This review presents the development of researches on arbuscular mycorrhizae(AM)conducted in Cuba,a tropical Caribbean island rich in biodiversity.The key findings from this work are highlighted and presented as a ste...This review presents the development of researches on arbuscular mycorrhizae(AM)conducted in Cuba,a tropical Caribbean island rich in biodiversity.The key findings from this work are highlighted and presented as a stepping stone for future research.Cuban research has contributed to understand the diversity and functionality of AM in several tropical ecosystems,mainly evergreen forests,agroecosystems,sand dunes and pasturelands.Inventories were conducted in 10 out of 16 provinces reported 79 AM species,representing 25%of the known species worldwide.Cuban researchers have a great deal of expertise in Glomeromycota taxonomy and have described 11 new species,of which six were not reported elsewhere in the world.Furthermore,important studies conducted in Cuba have shed light on the mycotrophic plants,the role of AM in forest ecosystems,and their use in crop production.The contribution of AM to ecosystem processes is a priority line of research.Interdisciplinary and multidisciplinary researches are necessary to define the role of AM symbioses and improve biogeochemical models.Recently created Cuban Mycorrhizal Research Network will help to coordinate validation campaigns for various biofertilizers with training courses for Cuban farmers to disseminate the key results on AM.Despite the challenges for Cuban mycorrhizologists,molecular(genomic)techniques,stable isotopes and nuclear magnetic resonance should also be included as priority lines of research in the future.展开更多
Background Subclinical mastitis,caused by many pathogens including Staphylococcus aureus(S.aureus)and Staphylococcus chromogenes(S.chromogenes),presents a major challenge to the dairy industry due to its associated ec...Background Subclinical mastitis,caused by many pathogens including Staphylococcus aureus(S.aureus)and Staphylococcus chromogenes(S.chromogenes),presents a major challenge to the dairy industry due to its associated economic losses and poor milk quality.The molecular regulatory mechanisms,including the role of small nucleolar RNAs(snoRNAs),of the host response to mastitis pathogens remain unclear.Therefore,this study investigated snoRNA expression and potential roles during subclinical mastitis.Milk somatic cells from cows with naturally occurring S.aureus(n=14)and S.chromogenes(n=3)subclinical mastitis,and healthy cows(n=4)were subjected to transcriptome sequencing and bioinformatics analyses.Results We identified 255 expressed snoRNAs including 21 differentially expressed(DE)in S.aureus-positive cows and 20 DE in S.chromogenes-positive cows.Prediction of ribosomal RNA(rRNA)modification sites found several 18S rRNA and 28S rRNA modification(pseudouridylation and 2′-O-methylation)target sites essential for ribosome function for DE snoRNAs,such as SNORA79(18S-1319,28S-3001),SNORA1(18S-1496,28S-1747),suggesting their roles in translation and immune modulation during subclinical mastitis.Correlation analysis identified DE snoRNAs-mRNAs(from the same samples)pairs with majority of the correlated mRNAs(e.g.,CXCL8,IL6R,IL2,IL1R,IL18R1,STAT3,NFKB2,MYD88,VEGFA,and CD40)having immune related functions.Functional enrichment of correlated genes of snoRNAs for S.aureus-positive group(regulation of defense/immune response,leukocyte differentiation,response to cytokine,NF-κB signaling pathway,JAK-STAT signaling pathway etc.)and S.chromogenes-positive group(e.g.,regulation of defense response,response to cytokine,regulation of immune response,NF-κB signaling pathway,TNF signaling pathway,and JAK-STAT signaling pathway)revealed involvement in immune and inflammatory processes.Some functional terms were common to both pathogens(e.g.,NF-κB,JAK-STAT signaling,immune system processes)and suggest common regulatory mechanisms used by both pathogens to contain infection.Furthermore,snoRNA-mRNA network construction identified 7 key(hub)snoRNAs each for S.aureus-positive group(SNORA66,novelsnoRNA_26_14905(also denoted as novelSnoRNA_86),SNORD107,SNORA1,SNORA63,SNORA79,SNORA76)and S.chromogenes-positive group(SNORD18,SNORA79,SNORA46,U2-19,SNORA66,SNORD37,SNORD49)that correlated with the most protein coding genes(|r|>0.9;≥30 mRNAs).Functional enrichment of correlated genes of hub snoRNAs reveals their involvement in immune related functions(75%of enriched terms)and metabolic processes(20%of enriched terms).Conclusion These data suggest potential regulatory roles for the DE snoRNAs and in particular,the 14 hub snoRNAs during subclinical mastitis.This study presents the first evidence linking snoRNAs to bovine subclinical mastitis and offers new insights into the molecular mechanisms underlying subclinical mastitis caused by S.aureus and S.chromogenes.展开更多
Background:Mastitis caused by different pathogens including Streptococcus uberis(S.uberis)is responsible for huge economic losses to the dairy industry.In order to investigate the potential genetic and epigenetic regu...Background:Mastitis caused by different pathogens including Streptococcus uberis(S.uberis)is responsible for huge economic losses to the dairy industry.In order to investigate the potential genetic and epigenetic regulatory mecha‑nisms of subclinical mastitis due to S.uberis,the DNA methylome(whole genome DNA methylation sequencing)and transcriptome(RNA sequencing)of milk somatic cells from cows with naturally occurring S.uberis subclinical mastitis and healthy control cows(n=3/group)were studied.Results:Globally,the DNA methylation levels of CpG sites were low in the promoters and first exons but high in inner exons and introns.The DNA methylation levels at the promoter,first exon and first intron regions were nega‑tively correlated with the expression level of genes at a whole‑genome‑wide scale.In general,DNA methylation level was lower in S.uberis‑positive group(SUG)than in the control group(CTG).A total of 174,342 differentially methylated cytosines(DMCs)(FDR<0.05)were identified between SUG and CTG,including 132,237,7412 and 34,693 DMCs in the context of CpG,CHG and CHH(H=A or T or C),respectively.Besides,101,612 methylation haplotype blocks(MHBs)were identified,including 451 MHBs that were significantly different(dMHB)between the two groups.A total of 2130 differentially expressed(DE)genes(1378 with up‑regulated and 752 with down‑regulated expression)were found in SUG.Integration of methylome and transcriptome data with MethGET program revealed 1623 genes with signifi‑cant changes in their methylation levels and/or gene expression changes(MetGDE genes,MethGET P‑value<0.001).Functional enrichment of genes harboring≥15 DMCs,DE genes and MetGDE genes suggest significant involvement of DNA methylation changes in the regulation of the host immune response to S.uberis infection,especially cytokine activities.Furthermore,discriminant correlation analysis with DIABLO method identified 26 candidate biomarkers,including 6 DE genes,15 CpG‑DMCs and 5 dMHBs that discriminated between SUG and CTG.Conclusion:The integration of methylome and transcriptome of milk somatic cells suggests the possible involve‑ment of DNA methylation changes in the regulation of the host immune response to subclinical mastitis due to S.uberis.The presented genetic and epigenetic biomarkers could contribute to the design of management strategies of subclinical mastitis and breeding for mastitis resistance.展开更多
Cranberry (Vaccinium macrocarpon Ait.) is an ammophilous plant grown on acid soils (pH 4.0 - 5.5). Elemental sulfur is commonly applied at a recommended rate of 1120 kg S ha<sup>−1</sup> per pH unit to aci...Cranberry (Vaccinium macrocarpon Ait.) is an ammophilous plant grown on acid soils (pH 4.0 - 5.5). Elemental sulfur is commonly applied at a recommended rate of 1120 kg S ha<sup>−1</sup> per pH unit to acidify cranberry soils, potentially impacting the plant mineral nutrition. The general recommendation may not fit all conditions encountered in the field. Our objective was to develop an equation to predict the sulfur requirement to reach pH<sub>water</sub> of 4.2 to tackle nitrification in acidic cranberry soils varying in initial pH values, and to measure the effect of elemental sulfur on the mineral nutrition and the performance of cranberry crops. A 3-yr experiment was designed to test the effect of elemental sulfur on soil and tissue tests and on berry yield and quality. Four S treatments (0, 250, 500 and 1000 kg S ha<sup>−1</sup>) were established on three duplicated sites during two consecutive years. We ran soil, foliar tissue, berry tissue tests, and measured berry yield, size, anthocyanin content (TAcy), Brix, and firmness. Nutrients were expressed as centered log ratios to reflect nutrient interactions. Results were analyzed using a mixed model. Soil Ca decreased while soil Mn and S increased significantly (p ≤ 0.05). Sulfur showed no significant effects on nutrient balances in uprights. The S impacted negatively berry B balance, and positively berry Mn and S balances. A linear regression model relating pH change to S dosage and elapsed time (R<sup>2</sup> = 0.53) showed that to reach pH<sub>water</sub> of 4.2 two years after S application, 250 - 1000 kg S ha<sup>−1</sup> could be applied depending on initial soil pH value. The stratification of surface-applied elemental S in the soil profile should be further examined in relation to plant rooting and nutrient leaching.展开更多
Background Mastitis caused by multiple factors remains one of the most common and costly disease of the dairy industry.Multi-omics approaches enable the comprehensive investigation of the complex interactions between ...Background Mastitis caused by multiple factors remains one of the most common and costly disease of the dairy industry.Multi-omics approaches enable the comprehensive investigation of the complex interactions between mul-tiple layers of information to provide a more holistic view of disease pathogenesis.Therefore,this study investigated the genomic and epigenomic signatures and the possible regulatory mechanisms underlying subclinical mastitis by integrating RNA sequencing data(mRNA and lncRNA),small RNA sequencing data(miRNA)and DNA methylation sequencing data of milk somatic cells from 10 healthy cows and 20 cows with naturally occurring subclinical mastitis caused by Staphylococcus aureus or Staphylococcus chromogenes.Results Functional investigation of the data sets through gene set analysis uncovered 3458 biological process GO terms and 170 KEGG pathways with altered activities during subclinical mastitis,provided further insights into subclin-ical mastitis and revealed the involvement of multi-omics signatures in the altered immune responses and impaired mammary gland productivity during subclinical mastitis.The abundant genomic and epigenomic signatures with sig-nificant alterations related to subclinical mastitis were observed,including 30,846,2552,1276 and 57 differential methylation haplotype blocks(dMHBs),differentially expressed genes(DEGs),lncRNAs(DELs)and miRNAs(DEMs),respectively.Next,5 factors presenting the principal variation of differential multi-omics signatures were identified.The important roles of Factor 1(DEG,DEM and DEL)and Factor 2(dMHB and DEM),in the regulation of immune defense and impaired mammary gland functions during subclinical mastitis were revealed.Each of the omics within Factors 1 and 2 explained about 20%of the source of variation in subclinical mastitis.Also,networks of impor-tant functional gene sets with the involvement of multi-omics signatures were demonstrated,which contributed to a comprehensive view of the possible regulatory mechanisms underlying subclinical mastitis.Furthermore,multi-omics integration enabled the association of the epigenomic regulatory factors(dMHBs,DELs and DEMs)of altered genes in important pathways,such as‘Staphylococcus aureus infection pathway’and‘natural killer cell mediated cyto-toxicity pathway’,etc.,which provides further insights into mastitis regulatory mechanisms.Moreover,few multi-omics signatures(14 dMHBs,25 DEGs,18 DELs and 5 DEMs)were identified as candidate discriminant signatures with capac-ity of distinguishing subclinical mastitis cows from healthy cows.Conclusion The integration of genomic and epigenomic data by multi-omics approaches in this study provided a better understanding of the molecular mechanisms underlying subclinical mastitis and identified multi-omics candidate discriminant signatures for subclinical mastitis,which may ultimately lead to the development of more effective mastitis control and management strategies.展开更多
Background:Winter climate change including frequent freeze-thaw episodes and shallow snow cover will have major impacts on the spring regrowth of perennial crops.Non-bloating perennial forage legume species including ...Background:Winter climate change including frequent freeze-thaw episodes and shallow snow cover will have major impacts on the spring regrowth of perennial crops.Non-bloating perennial forage legume species including sainfoin,birdsfoot trefoil,red clover,and alsike clover have been bred for their adaptation to harsh winter conditions.In parallel,the selection of cold-tolerant rhizobial strains could allow earlier symbiotic nitrogen(N)fixation to hasten spring regrowth of legumes.Methods:To identify strains forming nodules rapidly and showing high N-fixing potential,60 rhizobial strains in association with four temperate legume species were evaluated over 11 weeks under spring soil temperatures for kinetics of nodule formation,nitrogenase activity,and host yield.Results:Strains differed in their capacity to form efficient nodules on legume hosts over time.Strains showing higher nitrogenase activity were arctic strain N10 with sainfoin and strain L2 with birdsfoot trefoil.For clovers,nitrogenase activity was similar for control and inoculated plants,likely due to formation of effective nodules in controls by endophyte rhizobia present in seeds.Conclusions:Selection based on nodulation kinetics at low temperature,nitrogenase activity,and yield was effective to identify performant rhizobial strains for legume crops.The use of cold-tolerant strains could help mitigate winter climatic changes.展开更多
基金Conselho Nacional de Desenvolvimento Científico e Tecnológico(CNPq)that provided research grants to BT Goto(proc.311945/2019-8)and MB Queiroz.
文摘This review presents the development of researches on arbuscular mycorrhizae(AM)conducted in Cuba,a tropical Caribbean island rich in biodiversity.The key findings from this work are highlighted and presented as a stepping stone for future research.Cuban research has contributed to understand the diversity and functionality of AM in several tropical ecosystems,mainly evergreen forests,agroecosystems,sand dunes and pasturelands.Inventories were conducted in 10 out of 16 provinces reported 79 AM species,representing 25%of the known species worldwide.Cuban researchers have a great deal of expertise in Glomeromycota taxonomy and have described 11 new species,of which six were not reported elsewhere in the world.Furthermore,important studies conducted in Cuba have shed light on the mycotrophic plants,the role of AM in forest ecosystems,and their use in crop production.The contribution of AM to ecosystem processes is a priority line of research.Interdisciplinary and multidisciplinary researches are necessary to define the role of AM symbioses and improve biogeochemical models.Recently created Cuban Mycorrhizal Research Network will help to coordinate validation campaigns for various biofertilizers with training courses for Cuban farmers to disseminate the key results on AM.Despite the challenges for Cuban mycorrhizologists,molecular(genomic)techniques,stable isotopes and nuclear magnetic resonance should also be included as priority lines of research in the future.
基金Agriculture and Agri-Food Canada funded this research(grant number J-002223).
文摘Background Subclinical mastitis,caused by many pathogens including Staphylococcus aureus(S.aureus)and Staphylococcus chromogenes(S.chromogenes),presents a major challenge to the dairy industry due to its associated economic losses and poor milk quality.The molecular regulatory mechanisms,including the role of small nucleolar RNAs(snoRNAs),of the host response to mastitis pathogens remain unclear.Therefore,this study investigated snoRNA expression and potential roles during subclinical mastitis.Milk somatic cells from cows with naturally occurring S.aureus(n=14)and S.chromogenes(n=3)subclinical mastitis,and healthy cows(n=4)were subjected to transcriptome sequencing and bioinformatics analyses.Results We identified 255 expressed snoRNAs including 21 differentially expressed(DE)in S.aureus-positive cows and 20 DE in S.chromogenes-positive cows.Prediction of ribosomal RNA(rRNA)modification sites found several 18S rRNA and 28S rRNA modification(pseudouridylation and 2′-O-methylation)target sites essential for ribosome function for DE snoRNAs,such as SNORA79(18S-1319,28S-3001),SNORA1(18S-1496,28S-1747),suggesting their roles in translation and immune modulation during subclinical mastitis.Correlation analysis identified DE snoRNAs-mRNAs(from the same samples)pairs with majority of the correlated mRNAs(e.g.,CXCL8,IL6R,IL2,IL1R,IL18R1,STAT3,NFKB2,MYD88,VEGFA,and CD40)having immune related functions.Functional enrichment of correlated genes of snoRNAs for S.aureus-positive group(regulation of defense/immune response,leukocyte differentiation,response to cytokine,NF-κB signaling pathway,JAK-STAT signaling pathway etc.)and S.chromogenes-positive group(e.g.,regulation of defense response,response to cytokine,regulation of immune response,NF-κB signaling pathway,TNF signaling pathway,and JAK-STAT signaling pathway)revealed involvement in immune and inflammatory processes.Some functional terms were common to both pathogens(e.g.,NF-κB,JAK-STAT signaling,immune system processes)and suggest common regulatory mechanisms used by both pathogens to contain infection.Furthermore,snoRNA-mRNA network construction identified 7 key(hub)snoRNAs each for S.aureus-positive group(SNORA66,novelsnoRNA_26_14905(also denoted as novelSnoRNA_86),SNORD107,SNORA1,SNORA63,SNORA79,SNORA76)and S.chromogenes-positive group(SNORD18,SNORA79,SNORA46,U2-19,SNORA66,SNORD37,SNORD49)that correlated with the most protein coding genes(|r|>0.9;≥30 mRNAs).Functional enrichment of correlated genes of hub snoRNAs reveals their involvement in immune related functions(75%of enriched terms)and metabolic processes(20%of enriched terms).Conclusion These data suggest potential regulatory roles for the DE snoRNAs and in particular,the 14 hub snoRNAs during subclinical mastitis.This study presents the first evidence linking snoRNAs to bovine subclinical mastitis and offers new insights into the molecular mechanisms underlying subclinical mastitis caused by S.aureus and S.chromogenes.
文摘Background:Mastitis caused by different pathogens including Streptococcus uberis(S.uberis)is responsible for huge economic losses to the dairy industry.In order to investigate the potential genetic and epigenetic regulatory mecha‑nisms of subclinical mastitis due to S.uberis,the DNA methylome(whole genome DNA methylation sequencing)and transcriptome(RNA sequencing)of milk somatic cells from cows with naturally occurring S.uberis subclinical mastitis and healthy control cows(n=3/group)were studied.Results:Globally,the DNA methylation levels of CpG sites were low in the promoters and first exons but high in inner exons and introns.The DNA methylation levels at the promoter,first exon and first intron regions were nega‑tively correlated with the expression level of genes at a whole‑genome‑wide scale.In general,DNA methylation level was lower in S.uberis‑positive group(SUG)than in the control group(CTG).A total of 174,342 differentially methylated cytosines(DMCs)(FDR<0.05)were identified between SUG and CTG,including 132,237,7412 and 34,693 DMCs in the context of CpG,CHG and CHH(H=A or T or C),respectively.Besides,101,612 methylation haplotype blocks(MHBs)were identified,including 451 MHBs that were significantly different(dMHB)between the two groups.A total of 2130 differentially expressed(DE)genes(1378 with up‑regulated and 752 with down‑regulated expression)were found in SUG.Integration of methylome and transcriptome data with MethGET program revealed 1623 genes with signifi‑cant changes in their methylation levels and/or gene expression changes(MetGDE genes,MethGET P‑value<0.001).Functional enrichment of genes harboring≥15 DMCs,DE genes and MetGDE genes suggest significant involvement of DNA methylation changes in the regulation of the host immune response to S.uberis infection,especially cytokine activities.Furthermore,discriminant correlation analysis with DIABLO method identified 26 candidate biomarkers,including 6 DE genes,15 CpG‑DMCs and 5 dMHBs that discriminated between SUG and CTG.Conclusion:The integration of methylome and transcriptome of milk somatic cells suggests the possible involve‑ment of DNA methylation changes in the regulation of the host immune response to subclinical mastitis due to S.uberis.The presented genetic and epigenetic biomarkers could contribute to the design of management strategies of subclinical mastitis and breeding for mastitis resistance.
文摘Cranberry (Vaccinium macrocarpon Ait.) is an ammophilous plant grown on acid soils (pH 4.0 - 5.5). Elemental sulfur is commonly applied at a recommended rate of 1120 kg S ha<sup>−1</sup> per pH unit to acidify cranberry soils, potentially impacting the plant mineral nutrition. The general recommendation may not fit all conditions encountered in the field. Our objective was to develop an equation to predict the sulfur requirement to reach pH<sub>water</sub> of 4.2 to tackle nitrification in acidic cranberry soils varying in initial pH values, and to measure the effect of elemental sulfur on the mineral nutrition and the performance of cranberry crops. A 3-yr experiment was designed to test the effect of elemental sulfur on soil and tissue tests and on berry yield and quality. Four S treatments (0, 250, 500 and 1000 kg S ha<sup>−1</sup>) were established on three duplicated sites during two consecutive years. We ran soil, foliar tissue, berry tissue tests, and measured berry yield, size, anthocyanin content (TAcy), Brix, and firmness. Nutrients were expressed as centered log ratios to reflect nutrient interactions. Results were analyzed using a mixed model. Soil Ca decreased while soil Mn and S increased significantly (p ≤ 0.05). Sulfur showed no significant effects on nutrient balances in uprights. The S impacted negatively berry B balance, and positively berry Mn and S balances. A linear regression model relating pH change to S dosage and elapsed time (R<sup>2</sup> = 0.53) showed that to reach pH<sub>water</sub> of 4.2 two years after S application, 250 - 1000 kg S ha<sup>−1</sup> could be applied depending on initial soil pH value. The stratification of surface-applied elemental S in the soil profile should be further examined in relation to plant rooting and nutrient leaching.
基金The help and support of owners of the dairy farms enrolled in this study is gratefully acknowledged.The financial support from the program of China Scholarship Council during the PhD study of Mengqi Wang in Canada is acknowledged(No.202008880009).
文摘Background Mastitis caused by multiple factors remains one of the most common and costly disease of the dairy industry.Multi-omics approaches enable the comprehensive investigation of the complex interactions between mul-tiple layers of information to provide a more holistic view of disease pathogenesis.Therefore,this study investigated the genomic and epigenomic signatures and the possible regulatory mechanisms underlying subclinical mastitis by integrating RNA sequencing data(mRNA and lncRNA),small RNA sequencing data(miRNA)and DNA methylation sequencing data of milk somatic cells from 10 healthy cows and 20 cows with naturally occurring subclinical mastitis caused by Staphylococcus aureus or Staphylococcus chromogenes.Results Functional investigation of the data sets through gene set analysis uncovered 3458 biological process GO terms and 170 KEGG pathways with altered activities during subclinical mastitis,provided further insights into subclin-ical mastitis and revealed the involvement of multi-omics signatures in the altered immune responses and impaired mammary gland productivity during subclinical mastitis.The abundant genomic and epigenomic signatures with sig-nificant alterations related to subclinical mastitis were observed,including 30,846,2552,1276 and 57 differential methylation haplotype blocks(dMHBs),differentially expressed genes(DEGs),lncRNAs(DELs)and miRNAs(DEMs),respectively.Next,5 factors presenting the principal variation of differential multi-omics signatures were identified.The important roles of Factor 1(DEG,DEM and DEL)and Factor 2(dMHB and DEM),in the regulation of immune defense and impaired mammary gland functions during subclinical mastitis were revealed.Each of the omics within Factors 1 and 2 explained about 20%of the source of variation in subclinical mastitis.Also,networks of impor-tant functional gene sets with the involvement of multi-omics signatures were demonstrated,which contributed to a comprehensive view of the possible regulatory mechanisms underlying subclinical mastitis.Furthermore,multi-omics integration enabled the association of the epigenomic regulatory factors(dMHBs,DELs and DEMs)of altered genes in important pathways,such as‘Staphylococcus aureus infection pathway’and‘natural killer cell mediated cyto-toxicity pathway’,etc.,which provides further insights into mastitis regulatory mechanisms.Moreover,few multi-omics signatures(14 dMHBs,25 DEGs,18 DELs and 5 DEMs)were identified as candidate discriminant signatures with capac-ity of distinguishing subclinical mastitis cows from healthy cows.Conclusion The integration of genomic and epigenomic data by multi-omics approaches in this study provided a better understanding of the molecular mechanisms underlying subclinical mastitis and identified multi-omics candidate discriminant signatures for subclinical mastitis,which may ultimately lead to the development of more effective mastitis control and management strategies.
文摘Background:Winter climate change including frequent freeze-thaw episodes and shallow snow cover will have major impacts on the spring regrowth of perennial crops.Non-bloating perennial forage legume species including sainfoin,birdsfoot trefoil,red clover,and alsike clover have been bred for their adaptation to harsh winter conditions.In parallel,the selection of cold-tolerant rhizobial strains could allow earlier symbiotic nitrogen(N)fixation to hasten spring regrowth of legumes.Methods:To identify strains forming nodules rapidly and showing high N-fixing potential,60 rhizobial strains in association with four temperate legume species were evaluated over 11 weeks under spring soil temperatures for kinetics of nodule formation,nitrogenase activity,and host yield.Results:Strains differed in their capacity to form efficient nodules on legume hosts over time.Strains showing higher nitrogenase activity were arctic strain N10 with sainfoin and strain L2 with birdsfoot trefoil.For clovers,nitrogenase activity was similar for control and inoculated plants,likely due to formation of effective nodules in controls by endophyte rhizobia present in seeds.Conclusions:Selection based on nodulation kinetics at low temperature,nitrogenase activity,and yield was effective to identify performant rhizobial strains for legume crops.The use of cold-tolerant strains could help mitigate winter climatic changes.
