Multicopy nrdB Gene Mediated Molecular Detection of Ca L asiaticus and its management by controlling Diaphorina citri through Tinospora cordifolia

Abstract

quotCa. Liberibacter asiaticus (CLas)quot is the most widely found phloem-restricted gram-negative bacterium in citrus crops causing citrus greening disease in India. Citrus aurantifolia, Citrus sinensis, and Citrus reticulate are the most significant commercial citrus species which account for 41%, 23%, and 23%, respectively, of all citrus fruits produced in India. Since years, Citrus greening disease, commonly referred to as Huanglongbing (HLB), had adverse effect on citrus production. CLas, transmitted by the Asian citrus psyllid, Diaphorina citri (D. citri) is the HLB-causing agent in Asia. Detection of CLas is very challenging because of its low concentration and irregular distribution in its citrus host. A lot of researchers have tried to develop assays based on polymerase chain reaction (PCR), the nrdB gene detection would provide a significant, rapid, and sensitive method to detect the pathogen early in the vector or the citrus plants. This will help in controlling the spread of the disease in non-infected plants, and thus prevent citrus crop loss. The safe and effective management of disease using plant resources has attracted a significant amount of attention due to the rise in insecticide resistance. Tinospora cordifolia (Giloy) is a medicinal plant, and its woody stem contains phytoecdysones, which have been proven to interfere with insect moulting and regulate the life cycle stages of insects. newlineThe objective of the current study was rapid and sensitive molecular detection of Clas bacteria through the specific sets of primer sets for multicopy nrdB gene larger and smaller subunits and to investigate dose dependant effect of T. cordifolia on the survival rate and its modulatory effect on life cycle of D. citri. The present study provides means to detect pathogen in early stages and subsequently stop further dissemination of pathogen thereby helping in the management of Citrus Greening Disease. In this study, a set of PCR primer sets were screened newlinexiv newlineto diagnose CLas through subunits of multic