Groundnut (Arachis hypogaea L.) is an important cash crop for smallholder farmers in western Ethiopia. However, the yield of the crop is very low mainly because of strong soil acidity and poor soil fertility managemen...Groundnut (Arachis hypogaea L.) is an important cash crop for smallholder farmers in western Ethiopia. However, the yield of the crop is very low mainly because of strong soil acidity and poor soil fertility management. A study conducted to evaluate the effect of lime and mineral phosphorus fertilizer on yield components and yield of groundnut. The treatments consisted of three phosphorus rates (0, 46 and 92 kg P<sub>2</sub>O<sub>5·</sub>ha<sup>-1</sup>), three lime rates (0, 6, and 11 ton lime·ha<sup>-1</sup>), and three groundnut varieties (local cultivar, Werer-961, and Werer-963) was laid-out as a randomized complete design in a factorial arrangement with three replications. The corresponding rates of phosphorus applied per pot of soil (7 kg) amounted to 0, 107 and 215 mg kg·soil<sup>-1</sup> and those of lime amounted to 0, 14, and 26 g kg·soil<sup>-1</sup>. The analysis of variance showed that phenological characters, yield, and yield components significantly affected by interaction of variety, phosphorus, and lime. The highest dry pod yield produced by Werer-963 (2 kg dry pod yield·pot<sup>-1</sup>) in response to the application 11 t·ha<sup>-1</sup> lime and 46 kg P<sub>2</sub>O<sub>5</sub>·ha<sup>-1</sup>. However, Werer-961 produced medium (1.5 kg dry pod yield·pot<sup>-1</sup>) at 11 t·ha<sup>-1</sup> lime and 92 kg P<sub>2</sub>O<sub>5</sub>·ha<sup>-1</sup> and the local cultivar produced minimum (1 kg dry pod yield·pot<sup>-1</sup>) at the application of 11 t·ha<sup>-1</sup> lime and 92 kg P<sub>2</sub>O<sub>5</sub>·ha<sup>-1</sup>. In terms of phosphorus yield efficiency index, Werer-963 was highly efficient (index of 1.71), and Werer-961 was moderately efficient (index of 0.6). However, the local cultivar was inefficient (index of 0.04). It is at, in acidic soil of the study area Werer-963 is the best to be cultivated with application of lime 11 t·ha<sup>-1</sup> and 46 kg P<sub>2</sub>O<sub>5</sub>·ha<sup>-1</sup> fertilizer, followed by Werer-961. The results of this pot experiment have revealed that farmers in the study area need to switch to cultivating the improved varieties of groundnut rather than local variety with the application of high rates of lime and moderate amounts of phosphorus.展开更多
Six field studies were completed in Ontario (during 2016 to 2018) to assess the tolerance of adzuki, kidney, small red and navy bean to 2,4-D ester at 528 or 1056 g·ai·ha-1 applied 14, 7 and 1 da...Six field studies were completed in Ontario (during 2016 to 2018) to assess the tolerance of adzuki, kidney, small red and navy bean to 2,4-D ester at 528 or 1056 g·ai·ha-1 applied 14, 7 and 1 day before seeding (PP) and 3 days after seeding (PRE). 2,4-D applied PP or PRE caused as much as 4%, 6%, 7% and 8% injury in adzuki, kidney, small red and navy (white) bean, respectively. There was an increase in bean injury as the preplant interval decreased. At 1 WAE, 2,4-D applied at 1056 g·ai·ha-1 14, 7 and 1 day PP and 3 days after seeding caused up to 6%, 10%, 18% and 5% visible bean injury, respectively. The level of injury decreased over time with minimal bean injury (0 to 3%) at 8 WAE. Bean stand counts were similar to the non-treated control with 2,4-D applied at various timings except at 1 day PP when 2,4-D at the 2X rate decreased bean stand 13%. There was up to 23% and 43% decrease in bean dry weight with 2,4-D applied PP at 528 and 1056 g·ai·ha-1 7 and 1 day PP, respectively. Bean height (6 WAE) was not affected by 2,4-D applied at various timings except at 1 day PP when 2,4-D (1056 g·ai·ha-1) decreased bean height 10%. Additionally, there was no effect of 2,4-D treatments on bean maturity or yield. Based on these results, the safest times to apply 2,4-D are 14 days before seeding or PRE. Injury was higher when 2,4-D was applied 7 and 1 day PP. Injury was lower in adzuki bean compared to kidney, small red or navy bean.展开更多
A 2-year field study was conducted in northern Greece to investigate the effect of nitrogen fertilization and irrigation on productivity of three Greek chickpea varieties (“Amorgos” “Serifos”, “Andros”). Chickpe...A 2-year field study was conducted in northern Greece to investigate the effect of nitrogen fertilization and irrigation on productivity of three Greek chickpea varieties (“Amorgos” “Serifos”, “Andros”). Chickpea, grown under irrigation regime (30 + 30 mm of water) and fertilized with 50 kg·N·ha-1 before planting and with 40 kg·N·ha-1 at blossom growth stage, produced more total dry biomass and seed yield as compared with that grown under non-irrigated conditions and fertilized with 50 kg·N·ha-1 before planting only. In particular, irrigation and nitrogen fertilization at blossom growth stage increased total dry weight of chickpea by 18.3% and 18.5%, respectively, as compared with that of non-irrigated and fertilized with N before planting. The corresponding increase of seed yield was 30.5% and 20%, respectively. The total dry biomass of “Amorgos” was 10% and 13% greater than that of “Serifos” and “Andros”, while its respective seed yield increase was 5% and 16%. Finally, the quantum yield of photosystem II of chickpea was not affected by irrigation or fertilization. These results indicated that nitrogen fertilization at blossom growth stage combined with irrigation increased seed yield of all chickpea varieties, whereas the same treatments did not have any effect on plant quantum yield of photosystem II.展开更多
Essential plant nutrients contained in residues and wastes generated during biofuel processing can be recovered for further production of bioenergy biomass. The objective of this study was to determine the relative ag...Essential plant nutrients contained in residues and wastes generated during biofuel processing can be recovered for further production of bioenergy biomass. The objective of this study was to determine the relative agronomic efficiency of “processed” biofuel residual (PBR). Liquid biofuel residual was “processed” by precipitating phosphate and ammonium in the residual with magnesium into a struvite-like material. Then, in a series of greenhouse experiments, we evaluated the fertility potential of PBR, using sweet sorghum (Sorghum bicolor (L.) Moench), as a test bioenergy crop. We compared the agronomic effectiveness of PBR to inorganic commercial fertilizers, biosolids, and poultry manure as nutrient sources. The sources were either applied alone or in combination with supplemental essential plant nutrients (S, K, Mg, and micronutrients). In each of the greenhouse experiments, the crop was grown for 12 wk on soil of minimal native fertility. After each harvest, sufficient water was applied to the soil in each pot over a 6-wk period to yield ~2 L (~one pore volume) of leachate to assess potential total N and soluble reactive phosphorus (SRP) losses. Dry matter yields from the PBR treatment applied alone were significantly greater than yields from inorganic fertilizers, biosolids, and poultry manure treatments applied alone, and similar to yields obtained when the supplemental essential plant nutrients were added to the inorganic fertilizer, biosolids, and manure treatments. Leachate N and SRP concentrations from the PBR treatment were significantly lower than in the treatments with inorganic fertilizers, poultry manure, and biosolids. We conclude that PBR can substitute for inorganic fertilizers and other organic sources of plant nutrients to produce bioenergy biomass cheaply, without causing offsite N and P losses in vulnerable soils.展开更多
文摘Groundnut (Arachis hypogaea L.) is an important cash crop for smallholder farmers in western Ethiopia. However, the yield of the crop is very low mainly because of strong soil acidity and poor soil fertility management. A study conducted to evaluate the effect of lime and mineral phosphorus fertilizer on yield components and yield of groundnut. The treatments consisted of three phosphorus rates (0, 46 and 92 kg P<sub>2</sub>O<sub>5·</sub>ha<sup>-1</sup>), three lime rates (0, 6, and 11 ton lime·ha<sup>-1</sup>), and three groundnut varieties (local cultivar, Werer-961, and Werer-963) was laid-out as a randomized complete design in a factorial arrangement with three replications. The corresponding rates of phosphorus applied per pot of soil (7 kg) amounted to 0, 107 and 215 mg kg·soil<sup>-1</sup> and those of lime amounted to 0, 14, and 26 g kg·soil<sup>-1</sup>. The analysis of variance showed that phenological characters, yield, and yield components significantly affected by interaction of variety, phosphorus, and lime. The highest dry pod yield produced by Werer-963 (2 kg dry pod yield·pot<sup>-1</sup>) in response to the application 11 t·ha<sup>-1</sup> lime and 46 kg P<sub>2</sub>O<sub>5</sub>·ha<sup>-1</sup>. However, Werer-961 produced medium (1.5 kg dry pod yield·pot<sup>-1</sup>) at 11 t·ha<sup>-1</sup> lime and 92 kg P<sub>2</sub>O<sub>5</sub>·ha<sup>-1</sup> and the local cultivar produced minimum (1 kg dry pod yield·pot<sup>-1</sup>) at the application of 11 t·ha<sup>-1</sup> lime and 92 kg P<sub>2</sub>O<sub>5</sub>·ha<sup>-1</sup>. In terms of phosphorus yield efficiency index, Werer-963 was highly efficient (index of 1.71), and Werer-961 was moderately efficient (index of 0.6). However, the local cultivar was inefficient (index of 0.04). It is at, in acidic soil of the study area Werer-963 is the best to be cultivated with application of lime 11 t·ha<sup>-1</sup> and 46 kg P<sub>2</sub>O<sub>5</sub>·ha<sup>-1</sup> fertilizer, followed by Werer-961. The results of this pot experiment have revealed that farmers in the study area need to switch to cultivating the improved varieties of groundnut rather than local variety with the application of high rates of lime and moderate amounts of phosphorus.
文摘Six field studies were completed in Ontario (during 2016 to 2018) to assess the tolerance of adzuki, kidney, small red and navy bean to 2,4-D ester at 528 or 1056 g·ai·ha-1 applied 14, 7 and 1 day before seeding (PP) and 3 days after seeding (PRE). 2,4-D applied PP or PRE caused as much as 4%, 6%, 7% and 8% injury in adzuki, kidney, small red and navy (white) bean, respectively. There was an increase in bean injury as the preplant interval decreased. At 1 WAE, 2,4-D applied at 1056 g·ai·ha-1 14, 7 and 1 day PP and 3 days after seeding caused up to 6%, 10%, 18% and 5% visible bean injury, respectively. The level of injury decreased over time with minimal bean injury (0 to 3%) at 8 WAE. Bean stand counts were similar to the non-treated control with 2,4-D applied at various timings except at 1 day PP when 2,4-D at the 2X rate decreased bean stand 13%. There was up to 23% and 43% decrease in bean dry weight with 2,4-D applied PP at 528 and 1056 g·ai·ha-1 7 and 1 day PP, respectively. Bean height (6 WAE) was not affected by 2,4-D applied at various timings except at 1 day PP when 2,4-D (1056 g·ai·ha-1) decreased bean height 10%. Additionally, there was no effect of 2,4-D treatments on bean maturity or yield. Based on these results, the safest times to apply 2,4-D are 14 days before seeding or PRE. Injury was higher when 2,4-D was applied 7 and 1 day PP. Injury was lower in adzuki bean compared to kidney, small red or navy bean.
文摘A 2-year field study was conducted in northern Greece to investigate the effect of nitrogen fertilization and irrigation on productivity of three Greek chickpea varieties (“Amorgos” “Serifos”, “Andros”). Chickpea, grown under irrigation regime (30 + 30 mm of water) and fertilized with 50 kg·N·ha-1 before planting and with 40 kg·N·ha-1 at blossom growth stage, produced more total dry biomass and seed yield as compared with that grown under non-irrigated conditions and fertilized with 50 kg·N·ha-1 before planting only. In particular, irrigation and nitrogen fertilization at blossom growth stage increased total dry weight of chickpea by 18.3% and 18.5%, respectively, as compared with that of non-irrigated and fertilized with N before planting. The corresponding increase of seed yield was 30.5% and 20%, respectively. The total dry biomass of “Amorgos” was 10% and 13% greater than that of “Serifos” and “Andros”, while its respective seed yield increase was 5% and 16%. Finally, the quantum yield of photosystem II of chickpea was not affected by irrigation or fertilization. These results indicated that nitrogen fertilization at blossom growth stage combined with irrigation increased seed yield of all chickpea varieties, whereas the same treatments did not have any effect on plant quantum yield of photosystem II.
文摘Essential plant nutrients contained in residues and wastes generated during biofuel processing can be recovered for further production of bioenergy biomass. The objective of this study was to determine the relative agronomic efficiency of “processed” biofuel residual (PBR). Liquid biofuel residual was “processed” by precipitating phosphate and ammonium in the residual with magnesium into a struvite-like material. Then, in a series of greenhouse experiments, we evaluated the fertility potential of PBR, using sweet sorghum (Sorghum bicolor (L.) Moench), as a test bioenergy crop. We compared the agronomic effectiveness of PBR to inorganic commercial fertilizers, biosolids, and poultry manure as nutrient sources. The sources were either applied alone or in combination with supplemental essential plant nutrients (S, K, Mg, and micronutrients). In each of the greenhouse experiments, the crop was grown for 12 wk on soil of minimal native fertility. After each harvest, sufficient water was applied to the soil in each pot over a 6-wk period to yield ~2 L (~one pore volume) of leachate to assess potential total N and soluble reactive phosphorus (SRP) losses. Dry matter yields from the PBR treatment applied alone were significantly greater than yields from inorganic fertilizers, biosolids, and poultry manure treatments applied alone, and similar to yields obtained when the supplemental essential plant nutrients were added to the inorganic fertilizer, biosolids, and manure treatments. Leachate N and SRP concentrations from the PBR treatment were significantly lower than in the treatments with inorganic fertilizers, poultry manure, and biosolids. We conclude that PBR can substitute for inorganic fertilizers and other organic sources of plant nutrients to produce bioenergy biomass cheaply, without causing offsite N and P losses in vulnerable soils.
