A 40-day gnotobiotic microcosm experiment was carried out to quantify the effect of hastenal-feeding nematode on plant growth and nutrient absorption. The results showed that inoculation of bacterial-feeding nematode ...A 40-day gnotobiotic microcosm experiment was carried out to quantify the effect of hastenal-feeding nematode on plant growth and nutrient absorption. The results showed that inoculation of bacterial-feeding nematode Protorhabditis sp. stimulated the growth of wheat (Triticum aestivum) and the uptake of N. By the end of the 40-day incubation wheat biomass and N uptake in the treatment with nematode and bacteria (Pseudomonas sp.) increased by 6.5% and 5.9%, respectively, compared with bacteria alone treatment. The presence of nematode mainly accelerated the growth of aboveground of wheat, while it slightly inhibited the root development. There was little difference in plant tissue N concentration between treatments. P concentration and uptake of wheat, however, were generally reduced by nematode. It appears that the enhancement of plant growth and nitrogen uptake is attributed to the enhancement of nitrogen mineralization induced by nematode feeding on bacteria, and the reduction of phosphorous uptake is the result of weak root status and competition by bacteria immobilization.展开更多
Liquid pig manure (LPM), digested from pig slurry, has been used as a nutrient source substituting chemical fertilizer (CF) for some crops. This experiment was conducted to evaluate the effect of different levels of C...Liquid pig manure (LPM), digested from pig slurry, has been used as a nutrient source substituting chemical fertilizer (CF) for some crops. This experiment was conducted to evaluate the effect of different levels of CF and LPM in early July on nitrogen (N) uptake of pot-grown young “Fuyu” persimmon (Diospyros kaki). The total N and potassium (K) from CF and LPM applied to a 3 L pot were 1.2 g N and 1.15 g K for the low and 2.4 g N and 2.3 g K for the high level. From 2 weeks after the applications, secondary shoots started to grow for the CF but none for the LPM. Two nutrient sources did not significantly affect the amount of N increase in different tree parts from July 1 to August 6. At the high level, tree total N increased by 80% from 551 mg for the CF and by 31% from 583 mg for the LPM. The nutrient sources did not affect soil pH. The soil that received LPM contained more organic matter (P = 0.048), available phosphorus (P) (P = 0.002), and exchangeable K+ (P = 0.001) and Mg2+ (P = 0.009) than the soil that received CF on August 6. These results indicated that N in LPM becomes available later but its effect is more durable than CF.展开更多
The effective utilization of steel slag, a byproduct produced in large quantities from the steel refining process, is an important issue. Because steel slag contains abundant mineral components, the effects of steel s...The effective utilization of steel slag, a byproduct produced in large quantities from the steel refining process, is an important issue. Because steel slag contains abundant mineral components, the effects of steel slag on soil bacterial biomass and plant mineral uptake were analyzed in this study. The soil pH increased in proportion to the amount of steel slag added. A lower concentration (0.2% to 1%) of steel slag addition did not change the bacterial biomass. However, a higher concentration of steel slag (above 1%) had a negative effect on bacterial biomass. A lower amount of steel slag (0.2% to 1%) addition in soil leads to increased mineral (Ca, Mg, and Fe) uptake and plant growth in Brassica rapa var. periviridis and Spinacia oleracea L. However, mineral uptake by the plants decreased when a large amount of steel slag (above 1%) was added to the soil. Low concentrations of steel slag (0.2% to 1%) in soil had positive effects on plant growth, mineral uptake of plants, and bacterial biomass.展开更多
The spatial distributions of the effective nitrogen and phosphorus possess great heterogeneity in forest soil, which results in unbalance supply of introgen and phosphorus for the rhizosphere of forest trees. In this ...The spatial distributions of the effective nitrogen and phosphorus possess great heterogeneity in forest soil, which results in unbalance supply of introgen and phosphorus for the rhizosphere of forest trees. In this resent paper,unbalance supply of nitrogen and phosphorus was applied to Fraxinus mandshurica seedlings, and we studied the uptake of nitrogen and phosphorus,growth response,and the ability to integrate nitrogen and phosphorus resources of these seedlings.Our results showed that total amount of nitrogen and phosphorus in an individual seedling supplied with balanced nitrogen and phosphorus was significantly higher than that in an individual seedling supplied with unbalanced nitrogen and phosphorus.Nitrogen concentration in leaves of nitrogen-deficient seedlings was significantly lower than that in leaves of nitrogen-enough seedlings.Nitrogen deficiency increased specific leaf area.Unbalance supply of nitrogen and phosphorus reduced biomass partitioning to leaves and increased biomass partitioning to roots.Total biomass of seedlings supplied with balanced nitrogen and phosphorus was significantly higher than that of seedlings supplied with unbalanced nitrogen and phosphorus,suggesting that F. mandshurica seedlings don’t have ability to integrate nitrogen and phosphorus resources.展开更多
基金Project (No. 39570134 and 39970419) supported by the National Natural Science Foundation of China.
文摘A 40-day gnotobiotic microcosm experiment was carried out to quantify the effect of hastenal-feeding nematode on plant growth and nutrient absorption. The results showed that inoculation of bacterial-feeding nematode Protorhabditis sp. stimulated the growth of wheat (Triticum aestivum) and the uptake of N. By the end of the 40-day incubation wheat biomass and N uptake in the treatment with nematode and bacteria (Pseudomonas sp.) increased by 6.5% and 5.9%, respectively, compared with bacteria alone treatment. The presence of nematode mainly accelerated the growth of aboveground of wheat, while it slightly inhibited the root development. There was little difference in plant tissue N concentration between treatments. P concentration and uptake of wheat, however, were generally reduced by nematode. It appears that the enhancement of plant growth and nitrogen uptake is attributed to the enhancement of nitrogen mineralization induced by nematode feeding on bacteria, and the reduction of phosphorous uptake is the result of weak root status and competition by bacteria immobilization.
文摘Liquid pig manure (LPM), digested from pig slurry, has been used as a nutrient source substituting chemical fertilizer (CF) for some crops. This experiment was conducted to evaluate the effect of different levels of CF and LPM in early July on nitrogen (N) uptake of pot-grown young “Fuyu” persimmon (Diospyros kaki). The total N and potassium (K) from CF and LPM applied to a 3 L pot were 1.2 g N and 1.15 g K for the low and 2.4 g N and 2.3 g K for the high level. From 2 weeks after the applications, secondary shoots started to grow for the CF but none for the LPM. Two nutrient sources did not significantly affect the amount of N increase in different tree parts from July 1 to August 6. At the high level, tree total N increased by 80% from 551 mg for the CF and by 31% from 583 mg for the LPM. The nutrient sources did not affect soil pH. The soil that received LPM contained more organic matter (P = 0.048), available phosphorus (P) (P = 0.002), and exchangeable K+ (P = 0.001) and Mg2+ (P = 0.009) than the soil that received CF on August 6. These results indicated that N in LPM becomes available later but its effect is more durable than CF.
文摘The effective utilization of steel slag, a byproduct produced in large quantities from the steel refining process, is an important issue. Because steel slag contains abundant mineral components, the effects of steel slag on soil bacterial biomass and plant mineral uptake were analyzed in this study. The soil pH increased in proportion to the amount of steel slag added. A lower concentration (0.2% to 1%) of steel slag addition did not change the bacterial biomass. However, a higher concentration of steel slag (above 1%) had a negative effect on bacterial biomass. A lower amount of steel slag (0.2% to 1%) addition in soil leads to increased mineral (Ca, Mg, and Fe) uptake and plant growth in Brassica rapa var. periviridis and Spinacia oleracea L. However, mineral uptake by the plants decreased when a large amount of steel slag (above 1%) was added to the soil. Low concentrations of steel slag (0.2% to 1%) in soil had positive effects on plant growth, mineral uptake of plants, and bacterial biomass.
基金国家自然科学基金资助项目(30370828)The Fed-eral Ministry for Economic Cooperation and Development+1 种基金Germany (BMZ) through a Project withthe International Rice ResearchInsti-tute(IRRI)江苏省农业综合开发科技推广项目(5110614)。
文摘The spatial distributions of the effective nitrogen and phosphorus possess great heterogeneity in forest soil, which results in unbalance supply of introgen and phosphorus for the rhizosphere of forest trees. In this resent paper,unbalance supply of nitrogen and phosphorus was applied to Fraxinus mandshurica seedlings, and we studied the uptake of nitrogen and phosphorus,growth response,and the ability to integrate nitrogen and phosphorus resources of these seedlings.Our results showed that total amount of nitrogen and phosphorus in an individual seedling supplied with balanced nitrogen and phosphorus was significantly higher than that in an individual seedling supplied with unbalanced nitrogen and phosphorus.Nitrogen concentration in leaves of nitrogen-deficient seedlings was significantly lower than that in leaves of nitrogen-enough seedlings.Nitrogen deficiency increased specific leaf area.Unbalance supply of nitrogen and phosphorus reduced biomass partitioning to leaves and increased biomass partitioning to roots.Total biomass of seedlings supplied with balanced nitrogen and phosphorus was significantly higher than that of seedlings supplied with unbalanced nitrogen and phosphorus,suggesting that F. mandshurica seedlings don’t have ability to integrate nitrogen and phosphorus resources.
