The effects of peanut intercropped with five different gramineous species with different phyto-siderophore release rate on iron nutrition of peanut were studied in field experiment. The rate of phyto-siderophore relea...The effects of peanut intercropped with five different gramineous species with different phyto-siderophore release rate on iron nutrition of peanut were studied in field experiment. The rate of phyto-siderophore release of five gramineous species was as following: barley>oats>wheat>>maize>sorghum. The results showed that intercropping of peanut with five gramineous species could improve iron nutrition of peanut respectively. This indicated that root exudates, especially for phytosiderophore of gramineous plants played an important role in improvement of iron nutrition of peanut. Although phytosiderophore release rates of maize and sorghum were lower than those of barley, oats and wheat, the five gramineous species had the same effects on iron improvement of peanut. The less phytosiderophore release of maize was enough to improve iron nutrition of peanut in intercropping system. For every intercropping system, intercropping model I ( the ratio of gramineous plants : peanut : gramineous plants was 2 : 3:2) was much better in improvement of iron nutrition of peanut than that of intercropping model I (the ratio of gramineous plants : peanut: gramineous plants was 2: 6:2). This led to have greater rhizosphere effect of gramineous plants on iron nutrition of peanut in intercropping model I than intercropping model I .展开更多
Abstract: A split-root system was used to investigate whether the external or internal P concentration controls root cluster formation and citrate exudation in white lupin (Lupinus albus L.) grown under controlled con...Abstract: A split-root system was used to investigate whether the external or internal P concentration controls root cluster formation and citrate exudation in white lupin (Lupinus albus L.) grown under controlled conditions. In spite of low P concentrations in the shoots and roots of the -P plant, its dry weight was not reduced compared with the +P plant. Supplying external P (0.25 mmol/L) to one root half resulted in an increase in P concentration not only in the shoot, but also in the P-deprived root half, indicating P cycling within the plants. Omitting P from both split-root pots stimulated root cluster formation in both root halves, whereas P supply to one root half stimulated root cluster formation at the beginning of the treatment. Neither P supply to just one root half continuously nor resupply of P to one root half after 19 d of P starvation inhibited root cluster formation on the P-deprived side, although the concentration of P in this root half and shoot increased markedly. The results indicate that root cluster formation in L. albus is controlled by both shoot and root P concentrations. The rates of citrate exudation by both root halves with P deficiency were higher than those of the one root half supplied with P only. In the treatment with one root half supplied with P, the rates of citrate exudation by either the P-supplied or -deprived root halves were almost the same, regardless of P concentration in the roots. The results suggest that internal P concentration controls root cluster formation and citrate exudation in white lupin, but these processes may be regulated by different mechanisms.展开更多
文摘The effects of peanut intercropped with five different gramineous species with different phyto-siderophore release rate on iron nutrition of peanut were studied in field experiment. The rate of phyto-siderophore release of five gramineous species was as following: barley>oats>wheat>>maize>sorghum. The results showed that intercropping of peanut with five gramineous species could improve iron nutrition of peanut respectively. This indicated that root exudates, especially for phytosiderophore of gramineous plants played an important role in improvement of iron nutrition of peanut. Although phytosiderophore release rates of maize and sorghum were lower than those of barley, oats and wheat, the five gramineous species had the same effects on iron improvement of peanut. The less phytosiderophore release of maize was enough to improve iron nutrition of peanut in intercropping system. For every intercropping system, intercropping model I ( the ratio of gramineous plants : peanut : gramineous plants was 2 : 3:2) was much better in improvement of iron nutrition of peanut than that of intercropping model I (the ratio of gramineous plants : peanut: gramineous plants was 2: 6:2). This led to have greater rhizosphere effect of gramineous plants on iron nutrition of peanut in intercropping model I than intercropping model I .
基金the Ministry of Education Grant for Ph.D Program，国家重点基础研究发展计划(973计划)
文摘Abstract: A split-root system was used to investigate whether the external or internal P concentration controls root cluster formation and citrate exudation in white lupin (Lupinus albus L.) grown under controlled conditions. In spite of low P concentrations in the shoots and roots of the -P plant, its dry weight was not reduced compared with the +P plant. Supplying external P (0.25 mmol/L) to one root half resulted in an increase in P concentration not only in the shoot, but also in the P-deprived root half, indicating P cycling within the plants. Omitting P from both split-root pots stimulated root cluster formation in both root halves, whereas P supply to one root half stimulated root cluster formation at the beginning of the treatment. Neither P supply to just one root half continuously nor resupply of P to one root half after 19 d of P starvation inhibited root cluster formation on the P-deprived side, although the concentration of P in this root half and shoot increased markedly. The results indicate that root cluster formation in L. albus is controlled by both shoot and root P concentrations. The rates of citrate exudation by both root halves with P deficiency were higher than those of the one root half supplied with P only. In the treatment with one root half supplied with P, the rates of citrate exudation by either the P-supplied or -deprived root halves were almost the same, regardless of P concentration in the roots. The results suggest that internal P concentration controls root cluster formation and citrate exudation in white lupin, but these processes may be regulated by different mechanisms.
