Three genes encoding for fungal cell wall degrading enzymes (CWDEs), ech42, nag70 and gluc78 from the biocontrol fungus Trichoderma atroviride were inserted into the binary vector pCAMBIA1305.2 singly and in all possi...Three genes encoding for fungal cell wall degrading enzymes (CWDEs), ech42, nag70 and gluc78 from the biocontrol fungus Trichoderma atroviride were inserted into the binary vector pCAMBIA1305.2 singly and in all possible combinations and transformed to rice plants. More than 1800 independently regenerated plantlets in seven different populations (for each of the three genes and each of the four gene combinations) were obtained. The ech42 gene encoding for an endochitinase increased resistance to sheath blight caused by Rhizoctonia solani, while the exochitinase-encoding gene, nag70, had lesser effect. The expression level of endochitinase but exochitinase was correlated with disease resistance. Nevertheless, exochitinase enhanced the effect of endochitinase on disease resistance when the two genes co-expressed in transgenics. Resistance to Magnaporthe grisea was found in all kinds of regenerated plants including that with single gluc78. A few lines expressing either ech42 or nag70 gene were immune to the disease. Transgenic plants are being tested to further evaluate disease resistance at field level. This is the first report of multiple of expression of genes encoding CWDEs from Trichoderma atroviride that result in resistance to blast and sheath blight in rice.展开更多
Excessive use of organophosphate pesticides(OP),such as dichlorvos,in farming system poses a threat to human health through potential contamination of environment.To date,biodegradation has been prospected most promis...Excessive use of organophosphate pesticides(OP),such as dichlorvos,in farming system poses a threat to human health through potential contamination of environment.To date,biodegradation has been prospected most promising approach to eliminate environmental OP residues.Trichoderma species as a biological control microorganism is often exposed to the chemical pesticides applied in environments,so it is necessary to understand the mechanism of degradation of dichlorvos by Trichoderma.In this study,dichlorvos significantly inhibited the growth,sporulation and pigmentation of T.atroviride T23,and the dichlorvos degradation activity of T23 required the initial induction effect of dichlorvos and the culture conditions,including the nutrient and pH values of the medium.Various changed primary and secondary metabolites released from T23 in the presence of dichlorvos were speculated as the energy and antioxidants for the strain itself to tolerate dichlorvos stress.The results showed that T23 could produce a series of enzymes,especially the intracellular enzymes,to degrade dichlorvos.The activities of the intracellular enzyme generated by T23 were differentially changed along time course and especially relied on initial dichlorvos concentration,ammonium sulfate and phosphate added in the medium.In conclusion,some dichlorvos-induced chemical degradation related enzymes of T23 were proved to be involved in the degradation of dichlorvos.展开更多
基金Project (No.3997002) supported by the National Natural Science Foundation of China
文摘Three genes encoding for fungal cell wall degrading enzymes (CWDEs), ech42, nag70 and gluc78 from the biocontrol fungus Trichoderma atroviride were inserted into the binary vector pCAMBIA1305.2 singly and in all possible combinations and transformed to rice plants. More than 1800 independently regenerated plantlets in seven different populations (for each of the three genes and each of the four gene combinations) were obtained. The ech42 gene encoding for an endochitinase increased resistance to sheath blight caused by Rhizoctonia solani, while the exochitinase-encoding gene, nag70, had lesser effect. The expression level of endochitinase but exochitinase was correlated with disease resistance. Nevertheless, exochitinase enhanced the effect of endochitinase on disease resistance when the two genes co-expressed in transgenics. Resistance to Magnaporthe grisea was found in all kinds of regenerated plants including that with single gluc78. A few lines expressing either ech42 or nag70 gene were immune to the disease. Transgenic plants are being tested to further evaluate disease resistance at field level. This is the first report of multiple of expression of genes encoding CWDEs from Trichoderma atroviride that result in resistance to blast and sheath blight in rice.
基金supported by the National Natural Science Foundation of China(31872015)the Shanghai Science and Technology Innovation Action Program of the Shanghai Science and Technology Commission,China(21N41900200)+2 种基金the Shanghai Agricultural Applied Technology Development Program(2022-02-08-00-12-F0-01143)the China Agriculture Research System of MOF and MARA(CARS-02)the National Key R&D Program of China(2017YFD0200403).
文摘Excessive use of organophosphate pesticides(OP),such as dichlorvos,in farming system poses a threat to human health through potential contamination of environment.To date,biodegradation has been prospected most promising approach to eliminate environmental OP residues.Trichoderma species as a biological control microorganism is often exposed to the chemical pesticides applied in environments,so it is necessary to understand the mechanism of degradation of dichlorvos by Trichoderma.In this study,dichlorvos significantly inhibited the growth,sporulation and pigmentation of T.atroviride T23,and the dichlorvos degradation activity of T23 required the initial induction effect of dichlorvos and the culture conditions,including the nutrient and pH values of the medium.Various changed primary and secondary metabolites released from T23 in the presence of dichlorvos were speculated as the energy and antioxidants for the strain itself to tolerate dichlorvos stress.The results showed that T23 could produce a series of enzymes,especially the intracellular enzymes,to degrade dichlorvos.The activities of the intracellular enzyme generated by T23 were differentially changed along time course and especially relied on initial dichlorvos concentration,ammonium sulfate and phosphate added in the medium.In conclusion,some dichlorvos-induced chemical degradation related enzymes of T23 were proved to be involved in the degradation of dichlorvos.
