Natural rubber is an indispensable material of strategic importance that has critical applications in industry and the military.However,the development of the natural rubber industry is impeded by the red root rot dis...Natural rubber is an indispensable material of strategic importance that has critical applications in industry and the military.However,the development of the natural rubber industry is impeded by the red root rot disease of rubber trees caused by Ganoderma pseudoferreum,which is one of the most devastating diseases in the rubber tree growing regions in China.To combat this disease,we screened the antifungal activity of 223 candidate bacterial strains against G.pseudoferreum,and found that Bacillus velezensis strain SF305 exhibited significant antifungal activity against G.pseudoferreum.Bacillus velezensis SF305 had a nearly 70%efficacy against the red root rot disease of rubber trees with the therapeutic treatment(Tre),while it exhibited over 90%protection effectiveness with the preventive treatment(Pre).The underlying biocontrol mechanism revealed that B.velezensis SF305 could reduce the disease severity of red root rot by degrading the mycelia of G.pseudoferreum.An antiSMASH analysis revealed that B.velezensis SF305 contains 15 gene clusters related to secondary metabolite synthesis,13 of which are conserved in species of B.velezensis,but surprisingly,B.velezensis SF305 possesses 2 unique secondary metabolite gene clusters.One is predicted to synthesize locillomycin,and the other is a novel nonribosomal peptides synthetase(NRPS)gene cluster.Genomic analysis showed that B.velezensis SF305 harbors genes involved in motility,chemotaxis,biofilm formation,stress resistance,volatile organic compounds(VOCs)and synthesis of the auxin indole-3-acetic acid(IAA),suggesting its plant growth-promoting rhizobacteria(PGPR)properties.Bacillus velezensis SF305 can promote plant growth and efficiently antagonize some important phytopathogenic fungi and bacteria.This study indicates that B.velezensis SF305 is a versatile plant probiotic bacterium.To the best of our knowledge,this is the first time a B.velezensis strain has been reported as a promising biocontrol agent against the red root rot disease of rubber trees.展开更多
高亲和性铁通透酶FTR1是参与铁元素由胞外转移到胞内过程的重要铁转运蛋白。为了解橡胶树红根病菌(Ganoderma pseudoferreum (Wakef.) V. Over. et Steinm)的高亲和性铁通透酶编码基因GPFTR1,通过同源克隆技术,从橡胶树红根病菌中克隆得...高亲和性铁通透酶FTR1是参与铁元素由胞外转移到胞内过程的重要铁转运蛋白。为了解橡胶树红根病菌(Ganoderma pseudoferreum (Wakef.) V. Over. et Steinm)的高亲和性铁通透酶编码基因GPFTR1,通过同源克隆技术,从橡胶树红根病菌中克隆得到GPFTR1的基因序列,并对其编码的氨基酸序列进行蛋白理化性质分析、保守结构域及跨膜区分析和系统进化树分析,并构建植物表达载体pBIN-GPFTR1-GFP进行该蛋白的亚细胞定位分析。利用生长速率法测定己唑醇和青蒿琥酯对橡胶树红根病菌的抑制率,并在EC50条件下进行橡胶树红根病菌的GPFTR1基因表达分析。结果表明,该基因编码区全长1 191 bp,编码396个氨基酸,推测其分子量为43.23 kD,等电点为6.92,为疏水性蛋白,具有保守基团REXLE和7个跨膜结构域;系统进化树分析显示GPFTR1与紫芝(Ganoderma sinense J. D. Zhao, L. W. Hsu&X. Q. Zhang)同类基因(登录号PIL27756.1)的亲缘关系最近,氨基酸同源性为89%;亚细胞定位结果显示GPFTR1蛋白定位在细胞膜上;生长速率法测定己唑醇和青蒿琥酯EC50分别为0.192 mg/L、26.288 mg/L;实时荧光定量PCR技术检测到GPFTR1蛋白编码基因分别在红根病菌受己唑醇和青蒿琥酯胁迫处理6 h和4 h表达量最高。为进一步研究橡胶树红根病菌GPFTR1基因功能提供了理论参考,对橡胶树红根病的防治具有重要意义。展开更多
基金financially supported by the National Key Research and Development Program of China(2023YFD1200204)the Special Fund for Hainan Excellent Team“Rubber Genetics and Breeding”,China(20210203)。
文摘Natural rubber is an indispensable material of strategic importance that has critical applications in industry and the military.However,the development of the natural rubber industry is impeded by the red root rot disease of rubber trees caused by Ganoderma pseudoferreum,which is one of the most devastating diseases in the rubber tree growing regions in China.To combat this disease,we screened the antifungal activity of 223 candidate bacterial strains against G.pseudoferreum,and found that Bacillus velezensis strain SF305 exhibited significant antifungal activity against G.pseudoferreum.Bacillus velezensis SF305 had a nearly 70%efficacy against the red root rot disease of rubber trees with the therapeutic treatment(Tre),while it exhibited over 90%protection effectiveness with the preventive treatment(Pre).The underlying biocontrol mechanism revealed that B.velezensis SF305 could reduce the disease severity of red root rot by degrading the mycelia of G.pseudoferreum.An antiSMASH analysis revealed that B.velezensis SF305 contains 15 gene clusters related to secondary metabolite synthesis,13 of which are conserved in species of B.velezensis,but surprisingly,B.velezensis SF305 possesses 2 unique secondary metabolite gene clusters.One is predicted to synthesize locillomycin,and the other is a novel nonribosomal peptides synthetase(NRPS)gene cluster.Genomic analysis showed that B.velezensis SF305 harbors genes involved in motility,chemotaxis,biofilm formation,stress resistance,volatile organic compounds(VOCs)and synthesis of the auxin indole-3-acetic acid(IAA),suggesting its plant growth-promoting rhizobacteria(PGPR)properties.Bacillus velezensis SF305 can promote plant growth and efficiently antagonize some important phytopathogenic fungi and bacteria.This study indicates that B.velezensis SF305 is a versatile plant probiotic bacterium.To the best of our knowledge,this is the first time a B.velezensis strain has been reported as a promising biocontrol agent against the red root rot disease of rubber trees.
文摘高亲和性铁通透酶FTR1是参与铁元素由胞外转移到胞内过程的重要铁转运蛋白。为了解橡胶树红根病菌(Ganoderma pseudoferreum (Wakef.) V. Over. et Steinm)的高亲和性铁通透酶编码基因GPFTR1,通过同源克隆技术,从橡胶树红根病菌中克隆得到GPFTR1的基因序列,并对其编码的氨基酸序列进行蛋白理化性质分析、保守结构域及跨膜区分析和系统进化树分析,并构建植物表达载体pBIN-GPFTR1-GFP进行该蛋白的亚细胞定位分析。利用生长速率法测定己唑醇和青蒿琥酯对橡胶树红根病菌的抑制率,并在EC50条件下进行橡胶树红根病菌的GPFTR1基因表达分析。结果表明,该基因编码区全长1 191 bp,编码396个氨基酸,推测其分子量为43.23 kD,等电点为6.92,为疏水性蛋白,具有保守基团REXLE和7个跨膜结构域;系统进化树分析显示GPFTR1与紫芝(Ganoderma sinense J. D. Zhao, L. W. Hsu&X. Q. Zhang)同类基因(登录号PIL27756.1)的亲缘关系最近,氨基酸同源性为89%;亚细胞定位结果显示GPFTR1蛋白定位在细胞膜上;生长速率法测定己唑醇和青蒿琥酯EC50分别为0.192 mg/L、26.288 mg/L;实时荧光定量PCR技术检测到GPFTR1蛋白编码基因分别在红根病菌受己唑醇和青蒿琥酯胁迫处理6 h和4 h表达量最高。为进一步研究橡胶树红根病菌GPFTR1基因功能提供了理论参考,对橡胶树红根病的防治具有重要意义。
