Cotton production faces significant challenges from insect pests,with chemical pesticide use becoming increasingly limited by resistance and environmental concerns.This study explores the potential use of caffeine,a n...Cotton production faces significant challenges from insect pests,with chemical pesticide use becoming increasingly limited by resistance and environmental concerns.This study explores the potential use of caffeine,a natural plant alkaloid,as an environmentally friendly insect resistance strategy in cotton.Exogenous caffeine application demonstrated potent insecticidal effects against cotton bollworm(Helicoverpa armigera)larvae,with concentrations≥2 mg mL−1 causing near-complete feeding cessation and up to 70%larval mortality.Building on this,we engineered transgenic cotton(Gossypium hirsutum cv.Jin668)for heterologous caffeine biosynthesis by introducing three key N-methyltransferase genes(CaXMT1,CaMXMT1,CaDXMT1)by multiple gene transformation.Transgenic lines expressing all three genes showed remarkable caffeine accumulation(up to 3.59 mg g−1 dry weight),whereas two-gene combinations exhibited wild-type-level production.Feeding preference assays revealed that caffeine-enriched cotton strongly deterred feeding by H.armigera.Non-choice feeding trials demonstrated reduced leaf consumption and reduced larval growth in H.armigera fed on caffeine-producing cotton.The study highlights the effectiveness of synthetic biology approaches using the TGSII-UNiE multigene stacking system,despite challenges in transgene stability.This work advances plant-derived insect resistance research and provides a sustainable framework for reducing chemical pesticide reliance in cotton production,while underscoring unique potential of cotton as a synthetic biology platform for secondary metabolite engineering.展开更多
柑橘链格孢褐斑病(Alternaria brown spot,ABS)简称柑橘褐斑病,是我国部分橘类和杂交柑橘上新发生的一种重要真菌病害,其病菌可侵染感病柑橘的所有幼嫩组织,果实全生育期均可发病,在利于发病年份,常导致敏感品种大量落叶、落果和枯梢甚...柑橘链格孢褐斑病(Alternaria brown spot,ABS)简称柑橘褐斑病,是我国部分橘类和杂交柑橘上新发生的一种重要真菌病害,其病菌可侵染感病柑橘的所有幼嫩组织,果实全生育期均可发病,在利于发病年份,常导致敏感品种大量落叶、落果和枯梢甚至绝收。然而,迄今尚未有杀菌剂被登记用于该病害的防治。本研究评价了不同杀菌剂单剂、复配剂及杀菌剂组合对2种褐斑病菌菌丝生长的抑制活性、田间防治效果及清园处理效果。结果表明,咯菌腈单剂、氟唑胺·氯氟醚、氟唑菌酰羟胺·咯菌腈、氟酰羟·苯甲唑和嘧环·咯菌腈在有效成分1μg·mL^(-1)时对菌丝生长的抑制率均超过90%;田间药效试验结果表明,氟酰羟·苯甲唑对褐斑病的防治效果较好,且氟唑菌酰羟胺与咯菌腈、代森锰锌混合处理下的防治效果均较好,能够有效降低病梢率和减少落叶数;此外,波尔多液和石硫合剂清园处理可以较好地控制褐斑病,大大降低病梢率。本试验结果为柑橘褐斑病的防治药剂选择提供了数据支持和理论指导。展开更多
基金supported by the National Natural Science Foundation of China (32325039)
文摘Cotton production faces significant challenges from insect pests,with chemical pesticide use becoming increasingly limited by resistance and environmental concerns.This study explores the potential use of caffeine,a natural plant alkaloid,as an environmentally friendly insect resistance strategy in cotton.Exogenous caffeine application demonstrated potent insecticidal effects against cotton bollworm(Helicoverpa armigera)larvae,with concentrations≥2 mg mL−1 causing near-complete feeding cessation and up to 70%larval mortality.Building on this,we engineered transgenic cotton(Gossypium hirsutum cv.Jin668)for heterologous caffeine biosynthesis by introducing three key N-methyltransferase genes(CaXMT1,CaMXMT1,CaDXMT1)by multiple gene transformation.Transgenic lines expressing all three genes showed remarkable caffeine accumulation(up to 3.59 mg g−1 dry weight),whereas two-gene combinations exhibited wild-type-level production.Feeding preference assays revealed that caffeine-enriched cotton strongly deterred feeding by H.armigera.Non-choice feeding trials demonstrated reduced leaf consumption and reduced larval growth in H.armigera fed on caffeine-producing cotton.The study highlights the effectiveness of synthetic biology approaches using the TGSII-UNiE multigene stacking system,despite challenges in transgene stability.This work advances plant-derived insect resistance research and provides a sustainable framework for reducing chemical pesticide reliance in cotton production,while underscoring unique potential of cotton as a synthetic biology platform for secondary metabolite engineering.
文摘柑橘链格孢褐斑病(Alternaria brown spot,ABS)简称柑橘褐斑病,是我国部分橘类和杂交柑橘上新发生的一种重要真菌病害,其病菌可侵染感病柑橘的所有幼嫩组织,果实全生育期均可发病,在利于发病年份,常导致敏感品种大量落叶、落果和枯梢甚至绝收。然而,迄今尚未有杀菌剂被登记用于该病害的防治。本研究评价了不同杀菌剂单剂、复配剂及杀菌剂组合对2种褐斑病菌菌丝生长的抑制活性、田间防治效果及清园处理效果。结果表明,咯菌腈单剂、氟唑胺·氯氟醚、氟唑菌酰羟胺·咯菌腈、氟酰羟·苯甲唑和嘧环·咯菌腈在有效成分1μg·mL^(-1)时对菌丝生长的抑制率均超过90%;田间药效试验结果表明,氟酰羟·苯甲唑对褐斑病的防治效果较好,且氟唑菌酰羟胺与咯菌腈、代森锰锌混合处理下的防治效果均较好,能够有效降低病梢率和减少落叶数;此外,波尔多液和石硫合剂清园处理可以较好地控制褐斑病,大大降低病梢率。本试验结果为柑橘褐斑病的防治药剂选择提供了数据支持和理论指导。
