Soybean （Glycine max： Fabaceae） is a mycotrophic （mycorrhizal） crop grown commercially for human consumption. Seven different fertilizer mixtures, namely cow dung, coir dust, mush room medium waste, saw dust, com...Soybean （Glycine max： Fabaceae） is a mycotrophic （mycorrhizal） crop grown commercially for human consumption. Seven different fertilizer mixtures, namely cow dung, coir dust, mush room medium waste, saw dust, compost, decaying leaves and field soil with standard dose of NPK （control） were used for this experiment. The variety used was PM 25. Soil microbial activity was measured using CO2 evolution method. The experiment was carried out as a complete randomized block design with five replicates at the rate of eight plants per replicate. Average number of leaves on 25-day and 45-day old plants, shoot-length, root-length, number of pods per plant, wet weight of pod per plant, dry weight of pod per plant, plant wet weight, plant dry weight and seed dry weight per pod were measured. All management practices were conducted according to recommendations of the Department of Agriculture from seed germination to harvesting. Data were analyzed using SAS program （9.1.3）. Highest number of pods/plant （100, 124, 102, 106） and dry-seed-weight in g/plant （12, 14.8, 12, 12） were recorded in those grown in cow dung, compost, decaying leaves and inorganic mixture （control） whereas the lowest pod production （8.7 pods/plant） and seed dry weight （1.0 g/plant） was recorded in saw dust. Instead of inorganic fertilizer there is possibility to use organic potting mixtures like compost and decaying leaves which gave a significant difference in crop productivity as compared to other treatments. Significantly highest mean microbial activity was observed in potting media filled with coir dust.展开更多
Biochar effects on legume growth and biological nitrogen fixation have been studied extensively, mostly in acidic soils with laboratory produced biochar. In the present study, a pot experiment in a full factorial expe...Biochar effects on legume growth and biological nitrogen fixation have been studied extensively, mostly in acidic soils with laboratory produced biochar. In the present study, a pot experiment in a full factorial experimental design was performed to examine soybean yield and nodulation of three genotypes grown with or without biochar and NPK fertilizers in an alkaline soil. We observed synergistic effects of biochar and NPK fertilizer applications on biomass and seed yields for all three soybean genotypes. Total biomass production and seed yield increased on average by 67% and 54%, respectively, with biochar and by 201% and 182% with NPK fertilizer application compared to the control. When applications of biochar and NPK fertilizer were combined, the increases were 391% and367%, respectively. However, the biomass production in the control was very low(692 kg ha-1) due to a high soil p H(8.80). The nodulation increased with biochar and NPK fertilizer applications, and was largest with the combined application. A correlation was found between leaf chlorophyll content(single photon avalanche diode value) and nodule number. We suggested that the synergistic increase in yield was due to a decrease in soil p H caused by biochar and NPK fertilizer applications thereby increasing P availability in this alkaline soil.展开更多
文摘Soybean （Glycine max： Fabaceae） is a mycotrophic （mycorrhizal） crop grown commercially for human consumption. Seven different fertilizer mixtures, namely cow dung, coir dust, mush room medium waste, saw dust, compost, decaying leaves and field soil with standard dose of NPK （control） were used for this experiment. The variety used was PM 25. Soil microbial activity was measured using CO2 evolution method. The experiment was carried out as a complete randomized block design with five replicates at the rate of eight plants per replicate. Average number of leaves on 25-day and 45-day old plants, shoot-length, root-length, number of pods per plant, wet weight of pod per plant, dry weight of pod per plant, plant wet weight, plant dry weight and seed dry weight per pod were measured. All management practices were conducted according to recommendations of the Department of Agriculture from seed germination to harvesting. Data were analyzed using SAS program （9.1.3）. Highest number of pods/plant （100, 124, 102, 106） and dry-seed-weight in g/plant （12, 14.8, 12, 12） were recorded in those grown in cow dung, compost, decaying leaves and inorganic mixture （control） whereas the lowest pod production （8.7 pods/plant） and seed dry weight （1.0 g/plant） was recorded in saw dust. Instead of inorganic fertilizer there is possibility to use organic potting mixtures like compost and decaying leaves which gave a significant difference in crop productivity as compared to other treatments. Significantly highest mean microbial activity was observed in potting media filled with coir dust.
基金Patuakhali Science and Technology University (PSTU),Bangladesh for funding of project
文摘Biochar effects on legume growth and biological nitrogen fixation have been studied extensively, mostly in acidic soils with laboratory produced biochar. In the present study, a pot experiment in a full factorial experimental design was performed to examine soybean yield and nodulation of three genotypes grown with or without biochar and NPK fertilizers in an alkaline soil. We observed synergistic effects of biochar and NPK fertilizer applications on biomass and seed yields for all three soybean genotypes. Total biomass production and seed yield increased on average by 67% and 54%, respectively, with biochar and by 201% and 182% with NPK fertilizer application compared to the control. When applications of biochar and NPK fertilizer were combined, the increases were 391% and367%, respectively. However, the biomass production in the control was very low(692 kg ha-1) due to a high soil p H(8.80). The nodulation increased with biochar and NPK fertilizer applications, and was largest with the combined application. A correlation was found between leaf chlorophyll content(single photon avalanche diode value) and nodule number. We suggested that the synergistic increase in yield was due to a decrease in soil p H caused by biochar and NPK fertilizer applications thereby increasing P availability in this alkaline soil.
