Functional Responses ofNephus arcuatusKapur (Coleoptera: Coccinellidae), the Most Important Predator of Spherical MealybugNipaecoccus viridis(Newstead)

Abstract

Nephus arcuatusKapur is an important predator ofNipaecoccus viridis(Newstead), in citrus orchards of southwestern Iran. This study examined the feeding efficiency of all stages ofN. arcuatusat different densities ofN. viridiseggs by estimating their functional responses. First and 2nd instar larvae as well as adult males exhibited a type II functional response. Attack rate and handling time were estimated to be 0.2749 h−1and 5.4252 h, respectively, for 1st instars, 0.5142 h−1and 1.1995 h for 2nd instars, and 0.4726 h−1and 0.7765 h for adult males. In contrast, 3rd and 4th instar larvae and adult females ofN. arcuatusexhibited a type III functional response. Constantband handling time were estimated to be 0.0142 and 0.4064 h for 3rd instars, respectively, 0.00660 and 0.1492 h for 4th instars, and 0.00859 and 0.2850 h for adult females. The functional response of these six developmental stages differed in handling time. Based on maximum predation rate, 4th instar larvae were the most predatory (160.9 eggs/d) followed by adult females (84.2 eggs/d). These findings suggest thatN. arcuatusis a promising biocontrol agent ofN. viridiseggs especially for 4th instar larvae and adult females.

Temperature-Dependent Functional Response of Harmonia axyridis (Coleoptera: Coccinellidae) on the Eggs of Spodoptera litura (Lepidoptera: Noctuidae) in Laboratory

“…Handling time for fourth instar (0.174 ± 0.003 h) was shorter than adult female (0.189 ± 0.004 h) and male (0.243 ± 0.05 h). Better efficacy by fourth instar and adult predators over earlier instars, as found in our study, has been supported by findings of many earlier studies where a coccinellid, Nephus arcuatus K. (Coleoptera: Coccinellidae) was fed on spherical mealybug, Nipaecoccus viridis N. (Hemiptera: Pseudococcidae) [ 83 ], and also when H. axyridis was fed on aphid, M. persicae [ 80 ] and when H. variegata was fed on Aphis fabae S. [ 40 ]. Seko and Miura [ 80 ] reported lower handling time for female (0.127 h) followed by the male (0.146 h) and fourth instar (0.156 h) H. axyridis , whereas Farhadi, Allahyari and Juliano [ 40 ] reported lower handling time for female (0.409 ± 0.048 h) followed by fourth instar (0.454 ± 0.028 h) and male (1.194 ± 0.069 h) H. variegate.…”

Multiple factors, including arena size, shape the functional responses of ladybird beetles

“…'s () compilation suggests a peak in space clearance rate for some species in the high 20s, and other parameters such as intrinsic rate of population increase also peak around 30°C for ladybird beetles (Hodek, Emden, & Honek, ). However, the maximum temperature considered here was just 30°C (Işikber, ; Zarghami, Mossadegh, Kocheili, Allahyari, & Rasekh, ), which could have led to an apparent linear response to temperature in our dataset. A unimodal response to temperature may become apparent when data are collected at temperatures that approach the extremes experienced by wild ladybird beetles (up to 40°C or so).…”

Using a Two-Sex Life Table Tool to Calculate the Fitness of Orius strigicollis as a Predator of Pectinophora gossypiella

“…It is essential to evaluate the biocontrol potential of predators, e.g., Orius spp., in the laboratory by conducting biological studies. Moreover, these studies can justify the efficiency of predator against target species before using predators in the field against insect pests [38,39], and helpful in the regulation of prey population [12,40].…”