Infestation mechanisms of two woodborer species in the mangrove Sonneratia alba J. Smith in Kenya and co-occurring endophytic fungi

Abstract

Insect damage on trees can severely affect the quality of timber, reduce the fecundity of the host and render it susceptible to fungal infestation and disease. Such pathology weakens or eventually kills the host. Infestation by two insect woodborer species (a moth and a beetle) is causing mortality of Sonneratia alba, a wide-ranging pioneer mangrove species of the Indo-Pacific. Establishing the infestation mechanism of the two insect woodborer species is an initial and essential step towards understanding their ecological role in the mangroves and in determining sustainable management priorities and options. Our main objectives were to investigate the infestation mechanism employed by the two insect woodborers which infest S. alba trees, to establish the occurrence of secondary infestation by endophytic fungi in the infested S. alba branches, and to explore a control management option to the woodborer infestation. We conducted an external inspection of infested branches in two large embayments in Kenya, Gazi Bay and Mida Creek, and by splitting infested branches we determined the respective internal infestation mechanisms. Infested wood samples from Gazi Bay and Mida Creek were incubated at 28±1°C for 3–5 days to establish the presence of fungi. A survey was conducted in both Gazi Bay and Mida Creek to ascertain the presence of ants on S. alba. The infestation characteristics of the two insect woodborer species were different. It took 6–8 months for the beetle to kill a branch of 150 cm—200 cm long. For the moth to kill a branch, it depended upon several factors including the contribution by multiple species, other than the moth infestation alone. A total of 15 endophytic fungal species were identified. Two ant species Oecophylla longipoda and a Pheidole sp. inhabited 62% and 69% respectively of sampled S. alba trees in Gazi Bay whereas only Pheidole sp. inhabited 17% of the sampled S. alba trees in Mida Creek. In summary, we have documented the time it takes each woodborer species to kill a branch, the infestation mechanism of the two insect woodborers, and we hypothesized on the role of two ant species. The presence of several different fungal species was ascertained, and we discussed their possible role in the infested wood. Our results cannot unambiguously associate the woodborers and identified fungi. We recommend further studies to investigate the presence or absence, and if present, the nature of fungi in the gut of the woodborers.

Antifungal Effects of Senescence Terminalia Cattappa Leaves Extract on Disease Pathogens Associated With the Infestation of Hypsipyla robusta on Khaya grandifoliola

“…Insect pest infestation on trees induces stresses that metamorphose to poor tree growth or the eventual death of the attacked tree species (Jenoh et al, 2019). The ndings of this study agree with this assertion as the inoculated Khaya grandifoliala seedlings exhibit stunted growth compared to the control and that eventually led to their death.…”

Bioprospecting of Selected Mangrove Fruits Based-Nutritional, Antioxidant, and Element Properties to Support Functional Food Materials for Pulau Sembilan Coastal Communities, Indonesia

“…Furthermore, S. alba is the only preferred ruminant, and phenolic compounds on Kandelia candel associated with the antioxidant activity contain a large number of procyanidins and a small amount of prodelphinidins, and the epicatechin. [28]. These results provided the potential of mangrove fruits in Pulau Sembilan.…”

Diversity and Seasonal Dynamics of Airborne Fungi in Nerja Cave, Spain

“…It is of interest to notice that many of the fungi isolated were reported as entomopathogens and/or associated with arthropods, including A. versicolor, A. ustus, A. ochraceus, A. olsonii, A. welwitschiae, A. tubingensis, B. cinerea, C. cladosporioides, C. sphaerospermum, Pa. album, P. flavigenum, P. chrysogenum, P. raistrickii, P. brevicompactum, P. steckii, Pu. lilacinum, and S. brevicaulis, among others [90][91][92][93].…”