro...Cowpea is one of the most important legume grains in the sub-Saharan region of Africa used for human consumption and animal feed,but its production is hampered by biotic and abiotic constraints raising the need to broaden its genetic basis.For this purpose,seeds of two cowpea varieties Melakh and Yacine were irradiated with 300 and 340 Gy of gamma-ray,respectively.The developed mutant populations were agromorphologically characterized from M5 to M7,while the genetic diversity of the latter was evaluated using 13 ISSR markers.Based on the agromorphological characterization,variation of flower color,pod length,seed coat color,and seed weight with 78.01,68.29,94.48,and 57.58%heritability,respectively,were recorded in the mutant lines.PCA analyses allowed to identify the elite mutants based on their agromorphological traits,while Pearson’s correlation results revealed a positive correlation between yield and yield component traits.Three subpopulations were identified through STRUCTURE analyses,but the assignment of the individuals in each group was improved using DAPC(Discriminant Analysis of Principal Components)analysis.Analysis of Molecular Variance revealed that the majority(85%)of the variance rather existed within groups than among(15%)groups.Finally,our study allowed us to select new promising mutant genotypes that could be tested for multi-locational trials to evaluate their agronomic performance.展开更多
The residual effects of sucrose concentrations (80 or 100 g·L-1) and hormonal treatments (BAP + Kinetin or Coumarin) of tuberization medium on in vitro microtubers germination of three potato varieties (Solanum t...The residual effects of sucrose concentrations (80 or 100 g·L-1) and hormonal treatments (BAP + Kinetin or Coumarin) of tuberization medium on in vitro microtubers germination of three potato varieties (Solanum tuberosum L.) so called Aida, Atlas and Odessa, are described. After 3 weeks of incubation at 28℃ ± 1℃, 70% of Aida microtubers variety, previously formed in the MT2 medium [MS/2 + 80 g·L-1 Sucrose], germinated. The best germination rate for varieties Atlas (100%) and Odessa (66.66%) was obtained on microtubers previously formed in the medium MT2 [MS/2 + 100 g·L-1 Sucrose]. The addition of hormones in the tuberization medium allowed optimizing the microtubers germination of the Aida variety unlike the other varieties. Indeed, for the Aida variety, the combination M5 [Kin 2.5 mg·L-1 + Coum 0.025 mg·L-1 + Sucrose 80 g·L-1] increased the germination rate from 70% up to 93.33%. The best germination rate (90%), noticed with microtubers of Atlas variety, initially formed in M2 medium [Kin 1 mg·L-1 + BAP 1 mg·L-1 + Sucrose 100 g·L-1], was lower than that one (100%) obtained on medium without hormones. For Odessa variety, the maximum germination rate (53.33%) of microtubers, from the medium M4 [Kin 2.5 mg·L-1 + BAP 1 mg·L-1 + Sucrose 100 g·L-1], was also lower than that one (66.66%) observed in the medium without hormones. Aida and Atlas varieties thus offer a better germination rate than Odessa after their cold storage.展开更多
Salinity is a major problem that seriously impacts agricultural production, particularly that of tomato (Solanum lycopersicum L.). However, the plant has the ability to associate with Arbuscular Mycorrhizal Fungi to b...Salinity is a major problem that seriously impacts agricultural production, particularly that of tomato (Solanum lycopersicum L.). However, the plant has the ability to associate with Arbuscular Mycorrhizal Fungi to better tolerate salt stress. Thus, thanks to the extension of the AMF hyphae, the hydromineral nutrition and the tolerance to excess toxic ions (Na<sup>+</sup> and Cl<sup>-</sup>) of the plant are optimized. In this context, the contribution of AMF to the salt stress tolerance of two tomato varieties under semi-controlled conditions was studied. To do this, the frequency and intensity of mycorrhization, the relative mycorrhizal dependency, the survival rates, the aerial and root dry weights, the mineral (P, K<sup>+</sup>, Na<sup>+</sup>) and proline contents of the plants subjected to four levels of salinity [0, 70, 140 and 210 mM of NaCl] were evaluated. All the parameters assessed appeared to be dependent on the variety, the fungal strain and the NaCl concentration. With the Lady Nema variety, inoculation with the Claroideoglomus etunicatum strain at [NaCl 140 mM] resulted in the highest frequencies (54%), intensities (40.47%), and relative mycorrhizal dependencies (19.65%). This same symbiotic couple recorded high survival rates (55%) and aerial (2.03 g) and root (0.50 g) dry weights. Significant contents of K<sup>+ </sup>(Leaves: 7.5 mg⋅g<sup>-1</sup>;Roots: 4.4 mg⋅g<sup>-1</sup> of dry matter), P (Leaves: 15.15 mg⋅g-1</sup> of dry matter) and proline (975 nmoles⋅g-1</sup> of fresh matter) were also recorded by this pair, with the lowest Na<sup>+</sup> contents (Leaves: 1.93 mg⋅g-1</sup>;Roots: 0.96 mg⋅g-1</sup> of dry matter). For the Mongal variety, at [NaCl 140 mM], the highest frequencies (50.36%), intensities (35.14%) and relative mycorrhizal dependencies (43.95%) were obtained thanks to inoculation with Rhizophagus fasciculatus. The highest survival rates (59%) and aerial (2.58 g) and root (0.79 g) dry weights were also obtained with this symbiotic couple. The contents of K<sup>+</sup> (Leaves: 6.1 mg⋅g-1</sup>;Roots: 3.09 mg⋅g-1 </sup>of dry matter), P (Leaves: 12.49 mg⋅g-1</sup> of dry matter) and proline (942 nmoles⋅g-1</sup> of fresh matter) the most important and those in Na<sup>+</sup> the lowest (Leaves: 2.03 mg⋅g-1</sup>;Roots: 1.53 mg⋅g-1</sup> of dry matter) were also recorded for this same pair. Thus, the best fungal partner for the Lady Nema variety is C. etunicatum, followed by F. mosseae and R. fasciculatus, while for the Mongal variety it is R. fasciculatus, followed by C. etunicatum and F. mosseae.展开更多
Annona senegalensis is a savannah species present in the wild in tropical and sub-tropical African regions. It is used by the local populations for its many economic, pharmacological, nutritional and ecological intere...Annona senegalensis is a savannah species present in the wild in tropical and sub-tropical African regions. It is used by the local populations for its many economic, pharmacological, nutritional and ecological interests. However, the strong pressure exerted on this species as well as the increasing degradation of the ecosystems, in which it evolves, seriously compromise its sustainability and development. Conventional methods of vegetative propagation are not sufficient to ensure its durable regeneration and the renewal of endemic populations in Senegal. In this context, it was undertaken in vitro propagation, from 30 days old juvenile seedlings. Thus, axillary, cotyledonary and apical nodes were in vitro cultured in Murashige and Skoog (1962) medium (MS), with different concentrations of cytokinins and/or auxins. BAP used alone at 2 mg•L<sup>−1</sup> proved to be more beneficial for micropropagation of different types of explants compared to Kinetin used alone or in combination with BAP, especially for axillary and cotyledonary nodes. The BAP-NAA combination allowed to have a better elongation of newly formed shoots. For shoots of apical and cotyledonary nodes origin, a rhizogenic induction of 5 days, with IBA at 25 mg•L<sup>−1</sup>, resulted in a better rooting rate with, respectively, 75% (for 2.22 roots) and 66.67% (for 4.17 roots). For newly formed shoots of axillary origin, a 24-hour rooting induction with IBA at 50 mg•L<sup>−1</sup> gave a rooting rate of 58.33% (for 2.4 roots). After 30 days of acclimatization, the survival rate was 75% for the young plants from the apices and 83.33% for those originating from the cotyledonary and axillary nodes. This protocol can therefore be adopted for the in vitro clonal propagation of A. senegalensis juvenile material.展开更多
In arid and semi-arid regions, the growth and development of cultivated plants, especially tomato (Solanum lycopersicum L.), are severely limited by water deficit. Thus, to cope with this constraint, the plant establi...In arid and semi-arid regions, the growth and development of cultivated plants, especially tomato (Solanum lycopersicum L.), are severely limited by water deficit. Thus, to cope with this constraint, the plant establishes symbiotic relationships with arbuscular mycorrhizal fungi (AMF) in the soil whose extension of the hyphae allows a better and deeper exploration;this notably improves the hydromineral nutrition of the plant. Therefore, the choice of fungal partner becomes crucial for the establishment of a crop in water-deficient soil. In this context, the contribution of AMF to the water stress tolerance of two varieties of tomato plants was assessed under semi-controlled conditions. Parameters, such as the mycorrhizal frequency, intensity of mycorrhization, relative mycorrhizal dependency, growth, and biochemical parameters (carbon, nitrogen, phosphorus, and proline contents) of plants subjected to three levels of water stress (T100, T70, and T30), were evaluated. The highest frequencies and intensities of mycorrhization and relative mycorrhizal dependencies were obtained with plants of the Xewel variety inoculated with Rhizophagus fasciculatus (F: 95.24%, 88.35%, and 13.64%;M: 40.52%, 37.52%, and 11.22%;D: 23.7%, 54.4%, and 78.82%) and in those of the Lady Nema variety inoculated with Claroideoglomus etunicatum (F: 95.12%, 87.01%, and 15.25%;M: 40.66%, 37.99%, and 11.42%;D: 19.27%, 57.01%, and 70.98%), respectively at water regimes of T100, T70 and T30. These same symbiotic couples recorded, at T30, the best survival rates (+ 40%) and the higher aerial (77% and 74%) and root dry weights (80% and 59%). Plants of the Xewel variety inoculated with R. fasciculatus recorded the highest contents of carbon (T70: 30.59% and T30: 21.55%) and phosphorus (T70: 0.18% and T30: 0.17%). Plants of the Lady Nema variety recorded the highest nitrogen contents with 3.51% and 3.20%, respectively at T70 and T30. Plants of the Lady Nema variety, inoculated with C. etunicatum, also recorded the highest proline contents (572.25, 739.44, and 1165 nmoles•g<sup>−1</sup> of fresh material), followed by those of the Xewel variety inoculated with R. fasciculatus (580.36, 763.65, and 1112.11 nmoles•g<sup>−1</sup> of fresh matter), respectively at T100, T70, and T30. For the Lady Nema variety, the best fungal partner is C. etunicatum, followed by R. fasciculatus and, finally, Funneliformis mosseae. However, for the plants of the Xewel variety, R. fasciculatus is the most efficient, followed by F. mosseae and C. etunicatum. This suggests that, in tomatoes, the efficiency of mycorrhizal symbiosis under water stress conditions is not only dependent on the host plant but on both associated symbiotic partners. Hence, it is a need for screening to identify the best symbiotic couples in a stressful environment.展开更多
Sesame is an important oilseed crop in Africa and Asia, owing to its high nutritional quality seed and market value. Variation in sesame seed components including oil, oleic acid,linoleic acid, and protein was investi...Sesame is an important oilseed crop in Africa and Asia, owing to its high nutritional quality seed and market value. Variation in sesame seed components including oil, oleic acid,linoleic acid, and protein was investigated by near-infrared reflectance spectrometry in 139 samples collected from different countries. Oil and protein contents were between 40.8%and 60.3%(mean 53.0%) and 15.5% to 25.5%(mean 20.4%), respectively. Linoleic acid,ranging from 31.8% to 52.4%(mean 46%) was more abundant than oleic acid(31.8%–50.6%,mean 38.1%). Light-seeded samples displayed higher nutritional quality, as they were richer in oil, protein, and linoleic acid than dark seeds. Samples from Africa had higher oil and linoleic acid contents, while Asian samples had higher oleic content. The analysis revealed West African sesame cultivars containing especially high levels of seed components, which may command high market values. Two clusters of sesame samples grouped by seed composition were obtained, including one cluster with high oil and oleic acid content and the other with high protein and linoleic acid content. This study revealed that sesame samples from Africa and Asia harbor high variation for major seed components and also provided background information for breeding high-nutrition varieties according to the demands of sesame seed markets.展开更多
The potato (</span><i><span style="font-family:Verdana;">Solanum tuberosum</span></i><span style="font-family:Verdana;"> L.) is a vegetable that ranks fifth in t...The potato (</span><i><span style="font-family:Verdana;">Solanum tuberosum</span></i><span style="font-family:Verdana;"> L.) is a vegetable that ranks fifth in the world for human consumption. Its importance is growing more and more in the Senegalese diet. However, the potato production in Senegal does not meet the needs of the market, which maintains dependence on the outside for the supply of quality seeds. In addition, these imported seeds do not often have phytosanitary qualities required for local production in the Sahelian zone. The </span><i><span style="font-family:Verdana;">in vitro </span></i><span style="font-family:Verdana;">production of microtubers, used as seed, has been shown to be one of the mos</span><span style="font-family:Verdana;">t efficient means for propagation of basic material. To overcome the constraints linked to the supply and availability of potato seeds, with high germination capacity, the impact of the microtuber size on the yield of the plants under semi-controlled conditions was examined. The pre-germinated</span><span style="font-family:Verdana;"> microtubers were produced </span><i><span style="font-family:Verdana;">in vitro </span></i><span style="font-family:Verdana;">from vitroplants of 3 different varieties (</span><i><span style="font-family:Verdana;">Aida</span></i><span style="font-family:Verdana;">,</span><i><span style="font-family:Verdana;"> Atlas</span></i><span style="font-family:Verdana;">,</span><i><span style="font-family:Verdana;"> Odessa</span></i><span style="font-family:Verdana;">) adapted to the edaphic-climatic conditions of Senegal. The effects of the seed sizes of microtubers, greater than 4 mm, sown under semi-controlled conditions, on the yield of the plants</span></span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> result in an increase in the ratio, in the vegetative development of the plants, but also in the number and size of the minitubers harvested. The yield of the plants also depends on the variety. It can therefore be envisaged to produce local potato seeds from microtubers and minitubers.展开更多
文摘In Senegal, tomato (<i><span style="font-family:Verdana;">Solanum lycopersicum</span></i><span style="font-family:Verdana;"> L.) cultivation is affected by salinity in many agro-ecological zones. The selection of salt tolerant varieties would be an alternative solution to enhance the production. Thus, germination and growth are studied under axenic conditions for five varieties of tomato subjected to increasing concentrations of NaCl [0, 35, 70 and 105 mM], and supplemented in an MS/2 medium for 30 days. The results reveal that salt negatively affects the evaluated parameters. The </span><i><span style="font-family:Verdana;">Rodeo</span></i><span style="font-family:Verdana;"> and </span><i><span style="font-family:Verdana;">Lady Nema </span></i><span style="font-family:Verdana;">varieties have the lowest final germination rates (50%) unlike the </span><i><span style="font-family:Verdana;">Mongal</span></i><span style="font-family:Verdana;"> variety (55%). These last two varieties have a decrease of 71.78% and 81.28% in the height of the stem, respectively, in the presence of NaCl at [105 mM] while that of the </span><i><span style="font-family:Verdana;">Rodeo</span></i><span style="font-family:Verdana;"> variety is 70%. The </span><i><span style="font-family:Verdana;">Xewel</span></i><span style="font-family:Verdana;"> variety has the greatest average number of leaves in the presence of [NaCl 35 mM] (4.95 leaves) and [NaCl 70 mM] (4.77 leaves). The </span><i><span style="font-family:Verdana;">Lady Nema</span></i><span style="font-family:Verdana;"> variety records the longest taproot length (2.99 cm) unlike the </span><i><span style="font-family:Verdana;">Rodeo</span></i><span style="font-family:Verdana;"> variety (2.25 cm) at [NaCl 105 mM]. The </span><i><span style="font-family:Verdana;">Ganila</span></i><span style="font-family:Verdana;"> variety reveals the highest number of secondary roots at the concentrations of [0, 35 and 105 mM] of NaCl with, respectively, 44.12, 29.25, and 4.25 roots. The </span><i><span style="font-family:Verdana;">Lady Nema</span></i><span style="font-family:Verdana;"> variety records the highest fresh weight of aerial (0.055 g) and root parts (0.014 g) and the lowest root dry weights (0.0023 g). These results allow to conclude that the </span><i><span style="font-family:Verdana;">Lady Nema </span></i><span style="font-family:Verdana;">and</span><i><span style="font-family:Verdana;"> Mongal</span></i><span style="font-family:Verdana;"> varieties seem more tolerant, </span><i><span style="font-family:Verdana;">Ganila </span></i><span style="font-family:Verdana;">and</span><i><span style="font-family:Verdana;"> Xewel</span></i><span style="font-family:Verdana;"> are moderately tolerant and </span><i><span style="font-family:Verdana;">Rodeo</span></i><span style="font-family:Verdana;"> is more sensitive to the presence of salt.</span>
文摘This study presents an analysis of the impact of mycorrhizal inoculation on growth under salt stress of date palms cultivars Nakhla hamra (NHH) and Tijib known in the Sahel for their earliness in flowering and fruiting. The seedlings were grown in a greenhouse on a sandy substrate watered to field capacity every two days and were subjected to increasing levels of NaCl (0, 1, 2, 4, 6, 8 and 16 g·L-1) and then inoculated with 5 strains of Glomus (G. aggregatum, G. intraradices, G. verriculosum, G. mosseae, G. fasciculatum). The experimental design was a randomized complete block with three factors (cultivars: Tijib and Nakhla Hamra x seven levels of NaCl concentrations x six levels of inoculum). The results showed that in the absence of NaCl, G. verriculosum significantly enhanced shoot growth: 33.5 cm against 30.3 cm in the control and roots growth: 81.5 cm against 78 cm in NHH, while in Tijib, the growth is stimulated by Glomus fasciculatum: 33.8 cm against 32.7 cm for stems and 90 cm against 86 cm for the roots of inoculated plants and controls. In contrast, in the presence of NaCl 8 g·L-1, NHH has a better growth in the presence of G. intraradices: 37.3 cm against 30.6 cm for stems and 77 cm against 73 for roots, while Tijib grows better in the presence of G. fasciculatum with respectively 31.9 cm against 31.7 cm and 51.27 cm against 51.6 cm for stems and roots of inoculated plants and controls. Biochemical analysis revealed that changes in levels of proline depend on the cultivar, the mycorrhizal strain used and concentrations of NaCl applied. These results open the prospect of using mycorrhizal fungi to improve the productivity of palm trees in the Sahel.
文摘<em>Annona senegalensis</em> (Pers.) or Annone from Senegal is a species found in the West African savannah and para-littoral sands. It offers real possibilities of socio-economic use, particularly in the medical, nutritional, ecosystem conservation and poverty alleviation fields. However, this wild species remained not fully exploited despite its potentialities. As a result, there is a need to regenerate this species;therefore, the<em> in vitro</em> propagation from adult material was undertaken. For this purpose, axillary nodes from plant regrowth taken from elderly subjects were aseptically introduced into different media enriched or not with phytohormones. Among the 3 culture media tested, that of Murashige and Skoog (MS, 1962) was the most reactive and made it possible to develop a micropropagation protocol for adult material of <em>A. senegalensis</em>. Thus, the introduction of these explants in media containing cytokinins (BAP and Kinetin) significantly increased the reactivity compared to media without hormones. If the best average numbers of shoots (2.3) and nodes (5.3) are obtained in MS + BAP 2 mg<span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">·</span></span></span>L<sup><span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">−</span></span></span>1</sup>, with a reactivity of 91.66%, the addition of 0.1 mg<span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">·</span></span></span>L<sup><span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">−</span></span></span>1</sup> NAA gave the best average length (8.25 cm) of vitroplants. An induction time of 3 days into darkness with IBA at 50 mg<span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">·</span></span></span>L<sup><span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">−</span></span></span>1</sup>, followed by a transfer to hormone-free expression medium (MS/2) under light, resulted in a rooting rate of 58.33%. After the gradual weaning of the young plants in a mini-greenhouse, under shade for 3 weeks, 50% of the plants survived. This <em>in vitro</em> regeneration protocol can therefore be adopted for the clonal propagation of adult material of <em>A. senegalensis</em>. However, the rooting rate can be improved by trying other hormonal combinations based on auxins or by considering <em>ex</em>-<em>vitro</em> rooting during shade weaning.
文摘Water is the main limiting factor in the cultivation of tomato (<i>Solanum lyco<span>persicum</span></i><span> L.) in Senegal. Thus, the selection of varieties tolerant to water st</span>ress would be an alternative solution for their production. <i>In vitro </i>germination, growth, total chlorophyll and proline levels were studied in five varieties of tomato subjected to increasing osmotic pressures (0, 5, 10 and 15 kPa) thanks to the PEG-8000 incorporated in an MS/2 medium for 30 days. A strong sen<span>sitivity to water stress for <i>in vitro</i> seed germination in the <i>Rodeo</i> variety (4</span>1%) is recorded at 5 kPa and maintained at 15 kPa (20.83%) while it was only noticed at 15 kPa in the other tomato varieties. The <i>Xewel</i> and <i>Lady Nema</i> varieties obtained the smallest reductions in the number of leaves of vitroplants, with 30.79% and 27.97% at 15 kPa, respectively, and the <i>Rodeo</i> variety recorded a reduction of 35.97%. From 5 kPa, the varieties record reductions in <span>the number of secondary roots of more than 15%. The effect of osmotic pr</span>essures on decreasing the taproot height and length is not significant. The <i>Xewel </i>variety had the highest average fresh (0.483 g) and dry (0.082 g) weights of the aerial part at 15 kPa and the <i>Rodeo</i> variety </span><span style="font-family:"">had </span><span style="font-family:"">the lowest ones (0.308 g and 0.0501 g). The <i>Lady Nema</i> variety had the highest average fresh (0.171 g) and dry (0.039 g) root weights and the <i>Rodeo</i> variety</span><span style="font-family:""> had</span><span style="font-family:""> the lowest ones (0.086 and 0.020 g). The vitroplants of <i>Rodeo </i>variety recorded the highest decreases in total chlorophyll contents at all osmotic pressures and the lowest increase in proline content (53.37%) at 15 kPa. <i>A contrario</i>, the <i>Xewel</i> variety recorded the greatest increase in proline content (116.26%). Ultimately, the vitroplants of <i>Lady Nem</i>a and <i>Xewe</i>l varieties were more tolerant to water stress, the <i>Ganila </i>and<i> Mongal </i>varieties were moderately tolerant and the <i>Rodeo</i> variety was the most sensitive.
文摘The microtuber is considered one of the most effective means of spreading basic materials, as well as transporting and preserving potato germplasm varieties. To define the optimal conditions for the potato microtuber in vitro germination of Aida, Atlas and Odessa varieties, the effects of temperature, physiological age and grade (size) were evaluated. The study conducted at three different temperature levels has demonstrated that the most favorable temperature for microtuber germination at a higher and faster germination rate was 25℃, regardless of the variety. In addition, microtubers of large caliber, greater than 4 mm, germinate more quickly, with a higher germination rate, than smaller size ones (less than 4 mm) for all genotypes. For Atlas, Aida and Odessa varieties, a germination rate equal to 86.66%, 70% and 70% respectively, was obtained for microtubers with a caliber superior to 4 mm. Physiological age influences microtuber germination. The mean length of sprouts, reached after a 7 week incubation period, was more marked at “multiple sprout” and “branched sprout” stages than at a “monosprout” stage. The average length was 2.35 cm, 2.48 cm and 1.5 cm, respectively. Thus, it is necessary to plant microtubers at a “multiple sprout” stage to optimize their yield in plants and minitubers.
基金The project was funded by the International Atomic energy Agency(IAEA)under RAF5066 and RAF5076.
文摘Cowpea is one of the most important legume grains in the sub-Saharan region of Africa used for human consumption and animal feed,but its production is hampered by biotic and abiotic constraints raising the need to broaden its genetic basis.For this purpose,seeds of two cowpea varieties Melakh and Yacine were irradiated with 300 and 340 Gy of gamma-ray,respectively.The developed mutant populations were agromorphologically characterized from M5 to M7,while the genetic diversity of the latter was evaluated using 13 ISSR markers.Based on the agromorphological characterization,variation of flower color,pod length,seed coat color,and seed weight with 78.01,68.29,94.48,and 57.58%heritability,respectively,were recorded in the mutant lines.PCA analyses allowed to identify the elite mutants based on their agromorphological traits,while Pearson’s correlation results revealed a positive correlation between yield and yield component traits.Three subpopulations were identified through STRUCTURE analyses,but the assignment of the individuals in each group was improved using DAPC(Discriminant Analysis of Principal Components)analysis.Analysis of Molecular Variance revealed that the majority(85%)of the variance rather existed within groups than among(15%)groups.Finally,our study allowed us to select new promising mutant genotypes that could be tested for multi-locational trials to evaluate their agronomic performance.
文摘The residual effects of sucrose concentrations (80 or 100 g·L-1) and hormonal treatments (BAP + Kinetin or Coumarin) of tuberization medium on in vitro microtubers germination of three potato varieties (Solanum tuberosum L.) so called Aida, Atlas and Odessa, are described. After 3 weeks of incubation at 28℃ ± 1℃, 70% of Aida microtubers variety, previously formed in the MT2 medium [MS/2 + 80 g·L-1 Sucrose], germinated. The best germination rate for varieties Atlas (100%) and Odessa (66.66%) was obtained on microtubers previously formed in the medium MT2 [MS/2 + 100 g·L-1 Sucrose]. The addition of hormones in the tuberization medium allowed optimizing the microtubers germination of the Aida variety unlike the other varieties. Indeed, for the Aida variety, the combination M5 [Kin 2.5 mg·L-1 + Coum 0.025 mg·L-1 + Sucrose 80 g·L-1] increased the germination rate from 70% up to 93.33%. The best germination rate (90%), noticed with microtubers of Atlas variety, initially formed in M2 medium [Kin 1 mg·L-1 + BAP 1 mg·L-1 + Sucrose 100 g·L-1], was lower than that one (100%) obtained on medium without hormones. For Odessa variety, the maximum germination rate (53.33%) of microtubers, from the medium M4 [Kin 2.5 mg·L-1 + BAP 1 mg·L-1 + Sucrose 100 g·L-1], was also lower than that one (66.66%) observed in the medium without hormones. Aida and Atlas varieties thus offer a better germination rate than Odessa after their cold storage.
文摘Salinity is a major problem that seriously impacts agricultural production, particularly that of tomato (Solanum lycopersicum L.). However, the plant has the ability to associate with Arbuscular Mycorrhizal Fungi to better tolerate salt stress. Thus, thanks to the extension of the AMF hyphae, the hydromineral nutrition and the tolerance to excess toxic ions (Na<sup>+</sup> and Cl<sup>-</sup>) of the plant are optimized. In this context, the contribution of AMF to the salt stress tolerance of two tomato varieties under semi-controlled conditions was studied. To do this, the frequency and intensity of mycorrhization, the relative mycorrhizal dependency, the survival rates, the aerial and root dry weights, the mineral (P, K<sup>+</sup>, Na<sup>+</sup>) and proline contents of the plants subjected to four levels of salinity [0, 70, 140 and 210 mM of NaCl] were evaluated. All the parameters assessed appeared to be dependent on the variety, the fungal strain and the NaCl concentration. With the Lady Nema variety, inoculation with the Claroideoglomus etunicatum strain at [NaCl 140 mM] resulted in the highest frequencies (54%), intensities (40.47%), and relative mycorrhizal dependencies (19.65%). This same symbiotic couple recorded high survival rates (55%) and aerial (2.03 g) and root (0.50 g) dry weights. Significant contents of K<sup>+ </sup>(Leaves: 7.5 mg⋅g<sup>-1</sup>;Roots: 4.4 mg⋅g<sup>-1</sup> of dry matter), P (Leaves: 15.15 mg⋅g-1</sup> of dry matter) and proline (975 nmoles⋅g-1</sup> of fresh matter) were also recorded by this pair, with the lowest Na<sup>+</sup> contents (Leaves: 1.93 mg⋅g-1</sup>;Roots: 0.96 mg⋅g-1</sup> of dry matter). For the Mongal variety, at [NaCl 140 mM], the highest frequencies (50.36%), intensities (35.14%) and relative mycorrhizal dependencies (43.95%) were obtained thanks to inoculation with Rhizophagus fasciculatus. The highest survival rates (59%) and aerial (2.58 g) and root (0.79 g) dry weights were also obtained with this symbiotic couple. The contents of K<sup>+</sup> (Leaves: 6.1 mg⋅g-1</sup>;Roots: 3.09 mg⋅g-1 </sup>of dry matter), P (Leaves: 12.49 mg⋅g-1</sup> of dry matter) and proline (942 nmoles⋅g-1</sup> of fresh matter) the most important and those in Na<sup>+</sup> the lowest (Leaves: 2.03 mg⋅g-1</sup>;Roots: 1.53 mg⋅g-1</sup> of dry matter) were also recorded for this same pair. Thus, the best fungal partner for the Lady Nema variety is C. etunicatum, followed by F. mosseae and R. fasciculatus, while for the Mongal variety it is R. fasciculatus, followed by C. etunicatum and F. mosseae.
文摘Annona senegalensis is a savannah species present in the wild in tropical and sub-tropical African regions. It is used by the local populations for its many economic, pharmacological, nutritional and ecological interests. However, the strong pressure exerted on this species as well as the increasing degradation of the ecosystems, in which it evolves, seriously compromise its sustainability and development. Conventional methods of vegetative propagation are not sufficient to ensure its durable regeneration and the renewal of endemic populations in Senegal. In this context, it was undertaken in vitro propagation, from 30 days old juvenile seedlings. Thus, axillary, cotyledonary and apical nodes were in vitro cultured in Murashige and Skoog (1962) medium (MS), with different concentrations of cytokinins and/or auxins. BAP used alone at 2 mg•L<sup>−1</sup> proved to be more beneficial for micropropagation of different types of explants compared to Kinetin used alone or in combination with BAP, especially for axillary and cotyledonary nodes. The BAP-NAA combination allowed to have a better elongation of newly formed shoots. For shoots of apical and cotyledonary nodes origin, a rhizogenic induction of 5 days, with IBA at 25 mg•L<sup>−1</sup>, resulted in a better rooting rate with, respectively, 75% (for 2.22 roots) and 66.67% (for 4.17 roots). For newly formed shoots of axillary origin, a 24-hour rooting induction with IBA at 50 mg•L<sup>−1</sup> gave a rooting rate of 58.33% (for 2.4 roots). After 30 days of acclimatization, the survival rate was 75% for the young plants from the apices and 83.33% for those originating from the cotyledonary and axillary nodes. This protocol can therefore be adopted for the in vitro clonal propagation of A. senegalensis juvenile material.
文摘In arid and semi-arid regions, the growth and development of cultivated plants, especially tomato (Solanum lycopersicum L.), are severely limited by water deficit. Thus, to cope with this constraint, the plant establishes symbiotic relationships with arbuscular mycorrhizal fungi (AMF) in the soil whose extension of the hyphae allows a better and deeper exploration;this notably improves the hydromineral nutrition of the plant. Therefore, the choice of fungal partner becomes crucial for the establishment of a crop in water-deficient soil. In this context, the contribution of AMF to the water stress tolerance of two varieties of tomato plants was assessed under semi-controlled conditions. Parameters, such as the mycorrhizal frequency, intensity of mycorrhization, relative mycorrhizal dependency, growth, and biochemical parameters (carbon, nitrogen, phosphorus, and proline contents) of plants subjected to three levels of water stress (T100, T70, and T30), were evaluated. The highest frequencies and intensities of mycorrhization and relative mycorrhizal dependencies were obtained with plants of the Xewel variety inoculated with Rhizophagus fasciculatus (F: 95.24%, 88.35%, and 13.64%;M: 40.52%, 37.52%, and 11.22%;D: 23.7%, 54.4%, and 78.82%) and in those of the Lady Nema variety inoculated with Claroideoglomus etunicatum (F: 95.12%, 87.01%, and 15.25%;M: 40.66%, 37.99%, and 11.42%;D: 19.27%, 57.01%, and 70.98%), respectively at water regimes of T100, T70 and T30. These same symbiotic couples recorded, at T30, the best survival rates (+ 40%) and the higher aerial (77% and 74%) and root dry weights (80% and 59%). Plants of the Xewel variety inoculated with R. fasciculatus recorded the highest contents of carbon (T70: 30.59% and T30: 21.55%) and phosphorus (T70: 0.18% and T30: 0.17%). Plants of the Lady Nema variety recorded the highest nitrogen contents with 3.51% and 3.20%, respectively at T70 and T30. Plants of the Lady Nema variety, inoculated with C. etunicatum, also recorded the highest proline contents (572.25, 739.44, and 1165 nmoles•g<sup>−1</sup> of fresh material), followed by those of the Xewel variety inoculated with R. fasciculatus (580.36, 763.65, and 1112.11 nmoles•g<sup>−1</sup> of fresh matter), respectively at T100, T70, and T30. For the Lady Nema variety, the best fungal partner is C. etunicatum, followed by R. fasciculatus and, finally, Funneliformis mosseae. However, for the plants of the Xewel variety, R. fasciculatus is the most efficient, followed by F. mosseae and C. etunicatum. This suggests that, in tomatoes, the efficiency of mycorrhizal symbiosis under water stress conditions is not only dependent on the host plant but on both associated symbiotic partners. Hence, it is a need for screening to identify the best symbiotic couples in a stressful environment.
基金financially supported by the National Key Technology R&D Program of China (during the 12th Five-Year Plan Period) (2013BAD01B03-08)Agricultural Science and Technology Innovation Project of Chinese Academy of Agricultural Sciences (CAAS-ASTIP-2013-OCRI)+3 种基金the African-German Network of Excellence in Science (AGNES) for granting a Mobility Grant in 2016sponsored by German Federal Ministry of Education and Researchsupported by the Alexander von Humboldt Foundationthe Chinese Scholarship Council (2015GXY934) for a fellowship
文摘Sesame is an important oilseed crop in Africa and Asia, owing to its high nutritional quality seed and market value. Variation in sesame seed components including oil, oleic acid,linoleic acid, and protein was investigated by near-infrared reflectance spectrometry in 139 samples collected from different countries. Oil and protein contents were between 40.8%and 60.3%(mean 53.0%) and 15.5% to 25.5%(mean 20.4%), respectively. Linoleic acid,ranging from 31.8% to 52.4%(mean 46%) was more abundant than oleic acid(31.8%–50.6%,mean 38.1%). Light-seeded samples displayed higher nutritional quality, as they were richer in oil, protein, and linoleic acid than dark seeds. Samples from Africa had higher oil and linoleic acid contents, while Asian samples had higher oleic content. The analysis revealed West African sesame cultivars containing especially high levels of seed components, which may command high market values. Two clusters of sesame samples grouped by seed composition were obtained, including one cluster with high oil and oleic acid content and the other with high protein and linoleic acid content. This study revealed that sesame samples from Africa and Asia harbor high variation for major seed components and also provided background information for breeding high-nutrition varieties according to the demands of sesame seed markets.
文摘The potato (</span><i><span style="font-family:Verdana;">Solanum tuberosum</span></i><span style="font-family:Verdana;"> L.) is a vegetable that ranks fifth in the world for human consumption. Its importance is growing more and more in the Senegalese diet. However, the potato production in Senegal does not meet the needs of the market, which maintains dependence on the outside for the supply of quality seeds. In addition, these imported seeds do not often have phytosanitary qualities required for local production in the Sahelian zone. The </span><i><span style="font-family:Verdana;">in vitro </span></i><span style="font-family:Verdana;">production of microtubers, used as seed, has been shown to be one of the mos</span><span style="font-family:Verdana;">t efficient means for propagation of basic material. To overcome the constraints linked to the supply and availability of potato seeds, with high germination capacity, the impact of the microtuber size on the yield of the plants under semi-controlled conditions was examined. The pre-germinated</span><span style="font-family:Verdana;"> microtubers were produced </span><i><span style="font-family:Verdana;">in vitro </span></i><span style="font-family:Verdana;">from vitroplants of 3 different varieties (</span><i><span style="font-family:Verdana;">Aida</span></i><span style="font-family:Verdana;">,</span><i><span style="font-family:Verdana;"> Atlas</span></i><span style="font-family:Verdana;">,</span><i><span style="font-family:Verdana;"> Odessa</span></i><span style="font-family:Verdana;">) adapted to the edaphic-climatic conditions of Senegal. The effects of the seed sizes of microtubers, greater than 4 mm, sown under semi-controlled conditions, on the yield of the plants</span></span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> result in an increase in the ratio, in the vegetative development of the plants, but also in the number and size of the minitubers harvested. The yield of the plants also depends on the variety. It can therefore be envisaged to produce local potato seeds from microtubers and minitubers.
