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Stretchable electrodes are critical to the development of advanced technologies such as human–machine interaction, flexible sensing, and wearable power supply, making them of significant research value. However, the current preparation methods for high‐performance stretchable electrodes are complex and inefficient, posing challenges for their large‐scale application in the realm of flexible wearables. To address this need, a straightforward and efficient embedding strategy is reported for fabricating stretchable silver nanowire/thermoplastic elastomer composite electrodes (referred to as Strem‐AT) utilizing the viscoelasticity and outstanding mechanical properties of polymer elastomers to achieve outstanding extensibility, conductivity, and a smooth surface. These electrodes exhibit excellent tensile behavior, low surface roughness, and stable electrical properties, enabling their successful integration into stretchable sensors and intrinsically stretchable organic photovoltaic cells (IS‐OPV). When applied to human skin joints for motion detection, the sensor demonstrates remarkable stretchability and stable signal output. Importantly, the all‐polymer IS‐OPV exhibits a top‐notch power conversion efficiency (PCE) of >12.5% and a PCE80% strain exceeding 50%. Furthermore, even after subjecting high‐strain stretching at 50% for 1000 cycles, the IS‐OPV can retain 76% of the initial PCE. This study presents a multifunctional stretchable electrode with high repeatability and easy‐to‐scale fabrication in wearable sensors and photovoltaics. [ABSTRACT FROM AUTHOR]

It is unclear how elevated CO2 (eCO2) and warming interactively influence soil N mineralization in the rhizosphere of rice (Oryza sativa L.), given that the N mineralization process in anaerobic paddy soils differs from that of aerobic upland soils. In this study, we conducted a rhizobox experiment in open top chambers and used 15N-13C dual-labeling to examine the impacts of eCO2 (700 ppm) and warming (2 °C above the ambient) on N mineralization and associated microbial processes in the rhizosphere of rice plants under anaerobic conditions. Compared to the control, the combination of eCO2 and warming increased rice N uptake by 50% in a no-added-N treatment and 32% under an N-added treatment, with the additional uptake mainly consisting of soil-derived N. Co-elevation of CO2 and temperature increased microbial biomass C and N and increased N mineralization by 41% and 23% in the no-added-N and N-added treatments, respectively. The absolute abundances of the N-mineralization genes chiA, pepA, pepN, and urea hydrolysis gene ureC in the rhizosphere increased by 22–30% under eCO2 and warming, corresponding to the additional N mineralization and photosynthetic C allocation into the soil. However, eCO2 plus warming did not increase the metabolic efficiency of N mineralization (mineralized N per unit microbial N). Our results suggest that the co-elevation of CO2 and temperature stimulated microbially mediated soil N mineralization in the rhizosphere of rice, posing a risk on the acceleration of soil organic matter decomposition. [ABSTRACT FROM AUTHOR]

Phytophthora root rot is a devastating disease of soybean caused by Phytophthora sojae. However, the resistance mechanism is not yet clear. Our previous studies have shown that GmAP2 enhances sensitivity to P. sojae in soybean, and GmMYB78 is downregulated in the transcriptome analysis of GmAP2-overexpressing transgenic hairy roots. Here, GmMYB78 was significantly induced by P. sojae in susceptible soybean, and the overexpressing of GmMYB78 enhanced sensitivity to the pathogen, while silencing GmMYB78 enhances resistance to P. sojae, indicating that GmMYB78 is a negative regulator of P. sojae. Moreover, the jasmonic acid (JA) content and JA synthesis gene GmAOS1 was highly upregulated in GmMYB78-silencing roots and highly downregulated in overexpressing ones, suggesting that GmMYB78 could respond to P. sojae through the JA signaling pathway. Furthermore, the expression of several pathogenesis-related genes was significantly lower in GmMYB78-overexpressing roots and higher in GmMYB78-silencing ones. Additionally, we screened and identified the upstream regulator GmbHLH122 and downstream target gene GmbZIP25 of GmMYB78. GmbHLH122 was highly induced by P. sojae and could inhibit GmMYB78 expression in resistant soybean, and GmMYB78 was highly expressed to activate downstream target gene GmbZIP25 transcription in susceptible soybean. In conclusion, our data reveal that GmMYB78 triggers soybean sensitivity to P. sojae by inhibiting the JA signaling pathway and the expression of pathogenesis-related genes or through the effects of the GmbHLH122-GmMYB78-GmbZIP25 cascade pathway. [ABSTRACT FROM AUTHOR]

Phytophthora root and stem rot of soybean (Glycine max), caused by the oomycete Phytophthora sojae, is an extremely destructive disease worldwide. In this study, we identified GmEIL1, which encodes an ethylene‐insensitive3 (EIN3) transcription factor. GmEIL1 was significantly induced following P. sojae infection of soybean plants. Compared to wild‐type soybean plants, transgenic soybean plants overexpressing GmEIL1 showed enhanced resistance to P. sojae and GmEIL1‐silenced RNA‐interference lines showed more severe symptoms when infected with P. sojae. We screened for target genes of GmEIL1 and confirmed that GmEIL1 bound directly to the GmERF113 promoter and regulated GmERF113 expression. Moreover, GmEIL1 positively regulated the expression of the pathogenesis‐related gene GmPR1. The GmEIL1‐regulated defence response to P. sojae involved both ethylene biosynthesis and the ethylene signalling pathway. These findings suggest that the GmEIL1‐GmERF113 module plays an important role in P. sojae resistance via the ethylene signalling pathway. [ABSTRACT FROM AUTHOR]

The strong aggregation of Poly(3-hexylthiophene) (P3HT) severely limits its use as the hole-transport material in emerging quantum dot photodetectors and photovoltaics. Herein, we propose a facile and cost-effective strategy to control the solution-state aggregation of hole transporting layers by designing a dual polythiophene blend based on P3HT and its alkylthio-substituted analogue named Poly(3-hexylthiothiophene) (P3HTT). In our photodetector device, we have used the dual polythiophene as the hole transport layer and achieved a specific detectivity (D*) on the order of 1012 Jones. In particular, by incorporating a small amount of P3HTT into the dual polythiophene mixture, we observed a remarkable 28% performance enhancement. This study provides a comprehensive analysis of the solution structure of the dual polythiophene blend, elucidates the evolution of the condensed matter structure, and ultimately presents a promising avenue for enhancing the performance of low-cost quantum dot photodetectors. [ABSTRACT FROM AUTHOR]

The emerging solution‐based solar cells and photodetectors have gained worldwide research interest over the past decades. Hole transport materials (HTMs) have greatly advanced the progress of these solution‐based electronics. Nevertheless, developing low‐cost and efficient HTMs is far from satisfactory. In this contribution, poly(3‐pentylthiophene) (P3PT) is introduced as a facile, low‐cost, and versatile dopant‐free polymer HTM for both quantum dot (QD) and perovskite electronic devices. Compared to the broadly used poly(3‐hexylthiophene), P3PT presents the reduced molecular aggregation and preferential face‐on orientation, which can markedly enhance the hole‐carrier transport in optoelectronic devices. Accordingly, P3PT can deliver the substantial improvement of photovoltaic performance from ∼8.6% to ∼9.5% for QD/polythiophene solar cells and from ∼16% to ∼18.8% for perovskite/polythiophene solar cells, which are both among the topmost values in the corresponding fields. Furthermore, P3PT HTMs can also significantly enhance the photodetection performance of QD and perovskite photodetectors by a factor of ∼3, indicating its great application potential in a variety of emerging optoelectronics. [ABSTRACT FROM AUTHOR]

Phytophthora root and stem rot caused by Phytophthora sojae Kaufmann and Gerdemann is a soil-borne disease severely affecting soybean production worldwide. Losses caused by P. sojae can be controlled by both major genes and quantitative trait locus. Here, we tested 112 short-season soybean cultivars from Northeast China for resistance to P. sojae. A total of 58 germplasms were resistant to 7–11 P. sojae strains. Among these, Mengdou 28 and Kejiao 10-262 may harbor either Rps3a or multiple Rps genes conferring resistance to P. sojae. The remaining 110 germplasms produced 91 reaction types and may contain new resistance genes or gene combinations. Partial resistance evaluation using the inoculum layer method revealed that 34 soybean germplasms had high partial resistance, with a mean disease index lower than 30. Combining the results of resistance and partial resistance analyses, we identified 35 excellent germplasm resources as potential elite materials for resistance and tolerance in future breeding programs. In addition, we compared the radicle inoculation method with the inoculum layer method to screen for partial resistance to P. sojae. Our results demonstrate that the radicle inoculation method could potentially replace the inoculum layer method to identify partial resistance against P. sojae, and further verification with larger samples is required in the future. [ABSTRACT FROM AUTHOR]

The emerging solution-processing photovoltaic technologies, e.g., quantum dot (QD) and organic solar cells, have witnessed unprecedented progress in the past decade. Nevertheless, both technologies have their own merits, holding promising potential to be leveraged for mutual win. Herein, a comprehensive and critical review of the state-of-the-art hybrid solar cells with three promising QDs (lead chalcogenide QDs, AgBiS2 QDs, and perovskite QDs) is delivered with the goal of further enhancing their performance and stability for large-scale applications. Firstly, we discussed the working principles of hybrid solar cells and highlighted the combined support of various structures. Subsequently, QD passivation with organic ligands was further outlined, focusing on further enhancing the performance of QD solar cells. Then, there is an in-depth discussion on worldwide research efforts to enhance the performance and stability of hybrid devices, including bulk-heterojunction, bilayer, and tandem structures. Finally, the remaining open challenges and our insights are presented to offer promising research directions for further performance breakthrough. [ABSTRACT FROM AUTHOR]

Phytophthora root rot is a destructive soybean disease worldwide, which is caused by the oomycete pathogen Phytophthora sojae (P. sojae). Wall-associated protein kinase (WAK) genes, a family of the receptor-like protein kinase (RLK) genes, play important roles in the plant signaling pathways that regulate stress responses and pathogen resistance. In our study, we found a putative Glycine max wall-associated protein kinase, GmWAK1, which we identified by soybean GmLHP1 RNA-sequencing. The expression of GmWAK1 was significantly increased by P. sojae and salicylic acid (SA). Overexpression of GmWAK1 in soybean significantly improved resistance to P. sojae, and the levels of phenylalanine ammonia-lyase (PAL), SA, and SA-biosynthesis-related genes were markedly higher than in the wild-type (WT) soybean. The activities of enzymatic superoxide dismutase (SOD) and peroxidase (POD) antioxidants in GmWAK1-overexpressing (OE) plants were significantly higher than those in in WT plants treated with P. sojae; reactive oxygen species (ROS) and hydrogen peroxide (H2O2) accumulation was considerably lower in GmWAK1-OE after P. sojae infection. GmWAK1 interacted with annexin-like protein RJ, GmANNRJ4, which improved resistance to P. sojae and increased intracellular free-calcium accumulation. In GmANNRJ4-OE transgenic soybean, the calmodulin-dependent kinase gene GmMPK6 and several pathogenesis-related (PR) genes were constitutively activated. Collectively, these results indicated that GmWAK1 interacts with GmANNRJ4, and GmWAK1 plays a positive role in soybean resistance to P. sojae via a process that might be dependent on SA and involved in alleviating damage caused by oxidative stress. [ABSTRACT FROM AUTHOR]

Ethylene response factors (ERFs) are involved in biotic and abiotic stress; however, the drought resistance mechanisms of many ERFs in soybeans have not been resolved. Previously, we proved that GmERF113 enhances resistance to the pathogen Phytophthora sojae in soybean. Here, we determined that GmERF113 is induced by 20% PEG-6000. Compared to the wild-type plants, soybean plants overexpressing GmERF113 (GmERF113-OE) displayed increased drought tolerance which was characterized by milder leaf wilting, less water loss from detached leaves, smaller stomatal aperture, lower Malondialdehyde (MDA) content, increased proline accumulation, and higher Superoxide dismutase (SOD) and Peroxidase (POD) activities under drought stress, whereas plants with GmERF113 silenced through RNA interference were the opposite. Chromatin immunoprecipitation and dual effector-reporter assays showed that GmERF113 binds to the GCC-box in the GmPR10-1 promoter, activating GmPR10-1 expression directly. Overexpressing GmPR10-1 improved drought resistance in the composite soybean plants with transgenic hairy roots. RNA-seq analysis revealed that GmERF113 downregulates abscisic acid 8′-hydroxylase 3 (GmABA8'-OH 3) and upregulates various drought-related genes. Overexpressing GmERF113 and GmPR10-1 increased the abscisic acid (ABA) content and reduced the expression of GmABA8'-OH3 in transgenic soybean plants and hairy roots, respectively. These results reveal that the GmERF113-GmPR10-1 pathway improves drought resistance and affects the ABA content in soybean, providing a theoretical basis for the molecular breeding of drought-tolerant soybean. [ABSTRACT FROM AUTHOR]

SUMMARY: Phytophthora root and stem rot is a worldwide soybean (Glycine max) disease caused by the soil‐borne pathogen Phytophthora sojae. This disease is devastating to soybean production, so improvement of resistance to P. sojae is a major target in soybean breeding. Mitogen‐activated protein kinase (MAPK) cascades are important signaling modules that convert environmental stimuli into cellular responses. Compared with extensive studies in Arabidopsis, the molecular mechanism of MAPK cascades in soybean disease resistance is barely elucidated. In this work, we found that the gene expression of mitogen‐activated protein kinase 6 (GmMPK6) was potently induced by P. sojae infection in the disease‐resistant soybean cultivar 'Suinong 10'. Overexpression of GmMPK6 in soybean resulted in enhanced resistance to P. sojae and silencing of GmMPK6 led to the opposite phenotype. In our attempt to dissect the role of GmMPK6 in soybean resistance to phytophthora disease, we found that MAPK kinase 4 (GmMKK4) and the ERF transcription factor GmERF113 physically interact with GmMPK6, and we determined that GmMKK4 could phosphorylate and activate GmMPK6, which could subsequently phosphorylate GmERF113 upon P. sojae infection, suggesting that P. sojae can stimulate the GmMKK4–GmMPK6–GmERF113 signaling pathway in soybean. Moreover, phosphorylation of GmERF113 by the GmMKK4–GmMPK6 module promoted GmERF113 stability, nuclear localization and transcriptional activity, which significantly enhanced expression of the defense‐related genes GmPR1 and GmPR10‐1 and hence improved disease resistance of the transgenic soybean seedlings. In all, our data reveal that the GmMKK4–GmMPK6–GmERF113 cascade triggers resistance to P. sojae in soybean and shed light on functions of MAPK kinases in plant disease resistance. Significance Statement: The GmMKK4–GmMPK6–GmERF113 cascade enhances resistance to soybean (Glycine max) phytophthora disease by successive phosphorylation events triggered by Phytophthora sojae. Our work provides new perspectives to develop strategies to improve plant disease resistance and insights into the roles of MAPK cascades in resistance against root and stem rot diseases. [ABSTRACT FROM AUTHOR]

Phytophthora root and stem rot in soybean (Glycine max) is a destructive disease worldwide, and hence improving crop resistance to the causal pathogen, P. sojae , is a major target for breeders. However, it remains largely unclear how the pathogen regulates the various affected signaling pathways in the host, which consist of complex networks including key transcription factors and their targets. We have previously demonstrated that GmBTB/POZ enhances soybean resistance to P. sojae and the associated defense response. Here, we demonstrate that GmBTB/POZ interacts with the transcription factor GmAP2 and promotes its ubiquitination. GmAP2 -RNAi transgenic soybean hairy roots exhibited enhanced resistance to P. sojae , whereas roots overexpressing GmAP2 showed hypersensitivity. GmWRKY33 was identified as a target of GmAP2, which represses its expression by directly binding to the promoter. GmWRKY33 acts as a positive regulator in the response of soybean to P. sojae. Overexpression of GmBTB/POZ released the GmAP2-regulated suppression of GmWRKY33 in hairy roots overexpressing GmAP2 and increased their resistance to P. sojae. Taken together, our results indicate that GmBTB/POZ-GmAP2 modulation of the P. sojae resistance response forms a novel regulatory mechanism, which putatively regulates the downstream target gene GmWRKY33 in soybean. [ABSTRACT FROM AUTHOR]

Improving soil productivity is the best way to increase grain production by 1% annually for feeding the rising population within the next 20 years in China. Nevertheless, how soybean yield and seed quality are affected by improving soil quality via consecutive manure addition are still unclear. A 7‐year consecutive cattle manure addition experiment was conducted under a soybean [Glycine max (Merrill.) L.] and maize (Zea mays L.) rotation in Mollisols. Treatments were as follows: CK: the non‐fertilizer control; CF: chemical fertilizer (NPK); CFM1: CF + 15 Mg ha−1 cattle manure; CFM2: CF + 30 Mg ha−1 cattle manure. The results showed CFM1 significantly increased soybean yield by 22%–105% and 21%–86% compared to CK and CF during 2014–2018. The consecutive cattle manure addition significantly increased the proportion of macro‐aggregates (1–0.25 mm) but decreased the proportion of micro‐aggregates (0.25–0.053 mm) and slit (<0.053 mm). The SOC storage in the large (>1 mm) and small macro‐aggregates (1–0.25 mm) was higher (by 24%–156%) under cattle manure addition than that under CK and CF. The soil productivity was enhanced by cattle manure addition because of the increase in soil available nutrients, that is, NH4+‐N and NO3−‐N, and Olsen‐P, all of which had positive correlations with the yield increase. At least 36% of soybean yield variation under CFM1 could be attributed to the indirect effect of pH value on increasing soil available nutrients concentrations. The cattle manure addition increased soybean seed oil concentration but decreased protein concentration. However, there were no differences in yield and quality between CFM1 and CFM2 after 7‐year of the treatment. It suggests that cattle manure addition at 15 Mg ha−1 is a practical approach to improve Mollisols' productivity and SOC stability. [ABSTRACT FROM AUTHOR]

Phytophthora root rot, caused by Phytophthora sojae is a destructive disease of soybean (Glycine max) worldwide. We previously confirmed that the bHLH transcription factor GmPIB1 (P. sojae -inducible bHLH transcription factor) reduces accumulation of reactive oxygen species (ROS) in cells by inhibiting expression of the peroxidase-related gene GmSPOD thus improving the resistance of hairy roots to P. sojae. To identify proteins interacting with GmPIB1 and assess their participation in the defense response to P. sojae , we obtained transgenic soybean hairy roots overexpressing GmPIB1 by Agrobacterium rhizogenes mediated transformation and examined GmPIB1 protein–protein interactions using immunoprecipitation combined with mass spectrometry. We identified 392 proteins likely interacting with GmPIB1 and selected 20 candidate genes, and only 26S proteasome regulatory subunit GmPSMD (Genbank accession no. XP_014631720) interacted with GmPIB1 in luciferase complementation and pull-down experiments and yeast two-hybrid assays. Overexpression of GmPSMD (GmPSMD- OE) in soybean hairy roots remarkably improved resistance to P. sojae and RNA interference of GmPSMD (GmPSMD -RNAi) increased susceptibility. In addition, accumulation of total ROS and hydrogen peroxide (H2O2) in GmPSMD- OE transgenic soybean hairy roots were remarkably lower than those of the control after P. sojae infection. Moreover, in GmPSMD -RNAi transgenic soybean hairy roots, H2O2 and the accumulation of total ROS exceeded those of the control. There was no obvious difference in superoxide anion (O2–) content between control and transgenic hairy roots. Antioxidant enzymes include peroxidase (POD), glutathione peroxidase (GPX), superoxide dismutase (SOD), catalase (CAT) are responsible for ROS scavenging in soybean. The activities of these antioxidant enzymes were remarkably higher in GmPSMD -OE transgenic soybean hairy roots than those in control, but were reduced in GmPSMD -RNAi transgenic soybean hairy roots. Moreover, the activity of 26S proteasome in GmPSMD -OE and GmPIB1 -OE transgenic soybean hairy roots was significantly higher than that in control and was significantly lower in PSMD -RNAi soybean hairy roots after P. sojae infection. These data suggest that GmPSMD might reduce the production of ROS by improving the activity of antioxidant enzymes such as POD, SOD, GPX, CAT, and GmPSMD plays a significant role in the response of soybean to P. sojae. Our study reveals a valuable mechanism for regulation of the pathogen response by the 26S proteasome in soybean. [ABSTRACT FROM AUTHOR]

Phytophthora root and stem rot, a destructive disease of soybean [ Glycine max (L.) Merr.], is caused by the oomycete Phytophthora sojae. However, how the disease resistance mechanisms of soybean respond to P. sojae infection remains unclear. Previously, we showed that GmWRKY31, which interacts with a sucrose non-fermenting-1(SNF1)-related protein kinase (SnRK), enhances resistance to P. sojae in soybean. Here, we report that the membrane-localized SnRK GmSnRK1.1 is involved in the soybean host response to P. sojae. The overexpression of GmSnRK1.1 (GmSnRK1.1 -OE) increased soybean resistance to P. sojae , and the RNA interference (RNAi)-mediated silencing of GmSnRK1.1 (GmSnRK1.1 -R) reduced resistance to P. sojae. Moreover, the activities and transcript levels of the antioxidant enzymes superoxide dismutase and peroxidase were markedly higher in the GmSnRK1.1 -OE transgenic soybean plants than in the wild type (WT), but were reduced in the GmSnRK1.1 -R plants. Several isoflavonoid phytoalexins related genes GmPAL , GmIFR , Gm4CL and GmCHS were significantly higher in "Suinong 10" and GmSnRK1.1 -OE lines than these in "Dongnong 50," and were significantly lower in GmSnRK1.1 -R lines. In addition, the accumulation of salicylic acid (SA) and the expression level of the SA biosynthesis-related gene were significantly higher in the GmSnRK1.1 -OE plants than in the WT and GmSnRK1.1 -R plants, moreover, SA biosynthesis inhibitor treated GmSnRK1.1 -R lines plants displayed clearly increased pathogen biomass compared with H2O-treated plants after 24 h post-inoculation. These results showed that GmSnRK1.1 positively regulates soybean resistance to P. sojae , potentially functioning via effects on the expression of SA-related genes and increased accumulation of SA. [ABSTRACT FROM AUTHOR]

Phytophthora root and stem rot of soybean (Glycine max (L.) Merr.) caused by Phytophthora sojae is a destructive disease worldwide. The enzyme 4-coumarate: CoA ligase (4CL) has been extensively studied with regard to plant responses to pathogens. However, the molecular mechanism of the response of soybean 4CL to P. sojae remains unclear. In a previous study, a highly upregulated 4CL homologue was characterised through suppressive subtractive hybridisation library and cDNA microarrays, in the resistant soybean cultivar 'Suinong 10' after infection with P. sojae race 1. Here, we isolated the full-length EST, and designated as GmPI4L (P. sojae -inducible 4CL gene) in this study, which is a novel member of the soybean 4CL gene family. GmPI4L has 34–43% over all amino acid sequence identity with other plant 4CLs. Overexpression of GmPI4L enhances resistance to P. sojae in transgenic soybean plants. The GmPI4L is located in the cell membrane when transiently expressed in Arabidopsis protoplasts. Further analyses showed that the contents of daidzein, genistein, and the relative content of glyceollins are significantly increased in overexpression GmPI4L soybeans. Taken together, these results suggested that GmPI4L plays an important role in response to P. sojae infection, possibly by enhancing the content of glyceollins, daidzein, and genistein in soybean. Glyceollins and isoflavones are soybean-derived phytoalexins in response to Phytophthora sojae that causes stem and root rot on soybeans worldwide. To understand the function of Gm4CL, we analysed and found that GmPI4L improves defence against P. sojae by enhancing glyceollins and isoflavones content. This study provides the theoretical foundation for clarifying the mechanism of the phenylpropanoid pathway in disease resistance in soybean. [ABSTRACT FROM AUTHOR]

Summary: Phytophthora sojae is a destructive pathogen of soybean [Glycine max (L.) Merr.] which causes stem and root rot on soybean plants worldwide. However, the pathogenesis and molecular mechanism of plant defence responses against P. sojae are largely unclear. Herein, we document the underlying mechanisms and function of a novel BTB/POZ protein, GmBTB/POZ, which contains a BTB/POZ domain found in certain animal transcriptional regulators, in host soybean plants in response to P. sojae. It is located in the cell nucleus and is transcriptionally up‐regulated by P. sojae. Overexpression of GmBTB/POZ in soybean resulted in enhanced resistance to P. sojae. The activities and expression levels of enzymatic superoxide dismutase (SOD) and peroxidase (POD) antioxidants were significantly higher in GmBTB/POZ‐overexpressing (GmBTB/POZ‐OE) transgenic soybean plants than in wild‐type (WT) plants treated with sterile water or infected with P. sojae. The transcript levels of defence‐associated genes were also higher in overexpressing plants than in WT on infection. Moreover, salicylic acid (SA) levels and the transcript levels of SA biosynthesis‐related genes were markedly higher in GmBTB/POZ‐OE transgenic soybean than in WT, but there were almost no differences in jasmonic acid (JA) levels or JA biosynthesis‐related gene expression between GmBTB/POZ‐OE and WT soybean lines. Furthermore, exogenous SA application induced the expression of GmBTB/POZ and inhibited the increase in P. sojae biomass in both WT and GmBTB/POZ‐OE transgenic soybean plants. Taken together, these results suggest that GmBTB/POZ plays a positive role in P. sojae resistance and the defence response in soybean via a process that might be dependent on SA. [ABSTRACT FROM AUTHOR]

Although the effect of elevated CO2 (eCO2) on soybean yield has been well documented, few studies have addressed seed quality, particularly at the fresh edible (R6) and mature stages (R8). Under the current global scenario of increasing CO2 levels, this potentially threatens the nutritional content and quality of food crops. Using four soybean cultivars, we assessed the effects of eCO2 on the concentrations of crude protein, crude oil, and isoflavones and analyzed the changes in free amino acids, fatty acids, and mineral elements in seeds. At R6, eCO2 had no influence on soybean seed protein and oil concentrations. At R8, eCO2 significantly decreased seed protein concentration but increased seed oil concentration; it also significantly decreased total free amino acid concentration. However, at the same stage, the proportion of oleic acid (18:1) among fatty acids increased in response to eCO2 in the cultivars of Zhongke-maodou 2 (ZK-2) and Zhongke-maodou 3 (ZK-3), and a similar trend was found for linoleic acid (18:2) in Zhongke-maodou 1 (ZK-1) and Hei-maodou (HD). Total isoflavone concentrations increased significantly at both the R6 and R8 stages in response to eCO2. Compared with ambient CO2, the concentrations of K, Ca, Mg, P, and S increased significantly under eCO2 at R6, while the Fe concentration decreased significantly. The response of Zn and Mn concentrations to eCO2 varied among cultivars. At R8 and under eCO2, Mg, S, and Ca concentrations increased significantly, while Zn and Fe concentrations decreased significantly. These findings suggest that eCO2 is likely to benefit from the accumulation of seed fat and isoflavone but not from that of protein. In this study, the response of seed mineral nutrients to eCO2 varied between cultivars. [ABSTRACT FROM AUTHOR]

Phytophthora root and stem rot of soybean, caused by Phytophthora sojae (P. sojae), is a destructive disease in many soybean planting regions worldwide. In a previous study, an expressed sequence tag (EST) homolog of the major allergen Pru ar 1 in apricot (Prunus armeniaca) was identified up-regulated in the highly resistant soybean ‘Suinong 10’ infected with P. sojae. Here, the full length of the EST was isolated using rapid amplification of cDNA ends (RACE). It showed the highest homolgy of 53.46% with Gly m 4 after comparison with the eight soybean allergen families reported and was named Gly m 4-like (Gly m 4l, GenBank accession no. HQ913577.1). The cDNA full length of Gly m 4l was 707 bp containing a 474 bp open reading frame encoding a polypeptide of 157 amino acids. Sequence analysis suggests that Gly m 4l contains a conserved ‘P-loop’ (phosphate-binding loop) motif at residues 47–55 aa and a Bet v 1 domain at residues 87–120 aa. The transcript abundance of Gly m 4l was significantly induced by P. sojae, salicylic acid (SA), NaCl, and also responded to methyl jasmonic acid (MeJA) and ethylene (ET). The recombinant Gly m 4l protein showed RNase activity and displayed directly antimicrobial activity that inhibited hyphal growth and reduced zoospore release in P. sojae. Further analyses showed that the RNase activity of the recombinant protein to degrading tRNA was significantly affected in the presence of zeatin. Over-expression of Gly m 4l in susceptible ‘Dongnong 50’ soybean showed enhanced resistance to P. sojae. These results indicated that Gly m 4l protein played an important role in the defense of soybean against P. sojae infection. [ABSTRACT FROM AUTHOR]

Pathogenesis-related proteins (PR proteins) play crucial roles in the plant defense system. A novel PRP gene was isolated from highly resistant soybean infected with Phytophthora sojae (P. sojae) and was named GmPRP (GenBank accession number: KM506762). The amino acid sequences of GmPRP showed identities of 74%, 73%, 72% and 69% with PRP proteins from Vitis vinifera, Populus trichocarpa, Citrus sinensis and Theobroma cacao, respectively. Quantitative real-time reverse transcription PCR (qRT-PCR) data showed that the expression of GmPRP was highest in roots, followed by the stems and leaves. GmPRP expression was upregulated in soybean leaves infected with P. sojae. Similarly, GmPRP expression also responded to defense/stress signaling molecules, including salicylic acid (SA), ethylene (ET), abscisic acid (ABA) and jasmonic acid (JA). GmPRP was localized in the cell plasma membrane and cytoplasm. Recombinant GmPRP protein exhibited ribonuclease activity and significant inhibition of hyphal growth of P. sojae 1 in vitro. Overexpression of the GmPRP gene in T2 transgenic tobacco and T2 soybean plants resulted in enhanced resistance to Phytophthora nicotianae (P. nicotianae) and P. sojae race 1, respectively. These results indicated that the GmPRP protein played an important role in the defense of soybean against P. sojae infection. [ABSTRACT FROM AUTHOR]

Aims: In agricultural systems, residue amendment is an important practice for nutrient management, but the role of microbes in mineralization of crop residue nitrogen (N) is not well known. Therefore, this study aimed to examine how the residue N mineralization was associated with changes of the microbial community composition in crop rhizosphere.A rhizobox system was deployed to separate the rhizosphere zone into the root-growth (central), and 2 mm (proximal) and 4 mm (transitional) zones away from the central zone, and the gradient change of the residue-N mineralization along the zones was assessed. Soybean plants were grown in a Mollisol without or with amendment of 15N-labelled soybean and maize residues. Furthermore, amplicon sequencing was performed to detect the shift of microbial community composition associated with the residue-N mineralization.The residue-N was mineralized faster in the rhizosphere than the bulk soil, and from soybean residue than maize residue. Greater enrichment of taxa against the unit of residue-N mineralization in the soybean than maize residue treatment was correspondent with the enriched ammonification genes, likely contributing to the enhanced mineralization of soybean residue-N in the rhizosphere. A gradual increase in dissolved organic C and a decrease in available N concentration from the central root zone to the bulk soil, might shift bacterial community favoring the residue-N mineralization in the rhizosphere.The spatial changes in chemical properties across the rhizosphere lead to the recruitment of microbiome taxa to enhance the mineralization of N derived from crop residues.Methods: In agricultural systems, residue amendment is an important practice for nutrient management, but the role of microbes in mineralization of crop residue nitrogen (N) is not well known. Therefore, this study aimed to examine how the residue N mineralization was associated with changes of the microbial community composition in crop rhizosphere.A rhizobox system was deployed to separate the rhizosphere zone into the root-growth (central), and 2 mm (proximal) and 4 mm (transitional) zones away from the central zone, and the gradient change of the residue-N mineralization along the zones was assessed. Soybean plants were grown in a Mollisol without or with amendment of 15N-labelled soybean and maize residues. Furthermore, amplicon sequencing was performed to detect the shift of microbial community composition associated with the residue-N mineralization.The residue-N was mineralized faster in the rhizosphere than the bulk soil, and from soybean residue than maize residue. Greater enrichment of taxa against the unit of residue-N mineralization in the soybean than maize residue treatment was correspondent with the enriched ammonification genes, likely contributing to the enhanced mineralization of soybean residue-N in the rhizosphere. A gradual increase in dissolved organic C and a decrease in available N concentration from the central root zone to the bulk soil, might shift bacterial community favoring the residue-N mineralization in the rhizosphere.The spatial changes in chemical properties across the rhizosphere lead to the recruitment of microbiome taxa to enhance the mineralization of N derived from crop residues.Results: In agricultural systems, residue amendment is an important practice for nutrient management, but the role of microbes in mineralization of crop residue nitrogen (N) is not well known. Therefore, this study aimed to examine how the residue N mineralization was associated with changes of the microbial community composition in crop rhizosphere.A rhizobox system was deployed to separate the rhizosphere zone into the root-growth (central), and 2 mm (proximal) and 4 mm (transitional) zones away from the central zone, and the gradient change of the residue-N mineralization along the zones was assessed. Soybean plants were grown in a Mollisol without or with amendment of 15N-labelled soybean and maize residues. Furthermore, amplicon sequencing was performed to detect the shift of microbial community composition associated with the residue-N mineralization.The residue-N was mineralized faster in the rhizosphere than the bulk soil, and from soybean residue than maize residue. Greater enrichment of taxa against the unit of residue-N mineralization in the soybean than maize residue treatment was correspondent with the enriched ammonification genes, likely contributing to the enhanced mineralization of soybean residue-N in the rhizosphere. A gradual increase in dissolved organic C and a decrease in available N concentration from the central root zone to the bulk soil, might shift bacterial community favoring the residue-N mineralization in the rhizosphere.The spatial changes in chemical properties across the rhizosphere lead to the recruitment of microbiome taxa to enhance the mineralization of N derived from crop residues.Conclusions: In agricultural systems, residue amendment is an important practice for nutrient management, but the role of microbes in mineralization of crop residue nitrogen (N) is not well known. Therefore, this study aimed to examine how the residue N mineralization was associated with changes of the microbial community composition in crop rhizosphere.A rhizobox system was deployed to separate the rhizosphere zone into the root-growth (central), and 2 mm (proximal) and 4 mm (transitional) zones away from the central zone, and the gradient change of the residue-N mineralization along the zones was assessed. Soybean plants were grown in a Mollisol without or with amendment of 15N-labelled soybean and maize residues. Furthermore, amplicon sequencing was performed to detect the shift of microbial community composition associated with the residue-N mineralization.The residue-N was mineralized faster in the rhizosphere than the bulk soil, and from soybean residue than maize residue. Greater enrichment of taxa against the unit of residue-N mineralization in the soybean than maize residue treatment was correspondent with the enriched ammonification genes, likely contributing to the enhanced mineralization of soybean residue-N in the rhizosphere. A gradual increase in dissolved organic C and a decrease in available N concentration from the central root zone to the bulk soil, might shift bacterial community favoring the residue-N mineralization in the rhizosphere.The spatial changes in chemical properties across the rhizosphere lead to the recruitment of microbiome taxa to enhance the mineralization of N derived from crop residues. [ABSTRACT FROM AUTHOR]

[Display omitted] • Maize residue amendment altered the N accumulation pattern in soybean. • Residue N was the minimal source of grain N in soybean. • Residue amendment increased the nodule density and N 2 fixation efficiency. • The diazotrophic community abundance was enriched with residue amendment. Crop residue amendment to soil is recommended as an effective management practice to return nutrients, especially in the maize-soybean rotation system where large amounts of maize residues are produced. Quantifying the utilisation of maize-residue N by the subsequent soybean crop is essential for optimising the N fertilisation strategy for sustainable production. However, whether and how maize residue amendment alters N acquisition in soybean plants are largely unknown. It was hypothesised that maize residue would supply N and enhance N 2 fixation to meet the N requirements of subsequent soybeans. Three treatments, namely: 1) chemical fertiliser (55.2, 35.2 and 22.4 kg ha−1 of N, P and K, respectively), 2) maize residue (8 t ha−1), and 3) non-fertiliser were applied in a maize-soybean rotation system in a Mollisol soil. It was demonstrated that soybean seed yield in the maize-residue treatment was the same as that in the chemical fertiliser treatment, with 2.9 vs. 3.2 t ha−1 in 2014, 2.7 vs. 2.6 t ha−1 in 2016, and 3.0 vs. 3.1 t ha−1 in 2018. A follow-up pot experiment using 15N-labelled residue indicated that the residue-derived N accounted for 0.5 % of the total N in soybean seeds and the proportion of symbiotically fixed N reached 82 %. The amount of fixed N during the pod-filling period in the residue treatment was 0.66 g plant-1, which was 49 % and 41 % higher than those in the chemical fertiliser and non-fertiliser treatments, respectively. The stimulation of N 2 fixation was associated with an increase in fixed N per nodule and the enrichment of diazotrophs in the rhizosphere of soybean. With maize residue amendment, the increased N 2 -fixing capability of nodules during the reproductive period, rather than residue-derived N, fulfilled the N demand for maintaining seed yield of soybean. In the maize-soybean rotation system, maize residue amendment would facilitate the N 2 fixation to partly substitute for N fertiliser for soybean production in Mollisols. [ABSTRACT FROM AUTHOR]

Phytophthora root and stem rot in soybean (Glycine max) is a destructive disease worldwide, and hence improving crop resistance to the causal pathogen, P. sojae, is a major target for breeders. However, it remains largely unclear how the pathogen regulates the various affected signaling pathways in the host, which consist of complex networks including key transcription factors and their targets. We have previously demonstrated that GmBTB/POZ enhances soybean resistance to P. sojae and the associated defense response. Here, we demonstrate that GmBTB/POZ interacts with the transcription factor GmAP2 and promotes its ubiquitination. GmAP2-RNAi transgenic soybean hairy roots exhibited enhanced resistance to P. sojae, whereas roots overexpressing GmAP2 showed hypersensitivity. GmWRKY33 was identified as a target of GmAP2, which represses its expression by directly binding to the promoter. GmWRKY33 acts as a positive regulator in the response of soybean to P. sojae. Overexpression of GmBTB/POZ released the GmAP2-regulated suppression of GmWRKY33 in hairy roots overexpressing GmAP2 and increased their resistance to P. sojae. Taken together, our results indicate that GmBTB/POZ-GmAP2 modulation of the P. sojae resistance response forms a novel regulatory mechanism, which putatively regulates the downstream target gene GmWRKY33 in soybean., (© The Author(s) 2021. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Owing to the advantages of low synthetic cost and high scalability of synthesis, polythiophene and its derivatives (PTs) have been of interest in the community of organic photovoltaics (OPVs). Nevertheless, the typical efficiency of PT based photovoltaic devices reported so far is much lower than those of the prevailing push-pull type conjugated polymer donors. Recent studies have underscored that the excessively low miscibility between PT and nonfullerene acceptor is the major reason accounting for the unfavorable active layer morphology and the inferior performance of OPVs based on a well-known PT, namely PDCBT-Cl and a non-halogenated nonfullerene acceptor IDIC. How to manipulate the miscibility between PT and acceptor molecule is important for further improving the device efficiency of this class of potentially low-cost blend systems. In this study, we introduced different numbers of F atoms to the end groups of IDIC to tune the intermolecular interaction of the hypo-miscible blend system (PDCBT-Cl:IDIC). Based on calorimetric, microscopic, and scattering characterizations, a clear relationship between the number of F atoms, miscibility, and device performance was established. With the increased number of F atoms in IDIC, the resulting acceptors exhibited enhanced miscibility with PDCBT-Cl, and the domain sizes of the blend films were reduced substantially. As a result, distinctively different photovoltaic performances were achieved for these blend systems. This study demonstrates that varying the number of F atoms in the acceptors is a feasible way to manipulate the molecular interaction and the film morphology toward high-performance polythiophene:nonfullerene based OPVs., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Liang, Gao, Zhang, Wu, Peng, Li, Ye and Geng.)

Sucrose is the main photosynthesis product of plants and the fundamental carbon skeleton monomer and energy supply for seed formation and development. Drought stress induces decreased photosynthetic carbon assimilation capacity, and seriously affects seed weight in soybean. However, little is known about the relationship between decreases in soybean seed yield and disruption of sucrose metabolism and transport balance in leaves and seeds during the reproductive stages of crop growth. Three soybean cultivars with similar growth periods, "Shennong17", "Shennong8", and "Shennong12", were subjected to drought stress during reproductive growth for 45 days. Drought stress significantly reduced leaf photosynthetic rate, shoot biomass, and seed weight by 63.93, 33.53, and 41.65%, respectively. Drought stress increased soluble sugar contents, the activities of sucrose phosphate synthase, sucrose synthase, and acid invertase enzymes, and up-regulated the expression levels of GmSPS1 , GmSuSy2 , and GmA-INV , but decreased starch content by 15.13% in leaves. Drought stress decreased the contents of starch, fructose, and glucose in seeds during the late seed filling stages, while it induced sucrose accumulation, which resulted in a decreased hexose-to-sucrose ratio. In developing seeds, the activities of sucrose synthesis and degradation enzymes, the expression levels of genes related to metabolism, and the expression levels of sucrose transporter genes were enhanced during early seed development under drought stress; however, under prolonged drought stress, all of them decreased. These results demonstrated that drought stress enhances the capacity for unloading sucrose into seeds and activated sucrose metabolism during early seed development. At the middle and late seed filling stages, sucrose flow from leaves to seeds was diminished, and the balance of sucrose metabolism was impaired in seeds, resulting in seed mass reduction. The different regulation strategies in sucrose allocation, metabolism, and transport during different seed development stages may be one of the physiological mechanisms for soybean plants to resist drought stress.

Although the effect of elevated CO 2 (eCO 2 ) on soybean yield has been well documented, few studies have addressed seed quality, particularly at the fresh edible (R6) and mature stages (R8). Under the current global scenario of increasing CO 2 levels, this potentially threatens the nutritional content and quality of food crops. Using four soybean cultivars, we assessed the effects of eCO 2 on the concentrations of crude protein, crude oil, and isoflavones and analyzed the changes in free amino acids, fatty acids, and mineral elements in seeds. At R6, eCO 2 had no influence on soybean seed protein and oil concentrations. At R8, eCO 2 significantly decreased seed protein concentration but increased seed oil concentration; it also significantly decreased total free amino acid concentration. However, at the same stage, the proportion of oleic acid (18:1) among fatty acids increased in response to eCO 2 in the cultivars of Zhongke-maodou 2 (ZK-2) and Zhongke-maodou 3 (ZK-3), and a similar trend was found for linoleic acid (18:2) in Zhongke-maodou 1 (ZK-1) and Hei-maodou (HD). Total isoflavone concentrations increased significantly at both the R6 and R8 stages in response to eCO 2 . Compared with ambient CO 2 , the concentrations of K, Ca, Mg, P, and S increased significantly under eCO 2 at R6, while the Fe concentration decreased significantly. The response of Zn and Mn concentrations to eCO 2 varied among cultivars. At R8 and under eCO 2 , Mg, S, and Ca concentrations increased significantly, while Zn and Fe concentrations decreased significantly. These findings suggest that eCO 2 is likely to benefit from the accumulation of seed fat and isoflavone but not from that of protein. In this study, the response of seed mineral nutrients to eCO 2 varied between cultivars.

Nitrogen deficiency limits crop performance under elevated CO 2 (eCO 2 ), depending on the ability of plant N uptake. However, the dynamics and redistribution of N 2 fixation, and fertilizer and soil N use in legumes under eCO 2 have been little studied. Such an investigation is essential to improve the adaptability of legumes to climate change. We took advantage of genotype-specific responses of soybean to increased CO 2 to test which N-uptake phenotypes are most strongly related to enhanced yield. Eight soybean cultivars were grown in open-top chambers with either 390 ppm (aCO 2 ) or 550 ppm CO 2 (eCO 2 ). The plants were supplied with 100 mg N kg -1 soil as 15 N-labeled calcium nitrate, and harvested at the initial seed-filling (R5) and full-mature (R8) stages. Increased yield in response to eCO 2 correlated highly ( r = 0.95) with an increase in symbiotically fixed N during the R5 to R8 stage. In contrast, eCO 2 only led to small increases in the uptake of fertilizer-derived and soil-derived N during R5 to R8, and these increases did not correlate with enhanced yield. Elevated CO 2 also decreased the proportion of seed N redistributed from shoot to seeds, and this decrease strongly correlated with increased yield. Moreover, the total N uptake was associated with increases in fixed-N per nodule in response to eCO 2 , but not with changes in nodule biomass, nodule density, or root length.

Phytophthora root and stem rot of soybean [Glycine max (L.) Merr.] caused by Phytophthora sojae is a destructive disease worldwide. Phenylalanine ammonia-lyase (PAL) is one of the most extensively studied enzymes related to plant responses to biotic and abiotic stresses. However, the molecular mechanism of PAL in soybean in response to P. sojae is largely unclear. Here, we characterize a novel member of the soybean PAL gene family, GmPAL2.1, which is significantly induced by P. sojae. Overexpression and RNA interference analysis demonstrates that GmPAL2.1 enhances resistance to P. sojae in transgenic soybean plants. In addition, the PAL activity in GmPAL2.1-OX transgenic soybean is significantly higher than that of non-transgenic plants after infection with P. sojae, while that in GmPAL2.1-RNAi soybean plants is lower. Further analyses show that the daidzein, genistein and salicylic acid (SA) levels and the relative content of glyceollins are markedly increased in GmPAL2.1-OX transgenic soybean. Taken together, these results suggest the important role of GmPAL2.1 functioning as a positive regulator in the soybean response to P. sojae infection, possibly by enhancing the content of glyceollins, daidzein, genistein and SA.

Phytophthora root and stem rot caused by the oomycete pathogen Phytophthora sojae is a destructive disease of soybean worldwide. Plant dirigent proteins (DIR) are proposed to have roles in biosynthesis of either lignan or lignin-like molecules, and are important for defense responses, secondary metabolism, and pathogen resistance. In the present work, a novel DIR gene expressed sequence tag is identified as up-regulated in the highly resistant soybean cultivar 'Suinong 10' inoculated with P. sojae . The full length cDNA is isolated using rapid amplification of cDNA ends, and designated GmDIR22 (GenBank accession no. HQ&#95;993047). The full length GmDIR22 is 789 bp and contains a 567 bp open reading frame encoding a polypeptide of 188 amino acids. The sequence analysis indicated that GmDIR22 contains a conserved dirigent domain at amino acid residues 43-187. The quantitative real-time reverse transcription PCR demonstrated that soybean GmDIR22 mRNA is expressed most highly in stems, followed by roots and leaves. The treatments with stresses demonstrated that GmDIR22 is significantly induced by P. sojae and gibberellic acid (GA 3 ), and also responds to salicylic acid, methyl jasmonic acid, and abscisic acid. The GmDIR22 is targeted to the cytomembrane when transiently expressed in Arabidopsis protoplasts. Moreover, The GmDIR22 recombinant protein purified from Escherichia coli could effectively direct E -coniferyl alcohol coupling into lignan (+)-pinoresinol. Accordingly, the overexpression of GmDIR22 in transgenic soybean increased total lignan accumulation. Moreover, the lignan extracts from GmDIR22 transgenic plants effectively inhibits P. sojae hyphal growth. Furthermore, the transgenic overexpression of GmDIR22 in the susceptible soybean cultivar 'Dongnong 50' enhances its resistance to P. sojae . Collectively, these data suggested that the primary role of GmDIR22 is probably involved in the regulation of lignan biosynthesis, and which contributes to resistance to P. sojae .

Phytophthora root and stem rot of soybean [ Glycine max (L.) Merr.] caused by the oomycete Phytophthora sojae , is a destructive disease worldwide. The molecular mechanism of the soybean response to P. sojae is largely unclear. We report a novel WRKY transcription factor (TF) in soybean, GmWRKY31, in the host response to P. sojae . Overexpression and RNA interference analysis demonstrated that GmWRKY31 enhanced resistance to P. sojae in transgenic soybean plants. GmWRKY31 was targeted to the nucleus, where it bound to the W-box and acted as an activator of gene transcription. Moreover, we determined that GmWRKY31 physically interacted with GmHDL56, which improved resistance to P. sojae in transgenic soybean roots. GmWRKY31 and GmHDL56 shared a common target GmNPR1 which was induced by P. sojae . Overexpression and RNA interference analysis demonstrated that GmNPR1 enhanced resistance to P. sojae in transgenic soybean plants. Several pathogenesis-related ( PR ) genes were constitutively activated, including GmPR1a , GmPR2 , GmPR3 , GmPR4 , GmPR5a , and GmPR10 , in soybean plants overexpressing GmNPR1 transcripts. By contrast, the induction of PR genes was compromised in transgenic GmNPR1 -RNAi lines. Taken together, these findings suggested that the interaction between GmWRKY31 and GmHDL56 enhances resistance to P. sojae by regulating defense-related gene expression in soybean.

Phytophthora root and stem rot, caused by Phytophthora sojae, is an economically important disease of soybean (Glycine max) in Heilongjiang Province, China. The objectives of this research were to determine the race profile of P. sojae in Heilongjiang and evaluate soybean cultivars for reactions to the pathogen races. A total of 96 single-zoospore P. sojae isolates were obtained from soil samples collected from 35 soybean fields in 18 counties in Heilongjiang from 2005 to 2007. Eight races of P. sojae, including races 1, 3, 4, 5, 9, 13, 44, and 54, were identified on a set of eight differentials, each containing a single resistance Rps gene, from 80 of the 96 isolates. Races 1 and 3 were predominant races, comprising 58 and 14 isolates, and representing 60 and 7% of the pathogen population, respectively. Races 4, 5, 44, and 54 were identified for the first time in Heilongjiang, and each was represented by two to three isolates only. Sixty-two soybean cultivars commonly grown in Heilongjiang Province were evaluated for their resistance to the eight P. sojae races identified using the hypocotyl inoculation technique. Based on the percentage of plant mortality rated 5 days after inoculation, 44 cultivars were resistant (<30% mortality) to at least one race. These cultivars may be used as sources of resistance in soybean breeding programs.

The internal transcribed spacer (ITS) region (ITS1, ITS2 and 5.8S rDNA) of the nuclear ribosomal DNA (nrDNA) was amplified via the PCR method in seventeen different isolates of Phytophthora sojae using the common primers of the ITS of fungi. Around 800 bp-1,000 bp fragments were obtained based on the DL2000 marker and the sequences of the PCR products were tested. Taking isolate USA as outgroup, the phylogenetic tree was constructed by means of maximum parsimony analysis, and the genetic evolution among isolates was analyzed. The results showed that there is a great difference between the base constitution of ITS1 and ITS2 among various isolates. The seventeen isolates are classified into three groups, and the isolates from the same region belong to the same group, which shows the variation in geography.