Host plant affects morphometric variation of Diaphorina citri (Hemiptera: Liviidae)

Abstract

The Asian citrus psyllid (ACP), Diaphorina citri Kuwayama, is one of the most serious citrus pests worldwide due to its role as vector of huanglongbing or citrus greening disease.While some optimal plant species for ACP oviposition and development have been identified, little is known of the influence of host plants on ACP size and shape. Our goal was to determine how size and shape of ACP wing and body size varies when development occurs on different host plants in a controlled rearing environment. ACP were reared on six different rutaceous species; Bergera koenigii, Citrus aurantifolia, Citrus macrophylla, Citrus maxima, Citrus taiwanica and Murraya paniculata. Adults were examined for morphometric variation using traditional and geometric analysis based on 12 traits or landmarks. ACP reared on C. taiwanica were consistently smaller than those reared on the other plant species. Wing aspect ratio also differed between C. maxima and C. taiwanica. Significant differences in shape were detected with those reared on M. paniculata having narrower wings than those reared on C. macrophylla. This study provides evidence of wing size and shape differences of ACP based on host plant species which potentially may impact dispersal. Further study is needed to determine if behavioral and physiological differences are associated with the observed phenotypic differences. 63Morphometric analysis provides a tool to evaluate phenotypic variation that results from 64 a range of biotic and abiotic factors (Daly, 1985). Traditional morphometric analysis of size and 65 size ratios has been the classical approach for quantifying variation in biological specimens. It is 66 used to determine instar, and to compare genetic, environmental and phenotypic variation (Daly, 67 1985). A newer approach, geometric morphometric analysis, provides a mechanism to evaluate 68 shape independent of size through the use of landmarks on two-and three-dimensional surfaces , 1990; Bookstein, 1991 Bookstein, , 1996 Rohlf & Marcus, 1993;Dryden & Mardia, 1998).70 Geometric morphometric analysis has provided insight into patterns of morphological variation 71 associated with Musca domestica L. wild populations and laboratory colonies (Ludoški et al.,72 2014), wild sandfly populations (Santos et al., 2015), the discrimination of four species of Culex 73 mosquitoes (Laurito et al., 2015) and synonymy of two Bactrocera species (Schutze et al., 2015).74 Geometric morphometric analysis has also been instrumental in visualizing and comparing

Size and shape analysis of Trioza erytreae Del Guercio (Hemiptera: Triozidae), vector of citrus huanglongbing disease

“…These significant morphometric differences potentially could play a significant role in fecundity, dispersal, and fitness . Both methods have been previously used to group ACP, the Asian counterpart from field populations and populations raised on different host plants under laboratory conditions …”

“…Data analyses for traditional and geometric morphometrics were conducted similarly to previous morphometric studies on ACP . Traditional linear morphometric measurements of male and female psyllids were compared using Welch's t ‐test or the Student t ‐test.…”

“…The use of morphometric analyses as tools to evaluate phenotypic variations that result from both biotic and abiotic factors as well as differences associated with development and genetic factors have been demonstrated by several authors . These differences may be related to and can provide insight into the effects of host plants on factors affecting attributes such as survival and fecundity …”

“…These differences may be related to and can provide insight into the effects of host plants on factors affecting attributes such as survival and fecundity and Paris et al ., traditional morphometrics analysis of size and size ratios is the classical approach for quantifying variation in biological specimens and is used to determine instar, and to compare genetic, environmental, and phenotypic variations . Other reliable approaches used include geometric morphometrics analysis, which focuses on mechanisms that provide an in‐depth evaluation of shape independent of size through the use of landmarks on two‐ and‐three‐dimensional surfaces .…”

“…Other reliable approaches used include geometric morphometrics analysis, which focuses on mechanisms that provide an in‐depth evaluation of shape independent of size through the use of landmarks on two‐ and‐three‐dimensional surfaces . It can be used to remove the confounding effects of size, rotation, and orientation and is sensitive enough to detect subtle differences characteristic of subpopulations within a single species . For example, it has been used to elucidate patterns of morphological variation associated with wild populations and laboratory colonies of the common housefly Musca domestica L. (Diptera: Muscidae), wild sandfly populations, the discrimination of four species of Culex mosquitoes (Diptera: Culicidae) and synonyms of two Bactrocera species (Diptera: Tephritidae) …”