Casamance was perceived as an agricultural granary that had rice potential which could meet the high food demand of Senegal. Given that the rice-growing lands have been degraded due to pedoclimatic variabilities, impr...Casamance was perceived as an agricultural granary that had rice potential which could meet the high food demand of Senegal. Given that the rice-growing lands have been degraded due to pedoclimatic variabilities, improved modern varieties are not usually well adapted to the Casamance rice-growing ecosystems. This work aims to contribute to the increase of rice production through varietal diversification and enhancement of cultural heritage. A participatory evaluation of five local farmers’ traditional varieties along with one check was carried out in an experiment laid out in a one-factor complete randomized block design using the six accessions with five replications. ANOVA followed by a 5% mean comparison Tukey test and the Kendall Rate were performed with IBM SPSS Statistics software. The result showed very significant varietal differences for leaf blade of the penultimate leaves, 100-grains weight, panicle length, growth cycle, plant height, ramification of secondary branching of the spikelets, resistance to lodging and threshing facility (p ≤ 0.005). However, traits including flag leaf, tiller numbers, sterile tillers number, panicle numbers, panicle yield, and grain yield did not show a significant difference (p ≥ 0.06) among varieties. Thus, based on some of these characteristics, farmers selected their most preferred rice varieties or accessions. The most important characteristics were tillering ability, lodging resistance and fertility rate. Koussik Emandiouck selected by farmers as the best variety, had a high grain yield (4.9 t∙ha<sup>-1</sup>), higher lodging resistance (9), and higher fertility rate (80.53%). Koussik Emandiouck, Koufekeny and Awandiaho varieties were the most preferred by farmers.展开更多
Until recently,potassium(K)has not received considerable attention because of the general belief that soils contain ample amounts of this element.In addition,low rates of K fertilizer application in agriculture have l...Until recently,potassium(K)has not received considerable attention because of the general belief that soils contain ample amounts of this element.In addition,low rates of K fertilizer application in agriculture have led to rapid depletion of K in the rhizosphere soil in many underdeveloped countries.This results in various negative impacts,including preventing optimum utilization of applied nitrogen and phosphorus fertilizers.To compensate for these losses,massive use of K fertilizers in agriculture has been suggested.Potassium fertilizers are manufactured from rock minerals,particularly sylvite(KCl)and carnallite(KCl·MgCl2·6H2O).Unfortunately,to date,there is no cost-effective technology available for converting rock minerals into potassic fertilizers.Potassium-solubilizing microorganisms(KSMs)can release K from soil/minerals into plant-available forms,which could be a sustainable option.The possibility of using KSMs as efficient biofertilizers to improve crop production has been increasingly highlighted by researchers.In this review,the existing forms of K in soils and their availability and dynamic equilibrium are discussed.In addition,different K fertilizers and their advantages and disadvantages for crops are described.Furthermore,the microorganisms usually reported as K solubilizers,the research progress on KSMs,and future insights on the use of these KSMs in agriculture are reviewed.Screening and analyses of the published literature show that organic acid production is the common mechanism of K solubilization by bacteria and fungi.This review may serve as a proposal for the future research avenues identified here.展开更多
文摘Casamance was perceived as an agricultural granary that had rice potential which could meet the high food demand of Senegal. Given that the rice-growing lands have been degraded due to pedoclimatic variabilities, improved modern varieties are not usually well adapted to the Casamance rice-growing ecosystems. This work aims to contribute to the increase of rice production through varietal diversification and enhancement of cultural heritage. A participatory evaluation of five local farmers’ traditional varieties along with one check was carried out in an experiment laid out in a one-factor complete randomized block design using the six accessions with five replications. ANOVA followed by a 5% mean comparison Tukey test and the Kendall Rate were performed with IBM SPSS Statistics software. The result showed very significant varietal differences for leaf blade of the penultimate leaves, 100-grains weight, panicle length, growth cycle, plant height, ramification of secondary branching of the spikelets, resistance to lodging and threshing facility (p ≤ 0.005). However, traits including flag leaf, tiller numbers, sterile tillers number, panicle numbers, panicle yield, and grain yield did not show a significant difference (p ≥ 0.06) among varieties. Thus, based on some of these characteristics, farmers selected their most preferred rice varieties or accessions. The most important characteristics were tillering ability, lodging resistance and fertility rate. Koussik Emandiouck selected by farmers as the best variety, had a high grain yield (4.9 t∙ha<sup>-1</sup>), higher lodging resistance (9), and higher fertility rate (80.53%). Koussik Emandiouck, Koufekeny and Awandiaho varieties were the most preferred by farmers.
文摘Until recently,potassium(K)has not received considerable attention because of the general belief that soils contain ample amounts of this element.In addition,low rates of K fertilizer application in agriculture have led to rapid depletion of K in the rhizosphere soil in many underdeveloped countries.This results in various negative impacts,including preventing optimum utilization of applied nitrogen and phosphorus fertilizers.To compensate for these losses,massive use of K fertilizers in agriculture has been suggested.Potassium fertilizers are manufactured from rock minerals,particularly sylvite(KCl)and carnallite(KCl·MgCl2·6H2O).Unfortunately,to date,there is no cost-effective technology available for converting rock minerals into potassic fertilizers.Potassium-solubilizing microorganisms(KSMs)can release K from soil/minerals into plant-available forms,which could be a sustainable option.The possibility of using KSMs as efficient biofertilizers to improve crop production has been increasingly highlighted by researchers.In this review,the existing forms of K in soils and their availability and dynamic equilibrium are discussed.In addition,different K fertilizers and their advantages and disadvantages for crops are described.Furthermore,the microorganisms usually reported as K solubilizers,the research progress on KSMs,and future insights on the use of these KSMs in agriculture are reviewed.Screening and analyses of the published literature show that organic acid production is the common mechanism of K solubilization by bacteria and fungi.This review may serve as a proposal for the future research avenues identified here.
