Avocado ‘Hass’ leaf age affects life table parameters of Oligonychus yothersi (McGregor) (Acari: Tetranychidae) under laboratory conditions

Abstract

The avocado red mite Oligonychus yothersi (McGregor) is the most important avocado (Persea americana Mill.) foliar pest in Chile, infesting 'Hass' avocado between midsummer and late autumn. The post-embryonic development, survival, longevity and life table parameters of O. yothersi were evaluated on both young and mature 'Hass' avocado leaves at 25 ± 0.7 °C, 60 ± 5% relative humidity and 16:8 h photoperiod. The time for larvae, protonymphs and deutonymphs to develop was longer on young leaves than on mature leaves. The immature stage of O. yothersi was shorter (9.29 ± 0.22 d) on mature leaves than on young leaves (14.43 ± 0.28 d); O. yothersi also exhibited higher survival rates for larvae, protonymphs, and deutonymphs on mature leaves. The net reproductive rate (R0) 52.756 ± 1.749 individuals female-1 ; intrinsic rate of increase (rm) 0.241 ± 0.002 female female-1 d-1 , and finite rate of increase (λ) 1.273 ± 0.002 female female-1 of O. yothersi were significantly higher on mature avocado leaves than on young leaves (R0 = 2.727 ± 0.271, rm = 0.049 ± 0.004, and λ = 1.051 ± 0.004). The time required to double the O. yothersi population was only 2.872 ± 0.002 d on mature leaves. Therefore, life table parameters of O. yothersi are negatively affected by young avocado leaves, suggesting that constitutive defenses present in young leaves could affect O. yothersi population parameters.

Galendromus occidentalis (Acari: Phytoseiidae) life table parameters on Oligonychus yothersi (Acari: Tetranychidae) colonies and its behavior to odors of mites, avocado shoots volatiles and synthetic compounds

“…Our results yielded a rm = 0.19 females female -1 d -1 , when they preyed on all stages of O. yothersi. This rm value is lower than rm = 0.24 of red mite O. yothersi (Rioja et al, 2019). However, G. occidentalis is an efficient consumer of eggs and active stages of T. pacificus (Bruce-Oliver and Hoy, 1990;Hoy, 2011), being effective in the control of Oligonychus perseae Turttle, Baker and Abbatiello (Acari: Tetranychidae) (McMurtry et al, 2013).…”

“…In Chile, Oligonychus yothersi (McGregor) (Acari: Tetranychidae) is the most severe foliar pest of avocado 'Hass' orchards. The O. yothersi outbreaks occur between mid-summer and late autumn at Valparaíso Region (Rioja et al, 2019). Beetles Oligota pygmaea Solier (Coleoptera: Staphylinidae) and Parastethorus histrio Chazeau (Coleoptera: Coccinellidae) are observed preying all stages of O. yothersi on damaged and infested avocado trees (Hoy, 2011;Rioja et al, 2016).…”

Efficiency of entomopathogenic bacteria and fungi on Oligonychus yothersi in vitro and on Persea americana Mill. plants

“…The pest O. yothersi has been reported as a polyphagous and severe species in several countries of the world (Pinto et al, 2012;Ceballos et al, 2022), plant damage is expressed in the reduction of photosynthetic activity, the consequence of which is excessive defoliation of the plant when attacks are severe (Rioja et al, 2018;Rioja et al, 2019). Among the most susceptible varieties of Persea americana are Hass and Fuerte, with a direct consequence on fruit quality and yield (Ceballos et al, 2022).…”

“…Among the most susceptible varieties of Persea americana are Hass and Fuerte, with a direct consequence on fruit quality and yield (Ceballos et al, 2022). This is the foliar pest with the highest incidence during the autumn and summer season (Yang et al, 2015;Bayu et al, 2017;Rioja et al, 2019) whose symptoms are tanning and leaf fall, because the mite pierces the leaf with its chelicerae in the form of a stylet and sucks the cellular contents (Rioja et al, 2018;Chiaradia et al, 2021).…”