Drought stress has long been a major constraint in maintaining yield stability of soybean (Glycine max (L.) Merr.) in rainfed ecosystems. The identification of consistent quantitative trait loci (QTL) involving ...Drought stress has long been a major constraint in maintaining yield stability of soybean (Glycine max (L.) Merr.) in rainfed ecosystems. The identification of consistent quantitative trait loci (QTL) involving seed yield per plant (YP) and drought susceptibility index (DSI) in a population across different environments would therefore be important in molecular marker-assisted breeding of soybean cultivars suitable for rainfed regions. The YP of a recombinant line population of 184 F2:7:11 lines from a cross of Kefengl and Nannong1138-2 was studied under water-stressed (WS) and well-watered (WW) conditions in field (F) and greenhouse (G) trials, and DSI for yield was calculated in two trials. Nineteen QTLs associated with YP-WS and YP-WW, and 10 QTLs associated with DSI, were identi- fied. Comparison of these QTL locations with previous findings showed that the majority of these regions control one or more traits re- lated to yield and other agronomic traits. One QTL on molecular linkage group (MLG) K for YP-F, and two QTLs on MLG C2 for YP-G, remained constant across different water regimes. The regions on MLG C2 for YP-WW-F and MLG H for YP-WS-F had a pleiotropic effect on DSI-F, and MLG A1 for YP-WS-G had a pleiotropic effect on DSI-G. The identification of consistent QTLs for YP and DSI across different environments will significantly improve the efficiency of selecting for drought tolerance in soybean.展开更多
This study examined whether low-density co-inoculation of Myanmar Bradyrhizobium yuanmingense strain MAS34 and Streptomyces griseoflavus P4 would enhance nodulation, N2 fixation, and seed yield in two soybean varietie...This study examined whether low-density co-inoculation of Myanmar Bradyrhizobium yuanmingense strain MAS34 and Streptomyces griseoflavus P4 would enhance nodulation, N2 fixation, and seed yield in two soybean varieties. A field experiment was conducted during the July to November 2012 growing season at Kyushu University Farm, Japan, using a split-plot design with three replications and the following four treatments: T1, an uninoculated treatment with peat moss (uninoculated);T2, a single inoculation with S. griseoflavus P4 (P4);T3, a single inoculation of B. yuanmingense MAS34 (MAS34);and T4, a dual inoculation of P4 with MAS34 (P4 + MAS34). Two varieties of soybean, Yezin-3 (Rj4) and Yezin-6 (non-Rj), were used. The N2 fixation activity of soybean was evaluated by the relative ureide method using xylem solute from root bled sap at the early pod-fill stage (R3.5). Dry matter production, N2 fixation, and seed yield were significantly (P 0.01) different between the inoculated treatments. The effect of variety was also significant (P 0.05) for nodule dry weight at the V6 stage, percentage of N derived from the atmosphere at the R3.5 stage, and seed yield at the maturity stage. The number of nodules on the tap roots was significantly higher in Yezin-3 than in Yezin-6. The single inoculation of P4 did not have a significant effect on dry matter production, N2 fixation, and seed yield in either soybean variety. The dry matter production, relative ureide index, percentage of N derived from the atmosphere, and seed yield were significantly (P 0.01) enhanced by a single inoculation of MAS34 in Yezin-3 and by dual inoculation of P4 + MAS34 in Yezin-6. These results indicate that low inoculum concentrations (105 cells seed-1) increase N2 fixation and seed yield in these soybean varieties under open field conditions. Myanmar B. yuanmingense MAS34 and S. griseoflavus P4 are expected to be useful biofertilizers for soybean production.展开更多
In this greenhouse experiment, we investigated the effects of two constant groundwater levels: 10 cm groundwater level (GW-10) and 40 cm groundwater level (GW-40) and one change groundwater level, which was 40-10-40 c...In this greenhouse experiment, we investigated the effects of two constant groundwater levels: 10 cm groundwater level (GW-10) and 40 cm groundwater level (GW-40) and one change groundwater level, which was 40-10-40 cm (GW-40-10-40) on Cadmium (Cd) uptake and seed yield of Soybean plant in Cd contaminated soils (1.57 mg·kg-1). The experimental soil layer was made with gravel layer (14 cm), non-polluted soil (15 cm) and polluted soil (25 cm). The redox potential of every soil layer was measured from sowing to harvesting. The soil layer (10 – 40 cm) of GW-10 was always in reduction condition and that of GW-40 was always in oxidation condition. First 50 days of GW 40-10-40 were in oxidation and next 50 days in reduction and final 20 days again returned in oxidation condition. Soybean seed Cd concentration was significantly highest in GW-40-10-40 (1.16 ± 0.13 mg·kg-1) and lowest in GW-40 (0.81 ± 0.12 mg·kg-1). Cd concentration of stem was found significantly higher in GW-40 (1.7 ± 0.2 mg·kg-1) than GW-10 (0.91 ± 0.08 mg·kg-1) and GW-40-10-40 (1.28 ± 0.13 mg·kg-1). There was no significant difference in root Cd concentration among these 3 treatments. Main stem height of soybean plant and 100 seed weight of GW-40 were significantly higher than those of GW-10. The result revealed that, soil redox condition is an important factor for Cd uptake in soybean plant and seed yield of soybean. This study will help to manage the farming process more appropriately with the aim of minimizing uptake of Cd and other toxic metals in grain crops.展开更多
The paper reviews the factors and mechanisms involved in the regulation of seed growth,discusses the roles of source sink relationship in yield formation and effects of climate change and canopy photosynthesis on gro...The paper reviews the factors and mechanisms involved in the regulation of seed growth,discusses the roles of source sink relationship in yield formation and effects of climate change and canopy photosynthesis on groth and yield in soybean.展开更多
Flooding is an abiotic stress that impacts soybean [Glycine max (L.) Merr.] growth and reduces seed germination. Effect of flooding on soybean plant grown at different growth stage has been previously conducted and re...Flooding is an abiotic stress that impacts soybean [Glycine max (L.) Merr.] growth and reduces seed germination. Effect of flooding on soybean plant grown at different growth stage has been previously conducted and reported. However, soybean seed germination responses to flood stress are largely unknown. The objective of this study was to elucidate flooding influence on soybean seed germination after planting in the field. The research showed that seed germination rate (SGR) of each genotype, without flood stress, was significantly different and ranged between 64.7% to 84.0% and 69.0% to 90.7% while using untreated and fungicide-treated seed (P < 0.0001), respectively. Results indicated that fungicide treatment improved soybean seed survival and germination in the field. The average of SGR of high-yielding soybean group was significantly higher than those of non-high-yielding soybean (P < 0.0001). The results indicated that high-yielding trait of each genotype was correlated with seed germination and survival. Under flood stress in the field, SGR means of untreated and fungicide-treated seed significantly decreased over eight flooding treatment times (P Flooding effect on germination between untreated and fungicide-treated seed was not significantly different (P = 0.1559). Furthermore, comparing the high-yielding and flood-tolerant soybean groups showed no difference in their SGR means over eight flooding treatment times (P = 0.7687 and P = 0.8490), indicating that soybean seed germination did not depend on genotype, yield, and flood tolerance trait, and seed treated by fungicide did not increase its germination in the field under the flood stress. Hence, it is necessary to develop new soybean seed pelleting to improve seed germination in the field under flooding conditions.展开更多
A two-year study was carried out in Giza Agricultural Experiments and Research Station, Agricultural Research Center (ARC), Giza, Egypt in the 2020 and 2021 summer seasons to evaluate the relative tolerance of ten soy...A two-year study was carried out in Giza Agricultural Experiments and Research Station, Agricultural Research Center (ARC), Giza, Egypt in the 2020 and 2021 summer seasons to evaluate the relative tolerance of ten soybean genotypes for cotton leafworm infestation under field conditions. Soybean genotypes H<sub>11</sub>L<sub>145</sub>, H<sub>155</sub>, H<sub>113</sub>, H<sub>4</sub>L<sub>4</sub>, H<sub>15</sub>L<sub>17</sub>, H<sub>129</sub>, H<sub>30</sub>, H<sub>19</sub>L<sub>96</sub>, Giza 111, and Crawford were distributed in randomized complete blocks design with three replications. Soybean genotypes differed significantly for cotton leafworm at the 6<sup>th</sup>, 7<sup>th</sup>, and 8<sup>th</sup> week from sowing. Low values of cotton leafworm assemblages were recorded for H<sub>113</sub>, H<sub>4</sub>L<sub>4</sub>, H<sub>15</sub>L<sub>17</sub>, Giza 111, and H<sub>129</sub>. Low percentages of the larval survival number and weight, as well as the number of the survival of pupa were recorded by feeding on leaves of genotypes H<sub>4</sub>F<sub>4</sub>, H<sub>15</sub>L<sub>17</sub>, and Giza 111 under laboratory conditions. There were significant differences among the studied genotypes in most yield attributes in both seasons. Soybean genotypes H<sub>15</sub>L<sub>17</sub>, Giza 111, H<sub>113</sub>, H<sub>129</sub>, H<sub>19</sub>L<sub>96</sub>, and H<sub>4</sub>L<sub>4 </sub>gave higher seed yield per ha, meanwhile soybean genotypes H<sub>155</sub>, H<sub>19</sub>L<sub>96</sub>, H<sub>30</sub>, Giza 111, and H<sub>15</sub>L<sub>17</sub> had higher seed oil content than the other genotypes in both seasons. The number and weight of larvae surviving, as well as the number of pupa survival, were negatively correlated with leaf total phenols and seed oil content. It can be concluded that soybean genotypes H<sub>15</sub>L<sub>17</sub>, H<sub>4</sub>L<sub>4</sub>, and Giza 111 are promising genotypes with desirable seed oil content for tolerating cotton leafworm infestation in breeding programs.展开更多
基金supported in part by the National High-Tech Program (No.2006AA10Z1C1)National Basic Research Program (No.2004CB117206 and 2009CB118400)+2 种基金the National Natural Science Foundation of China (No.30471094)the Key Project of Science and Technology of Shanxi Province (No.051017)the Scientific Research Foundation for Youth Academic Leaders from University in Shanxi Province (No.200425)
文摘Drought stress has long been a major constraint in maintaining yield stability of soybean (Glycine max (L.) Merr.) in rainfed ecosystems. The identification of consistent quantitative trait loci (QTL) involving seed yield per plant (YP) and drought susceptibility index (DSI) in a population across different environments would therefore be important in molecular marker-assisted breeding of soybean cultivars suitable for rainfed regions. The YP of a recombinant line population of 184 F2:7:11 lines from a cross of Kefengl and Nannong1138-2 was studied under water-stressed (WS) and well-watered (WW) conditions in field (F) and greenhouse (G) trials, and DSI for yield was calculated in two trials. Nineteen QTLs associated with YP-WS and YP-WW, and 10 QTLs associated with DSI, were identi- fied. Comparison of these QTL locations with previous findings showed that the majority of these regions control one or more traits re- lated to yield and other agronomic traits. One QTL on molecular linkage group (MLG) K for YP-F, and two QTLs on MLG C2 for YP-G, remained constant across different water regimes. The regions on MLG C2 for YP-WW-F and MLG H for YP-WS-F had a pleiotropic effect on DSI-F, and MLG A1 for YP-WS-G had a pleiotropic effect on DSI-G. The identification of consistent QTLs for YP and DSI across different environments will significantly improve the efficiency of selecting for drought tolerance in soybean.
文摘This study examined whether low-density co-inoculation of Myanmar Bradyrhizobium yuanmingense strain MAS34 and Streptomyces griseoflavus P4 would enhance nodulation, N2 fixation, and seed yield in two soybean varieties. A field experiment was conducted during the July to November 2012 growing season at Kyushu University Farm, Japan, using a split-plot design with three replications and the following four treatments: T1, an uninoculated treatment with peat moss (uninoculated);T2, a single inoculation with S. griseoflavus P4 (P4);T3, a single inoculation of B. yuanmingense MAS34 (MAS34);and T4, a dual inoculation of P4 with MAS34 (P4 + MAS34). Two varieties of soybean, Yezin-3 (Rj4) and Yezin-6 (non-Rj), were used. The N2 fixation activity of soybean was evaluated by the relative ureide method using xylem solute from root bled sap at the early pod-fill stage (R3.5). Dry matter production, N2 fixation, and seed yield were significantly (P 0.01) different between the inoculated treatments. The effect of variety was also significant (P 0.05) for nodule dry weight at the V6 stage, percentage of N derived from the atmosphere at the R3.5 stage, and seed yield at the maturity stage. The number of nodules on the tap roots was significantly higher in Yezin-3 than in Yezin-6. The single inoculation of P4 did not have a significant effect on dry matter production, N2 fixation, and seed yield in either soybean variety. The dry matter production, relative ureide index, percentage of N derived from the atmosphere, and seed yield were significantly (P 0.01) enhanced by a single inoculation of MAS34 in Yezin-3 and by dual inoculation of P4 + MAS34 in Yezin-6. These results indicate that low inoculum concentrations (105 cells seed-1) increase N2 fixation and seed yield in these soybean varieties under open field conditions. Myanmar B. yuanmingense MAS34 and S. griseoflavus P4 are expected to be useful biofertilizers for soybean production.
文摘In this greenhouse experiment, we investigated the effects of two constant groundwater levels: 10 cm groundwater level (GW-10) and 40 cm groundwater level (GW-40) and one change groundwater level, which was 40-10-40 cm (GW-40-10-40) on Cadmium (Cd) uptake and seed yield of Soybean plant in Cd contaminated soils (1.57 mg·kg-1). The experimental soil layer was made with gravel layer (14 cm), non-polluted soil (15 cm) and polluted soil (25 cm). The redox potential of every soil layer was measured from sowing to harvesting. The soil layer (10 – 40 cm) of GW-10 was always in reduction condition and that of GW-40 was always in oxidation condition. First 50 days of GW 40-10-40 were in oxidation and next 50 days in reduction and final 20 days again returned in oxidation condition. Soybean seed Cd concentration was significantly highest in GW-40-10-40 (1.16 ± 0.13 mg·kg-1) and lowest in GW-40 (0.81 ± 0.12 mg·kg-1). Cd concentration of stem was found significantly higher in GW-40 (1.7 ± 0.2 mg·kg-1) than GW-10 (0.91 ± 0.08 mg·kg-1) and GW-40-10-40 (1.28 ± 0.13 mg·kg-1). There was no significant difference in root Cd concentration among these 3 treatments. Main stem height of soybean plant and 100 seed weight of GW-40 were significantly higher than those of GW-10. The result revealed that, soil redox condition is an important factor for Cd uptake in soybean plant and seed yield of soybean. This study will help to manage the farming process more appropriately with the aim of minimizing uptake of Cd and other toxic metals in grain crops.
文摘The paper reviews the factors and mechanisms involved in the regulation of seed growth,discusses the roles of source sink relationship in yield formation and effects of climate change and canopy photosynthesis on groth and yield in soybean.
文摘Flooding is an abiotic stress that impacts soybean [Glycine max (L.) Merr.] growth and reduces seed germination. Effect of flooding on soybean plant grown at different growth stage has been previously conducted and reported. However, soybean seed germination responses to flood stress are largely unknown. The objective of this study was to elucidate flooding influence on soybean seed germination after planting in the field. The research showed that seed germination rate (SGR) of each genotype, without flood stress, was significantly different and ranged between 64.7% to 84.0% and 69.0% to 90.7% while using untreated and fungicide-treated seed (P < 0.0001), respectively. Results indicated that fungicide treatment improved soybean seed survival and germination in the field. The average of SGR of high-yielding soybean group was significantly higher than those of non-high-yielding soybean (P < 0.0001). The results indicated that high-yielding trait of each genotype was correlated with seed germination and survival. Under flood stress in the field, SGR means of untreated and fungicide-treated seed significantly decreased over eight flooding treatment times (P Flooding effect on germination between untreated and fungicide-treated seed was not significantly different (P = 0.1559). Furthermore, comparing the high-yielding and flood-tolerant soybean groups showed no difference in their SGR means over eight flooding treatment times (P = 0.7687 and P = 0.8490), indicating that soybean seed germination did not depend on genotype, yield, and flood tolerance trait, and seed treated by fungicide did not increase its germination in the field under the flood stress. Hence, it is necessary to develop new soybean seed pelleting to improve seed germination in the field under flooding conditions.
文摘A two-year study was carried out in Giza Agricultural Experiments and Research Station, Agricultural Research Center (ARC), Giza, Egypt in the 2020 and 2021 summer seasons to evaluate the relative tolerance of ten soybean genotypes for cotton leafworm infestation under field conditions. Soybean genotypes H<sub>11</sub>L<sub>145</sub>, H<sub>155</sub>, H<sub>113</sub>, H<sub>4</sub>L<sub>4</sub>, H<sub>15</sub>L<sub>17</sub>, H<sub>129</sub>, H<sub>30</sub>, H<sub>19</sub>L<sub>96</sub>, Giza 111, and Crawford were distributed in randomized complete blocks design with three replications. Soybean genotypes differed significantly for cotton leafworm at the 6<sup>th</sup>, 7<sup>th</sup>, and 8<sup>th</sup> week from sowing. Low values of cotton leafworm assemblages were recorded for H<sub>113</sub>, H<sub>4</sub>L<sub>4</sub>, H<sub>15</sub>L<sub>17</sub>, Giza 111, and H<sub>129</sub>. Low percentages of the larval survival number and weight, as well as the number of the survival of pupa were recorded by feeding on leaves of genotypes H<sub>4</sub>F<sub>4</sub>, H<sub>15</sub>L<sub>17</sub>, and Giza 111 under laboratory conditions. There were significant differences among the studied genotypes in most yield attributes in both seasons. Soybean genotypes H<sub>15</sub>L<sub>17</sub>, Giza 111, H<sub>113</sub>, H<sub>129</sub>, H<sub>19</sub>L<sub>96</sub>, and H<sub>4</sub>L<sub>4 </sub>gave higher seed yield per ha, meanwhile soybean genotypes H<sub>155</sub>, H<sub>19</sub>L<sub>96</sub>, H<sub>30</sub>, Giza 111, and H<sub>15</sub>L<sub>17</sub> had higher seed oil content than the other genotypes in both seasons. The number and weight of larvae surviving, as well as the number of pupa survival, were negatively correlated with leaf total phenols and seed oil content. It can be concluded that soybean genotypes H<sub>15</sub>L<sub>17</sub>, H<sub>4</sub>L<sub>4</sub>, and Giza 111 are promising genotypes with desirable seed oil content for tolerating cotton leafworm infestation in breeding programs.