The influence of rootstock used in grafted lemon on population and life table parameters of Eutetranychus orientalis (Klein) (Acari: Tetranychidae)

Grafting is a technique greatly used in fruit trees and vegetable crops by joining the rootstock of one plant with the scion of another plant. The rootstock is chosen for its ability to provide the scion with a healthy root system that provides not only higher tolerance to abiotic stress conditions but also a stronger resistance against pests and pathogens. Therefore, this study aimed to evaluate the effects of two commonly used rootstocks, sour orange and volkamer lemon, in lemon grafting on population densities and life table parameters of Eutetranychus orientalis (Klein). The results were then related to the chemical identification of polyphenol compounds using HPLC. Significant changes in population density and life table parameters of E. orientalis were observed between the two rootstocks used in lemon grafting. The rootstock sour orange had a high influence on population growth of E. orientalis. Balady limes and adalia lemons grafted onto sour orange showed lower density of E. orientalis movable stages than balady limes grafted onto volkamer lemon. Balady limes and adalia lemons grafted onto sour orange significantly increased the total developmental periods of E. orientalis and decreased the adult longevity period, oviposition period, and the total fecundity of females. The total developmental period was 9.64 and 10.14 days, the adult longevity period was 3.58 and 3.59 days, and the total fecundity of females was 4.59 and 5.50 eggs/female, respectively. Additionally, the use of sour orange in grafting lemon resulted in a decrease in the net (R0) and gross (GRR) reproductive rates, which in turn reduced the intrinsic (r) and finite (λ) rates of increase. The rootstock's high performance may be attributed to the presence of high concentrations of polyphenol compounds that deter feeding and reproduction by E. orientalis. The study suggests that this rootstock can be utilized as a tool in integrated pest management strategies against the citrus brown mite, E. orientalis. When incorporated into an integrated pest control program for E. orientalis in citrus orchards, this technique enhances plant tolerance to infestation, while also ensuring that the output is effective and sustainable.