The bZIP transcription factor ATF1 regulates blue light and oxidative stress responses in Trichoderma guizhouense

In several filamentous fungi,incident light and environmental stress signaling share the mitogen-activated protein kinase(MAPK)HOG(SAK)pathway.It has been revealed that short-term illumination with blue light triggers the activation of the HOG pathway in Trichoderma spp.In this study,we demonstrate the crucial role of the basic leucine zipper transcription factor ATF1 in blue light responses and signaling downstream of the MAPK HOG1 in Trichoderma guizhouense.The lack of ATF1 severely impaired photoconidiation and delayed vegetative growth and conidial germination.Upon blue light or H2O2 stimuli,HOG1 interacted with ATF1 in the nucleus.Genome-wide transcriptome analyses revealed that 61.8%(509 out of 824)and 85.2%(702 out of 824)of blue light-regulated genes depended on ATF1 and HOG1,respectively,of which 58.4%(481 out of 824)were regulated by both of them.Our results also show that blue light promoted conidial germination and HOG1 and ATF1 played opposite roles in controlling conidial germination in the dark.Additionally,the lack of ATF1 led to reduced oxidative stress resistance,probably because of the downregulation of catalase-encoding genes.Overall,our results demonstrate that ATF1 is the downstream component of HOG1 and is responsible for blue light responses,conidial germination,vegetative growth,and oxidative stress resistance in T.guizhouense.

Decreased nitrous oxide emissions associated with functional microbial genes under bio-organic fertilizer application in vegetable fields

Bio-organic fertilizers enriched with plant growth-promoting microbes(PGPMs)have been widely used in crop fields to promote plant growth and maintain soil microbiome functions.However,their potential effects on N_(2)O emissions are of increasing concern.In this study,an in situ measurement experiment was conducted to investigate the effect of organic fertilizer containing Trichoderma guizhouense(a plant growth-promoting fungus)on soil N_(2)O emissions from a greenhouse vegetable field.The following four treatments were used:no fertilizer(control),chemical fertilizer(NPK),organic fertilizer derived from cattle manure(O),and organic fertilizer containing T.guizhouense(O+T,referring to bio-organic fertilizer).The abundances of soil N cycling-related functional genes(amoA)from ammonium-oxidizing bacteria(AOB)and archaea(AOA),as well as nirS,nirK,and nosZ,were simultaneously determined using quantitative PCR(qPCR).Compared to the NPK plot,seasonal total N_(2)O emissions decreased by 11.7%and 18.7%in the O and O+T plots,respectively,which was attributed to lower NH_(4)^(+)-N content and AOB amoA abundance in the O and O+T plots.The nosZ abundance was significantly greater in the O+T plot,whilst the AOB amoA abundance was significantly lower in the O+T plot than in the O plot.Relative to the organic fertilizer,bio-organic fertilizer application tended to decrease N_(2)O emissions by 7.9%and enhanced vegetable yield,resulting in a significant decrease in yield-scaled N_(2)O emissions.Overall,the results of this study suggested that,compared to organic and chemical fertilizers,bio-organic fertilizers containing PGPMs could benefit crop yield and mitigate N_(2)O emissions in vegetable fields.