Search Results (3)

Plant-phyllosphere feedback (PPF) is an ecological process in which phyllosphere microbiota, originating from plant litter, are transmitted via aerosols and subsequently influence the growth of conspecific or heterospecific plants. However, the cross-species generality of this mechanism and its role in invasive plant success remain to be fully elucidated. This study systematically examined PPF effects using three invasive/native congeneric plant pairs from distinct families (Phytolaccaceae, Asteraceae, and Amaranthaceae) in Jiangxi Province, China. Key findings include the following: (1) Wide conspecific negative feedback across families, with four of six species exhibiting 6.2–12.7% biomass reduction under their own litter treatments (p < 0.05). (2) Comparable feedback intensity between invasive and native species, as indicated by average pairwise indices (invasive I = −0.05 vs. native I = −0.04; p = 0.15). Notably, the invasive species Phytolacca americana uniquely showed a positive biomass response (+7.1%), though underlying mechanisms (phytochemical or microbial) were not investigated. (3) Lack of correlation between PPF strength and plant functional traits or phylogenetic distance, as indicated by Mantel tests (p > 0.8), in contrast to the trait/phylogeny associations commonly observed in soil feedback systems. This study provided the first evidence of PPF universality across multiple plant families—previously documented only within Asteraceae—and highlights the potential microbial-mediated advantages in plant invasions. Future research should integrate spatiotemporal metagenomic and metabolomic approaches to decipher the dynamic pathogen/microbe networks and their phytochemical interactions. Full article

Plant communities may be co-invaded by invasive plants, sometimes even by congeneric invasive plants (CIPs). Despite the growing understanding of co-invasion in the environment, little is known about how CIP interactions and mechanisms regulate co-invasion. Darwin’s naturalisation conundrum predicts that the coexistence of closely related species is difficult due to their structural and behavioural similarities. Nevertheless, communities containing closely related species are more susceptible to being invaded because close relatives may favour similar environments; therefore, this hypothesis should be followed in the co-invasion of CIPs. To explore whether the phylogenetic relatedness and origins of invasive species to CIPs can promote or hinder co-invasion, we conducted a controlled interaction and soil-legacy greenhouse experiment to quantify the growth response of invasive plants and their congeners. We consistently found that CIPs of identical origin were more likely to co-invade compared to CIPs of distinct origins. CIPs of distinct origins exhibited an antagonistic effect on co-invasion by allelopathy. Invasive plant-conditioned soil was more conducive to the growth of CIPs of identical origin than CIPs of distinct origins. Our results revealed the different effects of invader–invader phylogenetic relatedness on co-invader success and impact, suggesting the operation of different mechanisms across co-invasion. Full article

The Asian longhorned beetle (ALB), Anoplophora glabripennis (Motschulsky) and citrus longhorned beetle (CLB), Anoplophora chinensis (Förster) (both Coleoptera: Cerambycidae: Lamiinae), are high-risk invasive pests that attack various healthy hardwood trees. These two species share some similar host plants and overlapping distributions in large parts of their native ranges in China and the Korean peninsula as well as similar reproductive behaviors. The original Anoplophora malasiaca (Thomson) occurs in Japan and has been synonymized as CLB (hereafter referred to JCLB). In this study, a 30-min behavioral observation of paired adults, followed by a four-week exposure to host bolts, showed that ALB could not successfully cross with CLB. Mating was observed between female CLB and male ALB but not between female ALB and male CLB, no laid eggs hatched. JCLB males successfully crossed with ALB females to produce viable eggs although the overall percentage of hatched eggs was lower than those from conspecific mating pairs. However, ALB males could not successfully cross with JCLB females. CLB and JCLB mated and produced viable hybrid offspring and the hybrid F1 offspring eggs were fertile. These results suggest an asymmetrical hybridization between ALB and JCLB, and that both CLB and JCLB might be considered as two subspecies with different hybridization potential with congeneric ALB. Given their potential impacts on ecosystems and many economically important tree hosts, invasion of these geographically isolated species (ALB and JCLB) or distant subspecies (CLB and JCLB) into the same region may facilitate potential hybridization, which could be a potential concern for the management of these two globally important invasive forest pests. Further studies are needed to determine if fertile hybrid offspring are capable of breeding continually or backcrossing with parental offspring successfully. Full article