Apple replant disease(ARD)has led to severe yield and quality reduction in the apple industry.Fusarium solani(F.solani)has been identified as one of the main microbial pathogens responsible for ARD.Auxin(indole-3-acet...Apple replant disease(ARD)has led to severe yield and quality reduction in the apple industry.Fusarium solani(F.solani)has been identified as one of the main microbial pathogens responsible for ARD.Auxin(indole-3-acetic acid,IAA),an endogenous hormone in plants,is involved in almost all plant growth and development processes and plays a role in plant immunity against pathogens.Gretchen Hagen3(GH3)is one of the early/primary auxin response genes.The aim of this study was to evaluate the function of MdGH3-2 and MdGH3-12 in the defense response of F.solani by treating MdGH3-2/12 RNAi plants with F.solani.The results show that under F.solani infection,RNAi of MdGH3-2/12 inhibited plant biomass accumulation and exacerbated root damage.After inoculation with F.solani,MdGH3-2/12 RNAi inhibited the biosynthesis of acid-amido synthetase.This led to the inhibition of free IAA combining with amino acids,resulting in excessive free IAA accumulation.This excessive free IAA altered plant tissue structure,accelerated fungal hyphal invasion,reduced the activity of antioxidant enzymes(SOD,POD and CAT),increased the reactive oxygen species(ROS)level,and reduced total chlorophyll content and photosynthetic ability,while regulating the expression of PR-related genes including PR1,PR4,PR5 and PR8.It also changed the contents of plant hormones and amino acids,and ultimately reduced the resistance to F.solani.In conclusion,these results demonstrate that MdGH3-2 and MdGH3-12 play an important role in apple tolerance to F.solani and ARD.展开更多
Rice sheath blight, caused by Rhizoctonia solani AG1-IA, is a major disease in rice-growing areas worldwide. Effectors of phytopathogenic fungi play important roles during the infection process of fungal pathogens ont...Rice sheath blight, caused by Rhizoctonia solani AG1-IA, is a major disease in rice-growing areas worldwide. Effectors of phytopathogenic fungi play important roles during the infection process of fungal pathogens onto their host plants. However, the molecular mechanisms by which R. solani effectors regulate rice immunity are not well understood. Through prediction, 78 candidate effector molecules were identified. Using the tobacco rattle virus-host induced gene silencing(TRV-HIGS) system, 45 RNAi constructs of effector genes were infiltrated into Nicotiana benthamiana leaves. The results revealed that eight of these constructs resulted in a significant reduction in necrosis caused by infection with the AG1-IA strain GD-118. Additionally, stable rice transformants carrying the double-stranded RNA construct for one of the effector genes, AGLIP1, were generated to further verify the function of this gene. The suppression of the AGLIP1 gene increased the resistance of both N. benthamiana and rice against GD-118, and also affected the growth rate of GD-118, indicating that AGLIP1 is a key pathogenic factor. Small RNA sequencing showed that the HIGS vectors were processed into si RNAs within the plants and then translocated to the fungi, leading to the silencing of the target genes. As a result, AGLIP1 might be an excellent candidate for HIGS, thereby enhancing crop resistance against the pathogen and contributing to the control of R. solani infection.展开更多
Pear is a fruit crop of worldwide importance and cold storage is an integral part of the production and distribution of pears.An uncharacterized fungal disease has been observed on‘Huangguan’pear fruit during cold s...Pear is a fruit crop of worldwide importance and cold storage is an integral part of the production and distribution of pears.An uncharacterized fungal disease has been observed on‘Huangguan’pear fruit during cold storage in Hebei Province.The fungus was consistently isolated from diseased fruit by routine tissue separation method,and shown to be the causal agent according to Koch postulates.Based on its morphology,molecular characteristics,pathogenicity and ITS sequence,the fungus was identified as Rhizoctonia solani.This study recorded postharvest fruit rot caused by Rhizoctonia solani on pear fruit in China.展开更多
BACKGROUND Coronavirus disease 2019(COVID-19)-associated invasive pulmonary aspergillosis presents a diagnostic challenge due to its non-specific clinical/imaging features,as well as the fact that the proposed clinica...BACKGROUND Coronavirus disease 2019(COVID-19)-associated invasive pulmonary aspergillosis presents a diagnostic challenge due to its non-specific clinical/imaging features,as well as the fact that the proposed clinically diagnostic algorithms do not necessarily apply to COVID-19 patients.In addition,Fusarium spp.is a rare cause of opportunistic life-threatening fungal infections.Disseminated Fusarium infection in an immunocompromised host is intractable,with a high likelihood of resulting mortality.To our knowledge,this is the first case of secondary pulmonary infection by Fusarium solani(F.solani)and Aspergillus niger(A.niger)during systemic steroid treatment for COVID-19.CASE SUMMARY A 62-year-old male was transported to our hospital by ambulance with a complaint of fever and dyspnea.We established a diagnosis of pneumococcal pneumonia,complicated with COVID-19 and septic shock,together with acute renal failure.He was admitted to the intensive care unit,to be treated with piperacillin/tazobactam,vancomycin,and 6.6 mg per day of dexamethasone sodium phosphate,along with noradrenaline as a vasopressor,ventilator management,and continuous hemodiafiltration.His condition improved,and we finished the vasopressor on the fifth hospital day.We administered dexamethasone for ten days,and finished the course of treatment.On the eleventh day,patient respiratory deterioration was observed,and a computed tomography scan showed an exacerbation of bilateral ground-glass-opacity-like consolidation,together with newly appeared cavitary lesions in the lung.we changed antibiotics to meropenem plus vancomycin.In addition,a fungal infection was considered as a possibility based on microscopic findings of sputum,and we began coadministration of voriconazole.However,the pneumonia worsened,and the patient died on the seventeenth day of illness.Later,F.solani and A.niger were identified from sputum collected on the twelfth day.It was believed that he developed a cell-mediated immune deficiency during COVID-19 treatment,which led to the complication of pneumonia caused by the above-mentioned fungi,contributing to his death.CONCLUSION Because early initiation of intense antifungal therapy offers the best chance for survival in pulmonary fusariosis,computed tomography scans and appropriate microbiologic investigations should be obtained for severely immunocompromised patients.展开更多
基金supported by the Earmarked Fund for the China Agriculture Research System(CARS-27)the Key Science and Technology Special Projects of Shaanxi Province,China(2020zdzx03-01-02).
文摘Apple replant disease(ARD)has led to severe yield and quality reduction in the apple industry.Fusarium solani(F.solani)has been identified as one of the main microbial pathogens responsible for ARD.Auxin(indole-3-acetic acid,IAA),an endogenous hormone in plants,is involved in almost all plant growth and development processes and plays a role in plant immunity against pathogens.Gretchen Hagen3(GH3)is one of the early/primary auxin response genes.The aim of this study was to evaluate the function of MdGH3-2 and MdGH3-12 in the defense response of F.solani by treating MdGH3-2/12 RNAi plants with F.solani.The results show that under F.solani infection,RNAi of MdGH3-2/12 inhibited plant biomass accumulation and exacerbated root damage.After inoculation with F.solani,MdGH3-2/12 RNAi inhibited the biosynthesis of acid-amido synthetase.This led to the inhibition of free IAA combining with amino acids,resulting in excessive free IAA accumulation.This excessive free IAA altered plant tissue structure,accelerated fungal hyphal invasion,reduced the activity of antioxidant enzymes(SOD,POD and CAT),increased the reactive oxygen species(ROS)level,and reduced total chlorophyll content and photosynthetic ability,while regulating the expression of PR-related genes including PR1,PR4,PR5 and PR8.It also changed the contents of plant hormones and amino acids,and ultimately reduced the resistance to F.solani.In conclusion,these results demonstrate that MdGH3-2 and MdGH3-12 play an important role in apple tolerance to F.solani and ARD.
基金supported by the Henan Province Science and Technology Research Project, China (Grant No. 242102110232)the National Natural Science Foundation of China (Grant No. 31801677)the Major Program of Guangdong Basic and Applied Basic Research, China (Grant No. 2019B030302006)。
文摘Rice sheath blight, caused by Rhizoctonia solani AG1-IA, is a major disease in rice-growing areas worldwide. Effectors of phytopathogenic fungi play important roles during the infection process of fungal pathogens onto their host plants. However, the molecular mechanisms by which R. solani effectors regulate rice immunity are not well understood. Through prediction, 78 candidate effector molecules were identified. Using the tobacco rattle virus-host induced gene silencing(TRV-HIGS) system, 45 RNAi constructs of effector genes were infiltrated into Nicotiana benthamiana leaves. The results revealed that eight of these constructs resulted in a significant reduction in necrosis caused by infection with the AG1-IA strain GD-118. Additionally, stable rice transformants carrying the double-stranded RNA construct for one of the effector genes, AGLIP1, were generated to further verify the function of this gene. The suppression of the AGLIP1 gene increased the resistance of both N. benthamiana and rice against GD-118, and also affected the growth rate of GD-118, indicating that AGLIP1 is a key pathogenic factor. Small RNA sequencing showed that the HIGS vectors were processed into si RNAs within the plants and then translocated to the fungi, leading to the silencing of the target genes. As a result, AGLIP1 might be an excellent candidate for HIGS, thereby enhancing crop resistance against the pathogen and contributing to the control of R. solani infection.
基金supported by the National Key R&D Program of China(Grant No.2016YFD0400903–06)the earmarked fund for China Agriculture Research System(Grant No.CARS-29–19)the Agricultural Science and Technology Innovation Program of Chinese Academy of Agricultural Sciences。
文摘Pear is a fruit crop of worldwide importance and cold storage is an integral part of the production and distribution of pears.An uncharacterized fungal disease has been observed on‘Huangguan’pear fruit during cold storage in Hebei Province.The fungus was consistently isolated from diseased fruit by routine tissue separation method,and shown to be the causal agent according to Koch postulates.Based on its morphology,molecular characteristics,pathogenicity and ITS sequence,the fungus was identified as Rhizoctonia solani.This study recorded postharvest fruit rot caused by Rhizoctonia solani on pear fruit in China.
文摘BACKGROUND Coronavirus disease 2019(COVID-19)-associated invasive pulmonary aspergillosis presents a diagnostic challenge due to its non-specific clinical/imaging features,as well as the fact that the proposed clinically diagnostic algorithms do not necessarily apply to COVID-19 patients.In addition,Fusarium spp.is a rare cause of opportunistic life-threatening fungal infections.Disseminated Fusarium infection in an immunocompromised host is intractable,with a high likelihood of resulting mortality.To our knowledge,this is the first case of secondary pulmonary infection by Fusarium solani(F.solani)and Aspergillus niger(A.niger)during systemic steroid treatment for COVID-19.CASE SUMMARY A 62-year-old male was transported to our hospital by ambulance with a complaint of fever and dyspnea.We established a diagnosis of pneumococcal pneumonia,complicated with COVID-19 and septic shock,together with acute renal failure.He was admitted to the intensive care unit,to be treated with piperacillin/tazobactam,vancomycin,and 6.6 mg per day of dexamethasone sodium phosphate,along with noradrenaline as a vasopressor,ventilator management,and continuous hemodiafiltration.His condition improved,and we finished the vasopressor on the fifth hospital day.We administered dexamethasone for ten days,and finished the course of treatment.On the eleventh day,patient respiratory deterioration was observed,and a computed tomography scan showed an exacerbation of bilateral ground-glass-opacity-like consolidation,together with newly appeared cavitary lesions in the lung.we changed antibiotics to meropenem plus vancomycin.In addition,a fungal infection was considered as a possibility based on microscopic findings of sputum,and we began coadministration of voriconazole.However,the pneumonia worsened,and the patient died on the seventeenth day of illness.Later,F.solani and A.niger were identified from sputum collected on the twelfth day.It was believed that he developed a cell-mediated immune deficiency during COVID-19 treatment,which led to the complication of pneumonia caused by the above-mentioned fungi,contributing to his death.CONCLUSION Because early initiation of intense antifungal therapy offers the best chance for survival in pulmonary fusariosis,computed tomography scans and appropriate microbiologic investigations should be obtained for severely immunocompromised patients.
