Testing the Efficacy of Nanoparticles, Biological Formulation with the qPCR Technique to Improve HLB Management
Shloke Patel · International journal of high school research · 2022
Citrus phloem bacteria, Candidatus Liberibacter asiaticus (CLas), causes the citrus greening disease, Huanglongbing (HLB).In 2019, this devastating disease caused a 21% decrease in the fresh citrus fruit market and a 72% decline in the commercially grown production of oranges in Florida.The number of Florida industry jobs dropped by 59% compared to previous years.HLB has no cure; global orange juice production is expected to fall by double digits in the coming years.Typical symptoms include yellowing of the leaves, as well as lopsided, premature, and bitter fruits.Since, CLas hides deep within the citrus phloem, commercial antibiotic sprays often cannot reach the bacteria.A biological solution for the prevention of the detrimental effects of HLB was used; the formulations tested were combined with copper nanoparticles which would potentially increase the penetration and the longevity of the formulation to mitigate the effects of the greening disease.The formulations included Firewall and Fireline, two approved and readily available antibacterial solutions, and a bioformulation, curry leaf extract.The experiment was conducted in a greenhouse with 42 infected plants with five leaf samples being collected from each plant.The DNA of the leaves was extracted using the GeneJET DNA purification Kit.6 formulations: Firewall with and without nanoparticles, Fireline with and without nanoparticles, curry leaf extracted with and without nanoparticles were prepared and injected into six plants.After 3 months, the bacterial DNA concentration was determined, and 4 physical parameters of the plant were measured.The formulations were injected again, and after 70 days, qPCR assay and physical parameters were measured.Then, both the CT values and physical parameters were collected and compared.The bacterial count remained unchanged in the treatment and control variables, the three physical parameters, trunk diameter, plant height, and width all improved compared to the control variable.