Corymbia Species and Hybrids: Chemical and Physical Foliar Attributes and Implications for Herbivory

Abstract

Hybridization is an important biological phenomenon that can be used to understand the evolutionary process of speciation of plants and their associated pests and diseases. Interactions between hybrid plants and the herbivores of the parental taxa may be used to elucidate the various cues being used by the pests for host location or other processes. The chemical composition of plants, and their physical foliar attributes, including leaf thickness, trichome density, moisture content and specific leaf weight were compared between allopatric pure and commercial hybrid species of Corymbia, an important subtropical hardwood taxon. The leaf-eating beetle Paropsis atomaria, to which the pure taxa represented host (C. citriodora subsp. variegata) and non-host (C. torelliana) plants, was used to examine patterns of herbivory in relation to these traits. Hybrid physical foliar traits, chemical profiles, and field and laboratory beetle feeding preference, while showing some variability, were generally intermediate to those exhibited by parent taxa, thus suggesting an additive inheritance pattern. The hybrid susceptibility hypothesis was not supported by our field or laboratory studies, and there was no strong relationship between adult preference and larval performance. The most-preferred adult host was the sympatric taxon, although this species supported the lowest larval survival, while the hybrid produced significantly smaller pupae than the pure species. The results are discussed in relation to plant chemistry and physical characteristics. The findings suggest a chemical basis for host selection behavior and indicate that it may be possible to select for resistance to this insect pest in these commercially important hardwood trees.

Increased attractiveness of honeybee hive product volatiles to adult small hive beetle, Aethina tumida, resulting from small hive beetle larval infestation

“…The software used for this multivariate analysis was Primer 5 for Windows (v. 5.2.9; Clarke & Gorley, 2001). These analytical procedures have been used successfully in previous studies to statistically analyse chromatographic data (Hayes et al, 2006(Hayes et al, , 2013Burgener et al, 2009;Nahrung et al, 2009).…”

Transgressive segregation of primary and secondary metabolites in F2 hybrids between Jacobaea aquatica and J. vulgaris

“…Interspecific hybrids can often be clearly distinguished from parental species based on their biochemical phenotypes. For example, natural Jacobaea hybrids can be identified based on unique profiles of pyrrolizidine alkaloids (Kirk et al 2004), interspecific eucalypt hybrids can be distinguished from parents based on intermediacy in concentrations of foliar metabolites (Nahrung et al 2009), and interspecific Solanum hybrids can be distinguished from parents based on the presence of two novel glycoalkaloids (Savarese et al 2009). …”

Behavioural responses of the small hive beetle to volatile components of fermenting honeybee hive products

“…We used a 'similarity percentages' (SIMPER) analysis to ascertain the relative contribution of each of the components to assign the fermenting products to a priori determined groups, to determine differences among groups and to assess similarity among individuals within each group. This type of analysis has been used previously to analyse chromatographic data (Hayes et al, 2006;Nahrung et al, 2009). The software used for the multivariate analysis was PRIMER 7 for Windows (v.7.0.13, PRIMERe; Clarke & Gorley, 2015).…”