Architectural diversity and galling insects on Caryocar brasiliense trees

Abstract

Galling insects are a highly sophisticated herbivore group on Caryocar brasiliense, a tree that represents the main income source for many communities. The effect of architectural diversity of C. brasiliense trees on galling insect community diversity and abundance was studied. The abundance of adult insects and galled leaves were seven and 1.6 times higher in trees with a greater height/width of canopy (RHW) ratio, respectively. Gall parasitoid richness was 1.8 times greater on trees with higher RHW. Zelus armillatus (Lepeletier & Serville) (Hemiptera: Reduviidae) and ant numbers were 5.8 and 2.7 higher on trees with the largest and smallest RHW, respectively. More complex plant architectures favored species diversity for galling insects and their natural enemies. The competition among four galling insect species for space and feeding and the evidence of “prudence strategy” were, for the first time, observed for galling insects in the Brazilian Cerrado biome.

Diversity of arthropods on Acacia mangium (Fabaceae) and production of this plant with dehydrated sewage sludge in degraded area

“…This confirms the second hypothesis that the diversity and abundance of herbivorous insects and their predators are usually higher and with higher increase of chewing insects than predators (e.g. >leaves ≤predator per prey ratio) on trees with higher leaf mass [25,53,54]. These trees function as a BGI, but with a higher chance of rare species extinction on those with lower leaf mass [25,28,55].…”

Does fertilization with dehydrated sewage sludge affect Terminalia argentea (Combretaceae) and associated arthropods community in a degraded area?

“…Such an observation confirms the first hypothesis (i.e. ETIB), that the diversity and abundance of phytophagous insects, pollinators and their predators are usually higher on larger trees with higher leaf mass 5 , 15 – 17 . Thus, trees such as T. argentea , may seem as islands (as proposed by ETIB), and those with lower leaf mass present a higher chance to get extinct the endangered species 5 , 17 , 22 , 23 .…”

“…The aims here were to assess for 24 months the ecological indices (abundance, diversity and species richness) and ecological processes (herbivory and predation) of phytophagous, pollinators and predators arthropods on T. argentea trees, fertilized (or not) with DSS in a degraded area. We hypothesize that (i) T. argentea trees resemble living islands, and that the fertilization with DSS may increase the canopy size (canopy islands), and thus accommodate larger numbers of phytophagous, pollinators and predators arthropods (> the equilibrium theory of island biogeography—ETIB) 5 , 15 – 17 ; (ii) there is competition between groups of phytophagous insects, such as hemipterans, coleopterans and orthopterans 18 , 19 ; and (iii) arthropod predators, such as insects and spiders, reduce the number of phytophagous insects and thus herbivory on T. argentea trees 19 – 21 .…”

Accumulation of Urban Insect Pests in China: 50 Years’ Observations on Camphor Tree (Cinnamomum camphora)

“…Especially in 1964, pests on C. camphora were first detected in Jiangxi, and extreme weather phenomena represented by drought and heavy rain occurred sequentially before the pest outbreak [50]. Similarly, there was pest detection in urban areas in Montes Claros, Brazil, with the tropical savanna climate [51]. In addition, the increased pest damage was also observed on heavily watered trees in urban areas [21].…”